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T HE A STRONOMICAL J OURNAL ,121:1163È1170,2001February(2001.The American Astronomical Society.All rights reserved.Printed in U.S.A.HUBBL E SPACE T EL ESCOPE NICMOS SPECTROSCOPY OF CHARONÏS LEADINGAND TRAILING HEMISPHERESC HRISTOPHED UMAS AND R ICHARD J.T ERRILEJet Propulsion Laboratory,Mail Stop 183-501,California Institute of Technology,4800Oak Grove Drive,Pasadena,CA 91109R OBERT H.B ROWNLunar and Planetary Laboratory,University of Arizona,1629East University Boulevard,Tucson,AZ 85721G LENN S CHNEIDERSteward Observatory,University of Arizona,933North Cherry Avenue,Tucson,AZ 85721ANDB RADFORD A.S MITHInstitute for Astronomy,University of Hawaii,2680Woodlawn Drive,Honolulu,HI 96822Received 2000August 1;accepted 2000November 6ABSTRACTWe used the near-infrared camera and multiobject spectrometer NICMOS on the Hubble Space Telescope to obtain 1.1È2.4k m,low-resolution (R D 200)slitless grism spectrophotometry of the individ-ual members of the Pluto-Charon system.Water ice is present in its crystalline state on both the leading and trailing hemispheres of Charon.A 2.21k m absorption band,possibly due to the presence of ammonia hydrate in surface,is detected in the reÑectance spectrum of its leading side only.Geological activity on Charon or implantation of ions escaped from PlutoÏs atmosphere could account for the for-mation of species such as locally on the satellite.We also measured a slightly higher geomet-NH 3ÉH 2O ric albedo for Charon than reportedfrom the mid-1980s observations of the mutual events.Key words:planets and satellites:individual (Charon)Ètechniques:spectroscopic1.INTRODUCTIONAlthough PlutoÏs discovery was made 70years ago,most of the information we have collected on its surface composi-tion has been obtained only very recently.Sensitive tele-scope instrumentation is now available to carry out spectrophotometric observations of the Pluto-Charon system at visible and,particularly,at near-infrared wave-lengths,a spectral range that provides an excellent diagnos-tic of the physical state of the ices present on the surface.The surface of Pluto was Ðrst suggested to be primarily covered with methane ice (Cruikshank,Pilcher,&Morrison 1976).Additional photometric observations,carried out at various rotational phases (Buie &Fink 1987),showed that methane is not distributed uniformly over the surface.Owen et al.(1993)reported that ice is in fact the mostN 2abundant compound on Pluto,followed by and CO.CH 4Currently,the planet is moving away from the Sunand itsatmosphere is slowly condensing on the surface (Stern,Trafton,&Gladstone 1988).While gas should also beN 2the main constituent of PlutoÏs atmosphere (Owen et al.1993),only methane gas has already been detected,from the band at 1.67k m (Young et al.1997),and CO gas awaits 2l 3detection.PlutoÏs surface displays patches of bright N 2-richregions and dark nitrogen-depleted areas (Jewitt 1994).N2ice may be concentrated in the polar regions at tem-peratures ¹40K (Tryka et al.1994),while ices with lower volatility should cover the equatorial regions.The surface temperature varies locally,and recent Infrared Space Obser -vatory measurements (Lellouch et al.2000)conÐrmed the presence of cold-bright regions and warm-dark regions.The visible albedo distribution across Pluto was determined from light-curve inversion techniques (Buie,Tholen,&Horne 1992;Young et al.1999)and direct imaging using the Hubble Space Telescope (HST )Faint Object Camera (Stern,Buie,&Trafton 1997).Both methods conÐrmed the presence of bright polar regions,while the equatorial zone displays a darker but highly variegated surface.Because of the small angular separation between Pluto and its satellite (from to our knowledge of 0A .30A .9),CharonÏs surface composition could,until recently,only be deduced from the analysis of the mid-1980s occultation events.These observations showed that Charon is mostly covered with ice (Buie et al.1987;Marcialis,Rieke,&H 2O Lebofsky 1987;Fink &DiSanti 1988).Later analysis by Roush (1994)and Roush et al.(1996)of the mid-1980s photometric measurements suggested that the surface of Charon could also be covered with patches of iceCO 2mixed with large-grained ice in addition to CH 4H2O.Dumas et al.(1999)reported HST Near Infrared Camera and Multi-Object Spectrometer (NICMOS)observations revealing for the Ðrst time the crystalline state of water ice over Charon.This result was conÐrmed by independent NICMOS observations of Charon made by Buie &Grundy (2000),as well as by ground-based observations carried out at Keck Observatory by Brown &Calvin (2000).Brown &Calvin also reported the presence of a 2.21k m band in their spectrum of Charon,which they attributed to the presence of ammonia ice on the surface.This paper presents the results of a reanalysis of the HST NICMOS observations obtained by Dumas et al.(1999).We conÐrm the presence of a 2.21k m absorption feature in the spectrum of Charon;however,this absorption appears to be detected only in the spectrum of the leading hemi-sphere.This result suggests that resurfacing processes,pos-11631164DUMAS ET AL.Vol.121TABLE1G EOMETRY OF THE P LUTO-C HARON S YSTEM DURING THE1998J UNE““C AMERA3C AMPAIGNÏÏProperty Jun11,UT1301a Jun14,UT1456aHeliocentric distance(AU)................30.068430.0692Geocentric distance(AU).................29.104929.1190Sub-Earth latitude(deg)...................[21.4[21.3PlutoÏs sub-Earth longitude(deg)........99.6(max.light curve)273.2(min.light curve)CharonÏs sub-Earth longitude(deg)......279.7(trailing side)93.2(leading side)Separation(arcsec).........................0.9080.917CharonÏs position angle(deg)............169.95347.65Spectral separation(pixels)............... 2.55(\0A.517) 2.70(\0A.548)a Time at beginning of G206series.sibly involving Pluto,are currently occurring on Charon.A mechanism is discussed that involves bombardment of CharonÏs surface by ions escaping from PlutoÏs atmosphere.2.OBSERVATIONSWe report spectroscopic observations of the Pluto-Charon system obtained in1998on June11and14(HST program GTO7223)at CharonÏs maximum elongation using HST and its near-infrared camera and multiobject spectrometer NICMOS(Thompson et al.1998).The details of the geometry of the Pluto-Charon system are described in Table1.Planetocentric coordinates were calculated for both dates using the1994IAU model(Davies et al.1995). NICMOS has three256]256HgCdTe low-noise detec-tors covering a0.8È2.4k m spectral range with pixel scales ranging from43mas pixel~1(camera1)to203mas pixel~1 (camera3).Camera3(NIC3)is equipped with a set of three grisms,an optical setup combining a prism and a grating, providing low-resolution(R D200)slitless spectro-photometric capabilities.In this paper,we discuss the results obtained using NIC3and the G141and G206 grisms,spanning a spectral range from 1.1to 2.4k m. Though NIC3normally produces slightly afocal images, our data were obtained during the1998June““camera3 campaign,ÏÏduring which HSTÏs secondary mirror was adjusted to achieve optimal optical performance.Pluto and Charon were separated by for the dates of our obser-0A.9vations.However,because of HST scheduling constraints, the line joining the binary system could not be oriented perpendicular to the dispersion direction;hence,the spatial separation of the spectra was reduced to(Table1).0A.5Table2summarizes the exposure parameters for the G141 and G206grisms.Because the wavelength solution of each spectrum is a function of the position of the science target on the detector,we initially obtained an image of Pluto-Charon through the F150W broadÐlter.Two spectra of Pluto-Charon(320s per exposure)were then recorded with the G141grism.A small telescope o†set was implemented between each exposure to collect data from di†erent loca-tions on the detector and to reduce the contamination ofTABLE2G RISM O BSERVATION P ARAMETERSParameter G141G206Spectral coverage(k m)...... 1.1È1.9 1.4È2.5Number of exposures (212)Total exposure time(s)......639.9767.4NICMOS sequence..........STEP64STEP16our data fromÑat-Ðeld residual e†ects,as well as to sample around bad pixels.The last step was to acquire the long-wavelength spectra using the G206grism.Because the G206 background level was D150times higher than for the G141 grism,shorter exposures were required in order to avoid saturation.We recorded a series of12spectra(64s each)at four di†erent locations on the detector(three images per position of the telescope).3.DATA REDUCTIONThe extraction and absolute photometric calibration of the spectra of Pluto and Charon were achieved using the ““NICMOSlookÏÏsoftware(Pirzkal&Freudling1998; McCarthy et al.1999),developed at the Space Telescope European Coordinating Facility for reduction of the NICMOS spectroscopic data.3.1.Separation of Pluto and CharonTheÐrst step in data reduction was to subtract the back-ground from the G206images.The background was esti-mated from a median combination of the set of four-position dithered G206images.The low background level for the G141grism was simplyÐtted during the extrac-tion.Because the spectra of the two objects partially overlap,we estimated their individual contributions and created,for each original spectrum,two images containing separate synthetic spectra of Pluto and Charon.Figure1 shows the result ofÐtting the contribution of Pluto and Charon along one detector column.Because the pixel~10A.2scale of NIC3oversamples the point-spread function(PSF), each image wasÐrst rebinned to aÐner grid(rebin factor\8)via bicubic convolution interpolation(Park& Schowengerdt1983).The angle of dispersion of the spectra with respect to the detectorÏs horizontal axis was measured, as well as the location where the spectrum was illuminating the exact center of one pixel.From the knowledge of these two parameters,we could estimate the width of PlutoÏs and CharonÏs PSFs.The separated synthetic spectra of Pluto and Charon were obtained by adjusting the amplitude and position of the two PSFs in order to minimize the variance of the di†erence between the original and the synthetic pro-Ðles(Fig.1).This measurement was made over the range of pixels covered by the two objects,and a goodÐt was reached after only three iterations.The process returned two images corresponding to the separated spectra of Charon and Pluto,which were rebinned back to the orig-inal resolution.The maximum count rate for Pluto in a single G206exposure was near330e~s~1,while the residual count rate was in the^13e~s~1range(NIC3 gain\6.5e~ADU~1).The residual image(original imageNo.2,2001NEAR-IR SPECTROSCOPY OF CHARON 1165F IG .1.ÈCross section of a rebinned G206spectrum of Pluto-Charon along the spatial direction (y -axis of the detector).The original proÐle is noted with diamonds,while the synthetic proÐle of Pluto plus Charon is indicated by the red line.The residual of the Ðt (original proÐle minus synthetic)is represented with a black line.For each original image,two synthetic images are produced by Ðtting the individual contributions of Pluto and Charon along the detector columns (three iterations of the Ðtting algorithm).The synthetic images are then used to extract the indi-vidual spectra of Pluto and Charon.minus synthetic)was used to improve the models of PlutoÏs and CharonÏs spectra.The total Ñux in a detector pixelF T due to Pluto and Charon is simply (F P )(F C )F T \F P ]F C,and the residual value for one particular pixel is res \F origwhere is the Ñux of the original image for this[F T ,F orig pixel.Then the corrected Ñuxes for the Ðts of Pluto and Charon are respectively and F P @\F P ](F P /F T )res F C@\This correction,performed individually F C ](F C /F T )res.forall pixels,allows us to conserve the original total Ñux of Pluto and Charon while correcting the models for the uncertainties in the individual pixel response and the exact position of the PSF with respect to the center of the pixel.3.2.Extraction of the SpectraAt this stage,the data have been processed in such a way that we can extract and photometrically calibrate the G141and G206spectra of Pluto and Charon.Version 2.9.2of NICMOSlook (Freudling &Pirzkal 1998;Pirzkal &Freudling 1998)was used for this purpose.The wavelength solution for all NICMOS grisms as a function of the posi-tion of the object on the detector has been parameterized.The only adjustment we made consisted of accounting for the planetÏs apparent motion,which had the e†ect of modifying the original position measured from the F150W image.The NICMOS detectors do not have spatially Ñat responses across their pixels.Thus,the Ñux measured in an undersampled pixel depends upon the location of the PSF core with respect to the pixel center.It was therefore neces-sary to extract the spectra using a model of the intrapixel response function (IPRF;see Lauer 1999for a detailed description).The average e†ect of the IPRF was larger for ““camera 3campaign ÏÏobservations than for observations carried out when the PSF was not exactly in focus for NIC3.Similarly,because the PSF is better sampled at longer wavelengths,the correction for the G206grism data was smaller than for the G141grism.We used the obser-vations of the solar analog P330-E collected during the 1998June ““camera 3campaign ÏÏ(HST program 7959)to determine the amplitude of a characteristic IPRF correction to apply to our G206and G141spectra.The scatter of the data points was measured before and after applying the IPRF correction.For this purpose,we deÐned the mean spectrum for each grism and subtracted it from the individ-ual spectra to calculate the means of the standard devi-ations over a deÐned range of wavelengths.After applying the IPRF,we measured a decrease in the means of the standard deviations of 10%and 40%,respectively,for the G206and G141grisms.3.3.Calibration3.3.1.Spectral CalibrationGiven that the wavelength solution for each spectrum is a function of the target location on the detector,the estima-tion of this location (from the F150W image and the appar-ent motion of the object)provides an additional source of error for the spectral calibration.The wavelength sampling of the spectra after extraction is 10nm pixel ~1(G206grism).Therefore we Ðrst rebinned the individual spectra to a Ðner grid prior to co-registering them (this process was similarly applied to the spectrum of the solar analog P330-E).The spectra of P330-E and Pluto-Charon were then co-registered,using the absorption bands visible in both spectra as Ðducial.Because of the lower signal-to-noise ratio (S/N)of the G206data,and the deep bands of methane and water present at these wavelengths,the co-registration process returned a less accurate wavelength calibration for the G206grism than for G141.The accuracy of the wavelength calibration of the spectra is of the order of 20nm for the G206grism,slightly better at shorter wave-lengths (G141grism).This is illustrated by the small shifts (¹20nm)in wavelength that can be measured for the 1.85k m band of methane and the 2.05k m band of water in Figure 2.Smaller wavelength shifts can also be noticed for the G141grism.Such shifts result from the uncertainty in the wavelength calibration of our data set and do not rep-resent any real hemispheric variations in the physical state of the surface ices.3.3.2.Radiometric CalibrationFor each pixel,the response function in wavelength used to Ñat-Ðeld the spectra was determined by interpolating the narrowband Ñat Ðelds (*j /j D 1%)obtained as part of the standard NICMOS Cycle 7calibration program.The inverse sensitivity curves (used by NICMOSlook to convert the spectral Ñux into millijanskys)were obtained for each grism from observations of the calibrator stars P330-E and G191-B2B collected during the 1998June ““camera 3cam-paign.ÏÏThe intensities of the individual G206spectra were adjusted to minimize the scatter in our data set,and the 1p errors represent the residual dispersion after parison of the G141and G206spectra shows a mis-match in the overlap region,and we estimate the G206Ñux to be 12%higher than the G141Ñux after ing recent ground-based observations of Pluto carried out by Owen et al.(1993)and recalibrated in geometric albedo by Roush et al.(1996),we Ðnd that the G141grism calibration is best matched by the ground-based results,giving geometric albedos of p D 0.55and p D 0.7at 1.9k m for the minimum and maximum of PlutoÏs light curve,respectively.The precision of the Ñux calibration returned1166DUMAS ET AL.Vol.121by the G141grism is higher because its lower background makes the extraction of the photometric calibrators more accurate.We therefore selected the G141grism as the refer-ence for our photometric calibration.Our spectra of Pluto and Charon were then divided by the spectra of the solar analog P330-E (which were extracted using NICMOSlook as described above).After correction of our spectra for the solar spectrum,we calibrated the spectra of Pluto and Charon in geometric albedo using the solar Ñux given by Labs &Neckel (1968)and the radii for Pluto (1151^4km)and Charon (591^5km)determined by Reinsch,Burwitz,&Festou (1994).An independent reference for the solar Ñux (Thekekara 1973)was used and returned the same cali-bration values.4.RESULTS AND DISCUSSIONFigure 2shows the calibrated NICMOS spectra of Pluto and Charon obtained for the two dates 1998June 11and 14.The spectra have been slightly smoothed (convolution with a 2pixel wide Gaussian)in this Ðgure in order to make their comparison easier.The original spectra with error bars are presented below,along with the modeling results in °4.2.2.4.1.PlutoThe focus of this paper being Charon,we will not provide a detailed model and discussion for the case of Pluto (Fig.2a )and will refer to et al.(1999)for recent modeling Douteof PlutoÏs spectra.Nevertheless,we will note,as a proof of the validity of the extraction procedure described above,that (1)the two grism spectra are self-consistent in the 1.60È1.85k m overlap region and (2)there is excellent agreement between our NICMOS spectra and the higher resolutionspectra obtained by et al.(1999).The strong bands of Doutemethane ice are clearly visible,as well as the 2.15k m dip due to particularly for the spectrum that corresponds toN 2,minimumof PlutoÏs light parison of our spectra at both light-curve minimum and maximum with the higher resolution ground-based spectra obtained at UKIRT by Cruikshank et al.(1997)also shows an excellent agreement between the two data sets for the 1.9k m ““continuum ÏÏregion.At shorter wavelengths,we note that our determi-nation of PlutoÏs albedo is slightly higher than that reported by the UKIRT measurements,but comparison of the rela-tive 1.22k m/1.9k m ratio of the continuum between CH 4our calibrated NICMOS spectra and recent ground-based data obtained at Keck (Brown &Calvin 2000)conÐrms that the continuum level for the blue end of the spectra is higherF IG .2.ÈG141and G206spectra of (a )Pluto and (b )Charon obtained during the ““camera 3campaign ÏÏof 1998June.The species responsible for the absorption bands detected in our spectra are noted on the Ðgures.Near-infrared spectroscopy of Charon shows that the 1.65k m feature of crystalline water ice is visible for both the leading and trailing sides.The 2.21k m absorption reported from Keck observations of Charon by Brown &Calvin (2000)is visible in the HST NICMOS spectrum,but for the leading hemisphere only.Whatever compound is responsible for(NH 3?)this absorption,it is more abundant on the leading sideof the satellite than on its trailing side.than previously reported.Additional discussion about the Ñux calibration of our NICMOS data is presented in °4.2.2.Table 3presents the broadband photometric measurements derived from our spectroscopic data set for both obser-TABLE 3N EAR -I NFRARED P HOTOMETRY OF P LUTO -C HARON P LUTO (mag)C HARON (mag)D ATE (1998)J a H b K c J a H b K c Jun 11......12.69^0.0112.66^0.0113.09^0.0414.74^0.0314.70^0.0214.81^0.12Jun 14......12.83^0.0212.81^0.0213.19^0.0414.70^0.0414.63^0.0414.81^0.10N OTE .ÈThese measurements are derived from the spectra in Fig.3.The error bars in magnitude reÑect only the 1p uncertainty plotted in the Ðgure.The absolute photometric accuracy of the grisms in NIC3is itself evaluated to be in the 5%È10%range.a J :1.15È1.35k m;0mag \1576.2Jy for k m.j eff \1.25b H :1.50È1.80k m;0mag \1018.6Jy for k m.jeff \1.65c K :2.00È2.40k m;0mag \672.8Jy for k m.j eff\2.20No.2,2001NEAR-IR SPECTROSCOPY OF CHARON 1167vation dates.We measure a magnitude di†erence *KD 0.1between maximum and minimum of PlutoÏs light curve,which agrees with previous ground-based observations.4.2.CharonFigure 2b compares the calibrated spectra of the leading and trailing hemispheres of Charon and shows that (1)water ice appears to be in its crystalline state on both hemi-spheres,(2)the HST NICMOS geometric albedo is slightly higher than reported from analysis of the mid-1980s mutual occultation events,and (3)spectral features characteristic of species such as hydrogen cyanide (HCN)or,more probably,ammonia hydrate are present in the spectrum(NH 3ÉH 2O)of CharonÏs leading side.4.2.1.Crystalline Ice versus AmorphousThe spectra of Figure 2b show the 1.65k m spectral feature characteristic of crystalline water ice for both the trailing and leading hemispheres of the satellite.Water ice has also been found in its crystalline state on the surfaces of the large satellites of Uranus (Grundy et al.1999).This suggests that resurfacing processes can occur in the outer solar system at a faster rate than required for water ice to turn into its amorphous state under the action of solar irradiation (Strazzulla et al.1992).A possible mechanism,proposed by Brown &Calvin (2000),implicates vapor-ization of the outermost layers of water ice on Charon by micrometeorite bombardments and recondensation of this ice into its crystalline state over the surface of the satellite.Figure 2b also shows di†erences between the spectral response of CharonÏs leading and trailing hemispheres.In particular,the spectral slope at short wavelengths is stron-ger for the leading side,which could be directly linked to the nature of the neutral absorber in surface.Also,the depth of the 1.55k m water band is shallower for the leading side,which might indicate hemispheric variations in the grain size distribution of water ice,although we would expect a similar behavior for the 2.02k m water band.The 2.21k m feature in the spectrum of CharonÏs leading side will be discussed below in °4.2.3.4.2.2.Geometric Albedo of CharonTable 3presents the broadband photometric measure-ments derived from the spectra of CharonÏs trailing and leading sides.The K -band magnitude di†erence between the hemispheres is within the uncertainty of our measure-ments,conÐrming that the leading and trailing sides of Charon have a similar brightness.The calibration of our HST NICMOS spectra returns a value for CharonÏs geo-metric albedo of p D 0.42^0.05in the 1.8k m water contin-uum region (Fig.2b ),which is slightly higher than the p D 0.34^0.05measurement (Roush et al.1996)derived from the mid-1980s mutual events (although both error bars overlap).The di†erence in CharonÏs geometric albedo reported in this paper is small,but larger than the uncer-tainty of the NICMOS grism calibration.The latter is esti-mated to be a few percent higher than the 5%È10%range reported by Freudling &Pirzkal (1998),mainly because of the processes applied to our data to separate the contribu-tions of Pluto and Charon.Furthermore,the good agree-ment between the NICMOS determination of PlutoÏs geometric albedo (Fig.2a )and earlier ground-based mea-surements supports the absolute calibration of our data.This sensibly higher determination of CharonÏs albedocannot be produced by residual contamination from the planet.Indeed,the immediate consequence would be to underestimate PlutoÏs albedo,whereas our measurements agree with the ground-based results.The slightly higher NICMOS albedo is consistent (within the error bars)with the earlier results and might simply reÑect larger uncer-tainties than previously estimated in CharonÏs diameter and in the photometric calibration of the mutual-event data.Nevertheless,we cannot entirely rule out the possibility that the di†erences measured in the albedos of Pluto and Charon could result from systematic errors in the radio-metric calibration returned by the NICMOSlook package.If the increase in albedo is real,then it might suggest time-variable phenomena over Charon,such as seasonal changes occurring while the system is moving away from the Sun.Also,the satellite is now observed with an aspect angle 10¡larger than during the 1987mutual events,presenting a slightly larger apparent cross section of its southern polar region.The present geometry could contribute to an increase in albedo if the southern polar region is made of material that exhibits a high reÑectivity at these parison with other icy satellites of the outer solar system is possible.Near-infrared spectroscopy of the large satellites of Saturn returns geometric albedo measure-ments in the range p D 0.2(Hyperion)to p D 1.0(Mimas).The NICMOS observations show that CharonÏs albedo of p D 0.4at 1.8k m is very similar to the albedo of IapetusÏs trailing side,which is typical of a ““dirty ice ÏÏcomposition.Figure 3shows the result of modeling the reÑectance spectra of CharonÏs leading and trailing hemispheres with an intimate mixture (D 90%)of crystalline water ice (Grundy &Schmitt 1998)and D 10%of a spectrally blue component,the latter being required to match the contin-uum level at short wavelengths.In this model,the water ice is made of 30k m grains while the blue component corre-sponds to 10k m particles having a reÑectance spectrum decreasing linearly from 8%to 6%over the 1.0È2.7k m region.Both spectra of Charon are reasonably well matched by the spectrum of pure water ice,except for the 2.21k m band and the short-wavelength region (CharonÏs trailing side).The modeling results do not require the addi-tion of ice or ice to improve the Ðnal Ðt.CO 2CH 44.2.3.T he L eading Hemisphere of CharonThe HST NICMOS spectrum of CharonÏs leading side(Fig.3b )is identical to the spectrum of the same side of the satellite obtained at Keck by Brown &Calvin (2000).It displays the same 2.21k m spectral feature that was attrib-uted to the presence of ammonia hydrate on the surface of the satellite.This additional and independent detection of the 2.21k m band suggests that this spectral feature is real and rules out the possibility that it could be produced by residual contamination from Pluto.The Ðrst obvious candidate for this 2.21k m feature is ice itself.Although we do not expect methane ice to CH 4still be present over CharonÏs surface,we nevertheless modeled the spectrum of CharonÏs leading side (Fig.4)with an intimate mixture of water ice (D 78%;30k m grain size),methane ice (D 15%;30k m grain size),and D 7%of the spectrally blue compound described above.The model pre-sented in Figure 4shows that adding methane ice to the mixture does not provide a good match to the features observed in the spectrum of CharonÏs leading side.The small amounts of methane used in the model can reproduce。

LABORATORY PRIMATENEWSLETTERVol. 48, No. 3Ju ly 2009JUDITH E. SCHRIER, EDITORJAMES S. HARPER, GORDON J. HANKINSON AND LARRY HULSEBOS, ASSOCIATE EDITORS MORRIS L. POVAR AND JASON MACHAN, CONSULTING EDITORSELVA MATHIESEN, ASSISTANT EDITORALLAN M. SCHRIER, FOUNDING EDITOR, 1962-1987Published Quarterly by the Schrier Research LaboratoryPsychology Department, Brown UniversityProvidence, Rhode IslandISSN 0023-6861POLICY STATEMENTThe Laboratory Primate Newsletter provides a central source of information about nonhuman primates and related matters to scientists who use these animals in their research and those whose work supports such research. 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Persons who have absolutely no access to the Web, or to the electronic mailing, may ask to have paper copies sent to them.The publication lag is typically no longer than the three months between issues and can be as short as a few weeks. The deadline for inclusion of a note or article in any given issue of the Newsletter has in practice been somewhat flexible, but is technically the tenth of December, March, June, or September, depending on which issue is scheduled to appear next. Reprints will not be supplied under any circumstances, but authors may reproduce their own articles in any quantity.PREPARATION OF ARTICLES FOR THE NEWSLETTER. – Articles, notes, and announcements may be submitted by mail, e-mail, or computer disk, but a printed copy of manuscripts of any length or complexity should also be sent by regular mail.. Articles in the References section should be referred to in the text by author(s) and date of publication, e.g., Smith (1960) or (Smith & Jones, 1962). Names of journals should be spelled out completely in the References section. Latin names of primates should be indicated at least once in each note and article. In general, to avoid inconsistencies within the Newsletter, the Latin names used will be those in Mammal Species of The World: A Taxonomic and Geographic Reference, 2nd Ed. D. E. Wilson & D. M. Reeder (Eds.). Washington, DC: Smithsonian Institution Press, 1993. For an introduction to and review of primate nomenclature see The Pictorial Guide to the Living Primates, by N. Rowe, Pogonias Press, 1996.All correspondence concerning the Newsletter should be addressed to:Judith E. Schrier, Psychology Department, Box 1853, Brown UniversityProvidence, Rhode Island 02912 [401-863-2511; FAX: 401-863-1300]e-mail address: primate@Current and back issues of the Newsletter are available on the World Wide Web at/primateACKNOWLEDGMENTSThe Newsletter is supported by Brown University.Cover photograph of ring-tailed lemurs (Lemur catta),taken at the San Diego Zoo by Paul Wilde, 1997Copyright © 2009 by Brown UniversityThe Effects of Exposure to an Expanded Environmental Enrichment Program onSelect Individual Behaviors in BaboonsAmy K. Goodwin, Susan A. James, Kelly E. Lane, Michael C. McDermott, Rebecca L. Rodgerson, and Nancy A. Ator Johns Hopkins University School of Medicine, Department of Psychiatry and Behavioral Sciences, Division of BehavioralBiologyIn our laboratory, we had often discussed our desire to create an area in which our singly housed, adult male ba-boons could be released to exercise. The opportunity to do so arose when an environmental enrichment grant from the Center for Alternatives to Animal Testing at Johns Hopkins University provided funding for such a project. Thus, the goals of the present study were to cre-ate an area large enough for baboons to safely engage in species-specific behavior (i.e., free movement, explora-tory behavior, foraging) and to learn whether exposure to this environment would be correlated with changes in target behaviors considered indicators of psychological well-being.MethodsSubjects: Six adult male baboons (Papio anubis; Primate Imports, New York, NY, or Southwest Foundation for Biomedical Research, San Antonio, TX) served as sub-jects in the present study. The six baboons (BB, DC, SY, CY, DE and SC) had been in the laboratory for at least three years and had been subjects in behavioral pharma-cology studies. During the present study, the behavioral pharmacology studies in which they participated included acute exposure to psychoactive compounds. Subjects were individually housed in stainless steel primate cages equipped with a bench running along one cage wall. The home cages, which provided 10 square feet of floor space (46.5 cubic feet total space), also served as the experi-mental chambers, so the behavioral pharmacology ex-periments took place in the home cage. Such experiments typically involve the use of one or more levers, stimulus lights, tones, and food pellet delivery. The baboons had visual and auditory access to other baboons.The baboons had continuous access to tap water from a spout at the front of their cages and received a daily ration of Lab Diet (®PMI Nutrition International) or Pri-mate diet (®Harlan Teklad) biscuits, one or two pieces of Amy K. Goodwin, Johns Hopkins Univ. Sch. of Med., Behav-ioral Biology Research Center, 5510 Nathan Shock Dr., Suite 3000, Baltimore, MD 21224 [410-550-2781; fax: 410-550-2780; e-mail: Goodwin@].The establishment of the enrichment room was made possi-ble through an Animal Welfare Enhancement Award made by the Johns Hopkins University Center for Alternatives to Animal Testing. The authors would also like to thank Dan Rodgerson for the technical expertise he lent to the project, and Robert J. Adams, DVM, for helpful comments during the protocol review process and manuscript preparation.fresh fruits or vegetables daily, and children’s chewable multivitamins. Daily feeding occurred in late morning (never prior to time spent in the enrichment room). The enrichment program already established in the colony, which included human interaction, access to three or more toys (forage boxes, puzzle feeders, mirrors, Kong® toys, wood logs), and music continued without change during the present study.The overhead lights in the housing room were on for 13 h/day (6:00-19:00 h) and off for the remaining 11 h/day. Natural light also illuminated the room.Routine physical examinations (under ketamine hy-drochloride anesthesia) occurred every two weeks or ap-proximately once per month, depending on the study in which each subject was serving.All protocols were approved by the Johns Hopkins University Animal Care and Use Committee. Animal care and use and facility maintenance followed the Guide for the Care and Use of Laboratory Animals (1996) and the U. S. Animal Welfare Regulations. Johns Hopkins University is accredited by the Association for Assess-ment and Accreditation of Laboratory Animal Care Inter-national.Room Construction: It was vital that the time and effort required to create the enrichment room space be manage-able and that the expense stay below the $6000 received for the project from the Animal Welfare Enhancement Award. Ultimately, by using resources already available to us, we were able to manage the time and effort required without affecting the normal daily functioning in the labo-ratory.The space designated for the enrichment room had been constructed as an animal housing room (i.e., wall and floor surfaces met Guide standards; air was vented externally), and all environmental aspects (e.g., tempera-ture and humidity) were controllable by laboratory per-sonnel. The space was not needed for housing animals when the project began. The room has 145.8 square feet of floor space (663.5 cubic feet of total space), a fully functional sink, and a steel railing on three walls.A door had to be constructed such that baboons would be able to be safely transferred in and out of the room using the shuttle system described below. In order to accomplish this without permanently altering the room, a door measuring 83.25” by 47.25” was made of aluminumsheets in a frame of 3” x 1.25” 6061 architectural alumi-num, and installed in the existing door frame in front of the existing door (see Figure 1). A sub-frame containing a portion of the front wall of an old baboon cage was mounted in the center of the new aluminum door and welded to the larger door frame such that the shuttle cage could be connected to the embedded guillotine-style door. Once the shuttle is attached, the guillotine-style doors on the shuttle cage and the new “cage front” door are opened and the baboon is able to pass from the shuttle into the room. The cage front door is shut behind the baboon. When a baboon is not in the room, the aluminum door functions as any door would, allowing personnel into theroom so that it may be cleaned between baboons.Figure 1: The door constructed to safely transfer baboons in and out of the enrichment room.A painted wooden structure was also manufactured to block baboon access to the sink and its pipes (see Figure 2).The structure is hinged at the front, allowing easy ac-cess to the sink by personnel; fasteners prevent the baboon from opening the lid to the sink. Electrical outlets were covered with metal plates that were screwed in over them. Experimental Design and Procedures: The psychologi-cal well-being of nonhuman primates must be based on individual needs, thus a single-subject design was used in which each subject served as his own experimental control (Sidman, 1960). A subject’s target behavior was meas-ured before the intervention (i.e., exposure to enrichment room) and then measurements in the home cage continued as baboons were periodically exposed to the enrichment room. Prior to any enrichment room exposure, the fre-quency of the target behavior in the home cage was re-corded using a time-sampling procedure (Martin & Pear, 1992) in which 2-minute observations were conducted every hour for 8 hours (i.e., every hour from 7 a.m. to 3 p.m.) at least three days a week, over at least three weeks (i.e., a minimum of 72 two-minute observations). After subjects began spending time in the enrichment room, the home cage observations occurred once per week on a day when the baboon was not scheduled to be in the enrich-ment room (e.g., eight 2-minute observations on Fridays). Figure 2: A baboon in the enrichment room. The wooden structure on the left is the painted and hinged structure used to block baboon access to a sink located in the enrichment room. Shown in the picture are various types of plastic zoo balls, plas-tic tires, tree branches, mirrors, plastic chains, and cardboard for shredding. In addition, small food items (e.g., raisins, peanuts, cashews, popcorn, sunflower seeds, etc.) are placed throughoutthe room to encourage foraging behavior.The frequency of behaviors was recorded by the ob-server marking a behavioral checklist that included the following behaviors: pacing, rocking, bouncing, circling, self-biting, self-grooming, sleeping, huddled posture, masturbating, aggressive behaviors, playing with toy, lip-smacking, grunting, eating, and drinking. Similar behav-iors have been defined previously in our lab as a part of assessments to examine acute and chronic drug effects (Ator et al., 2000; Goodwin et al., 2005; Goodwin et al., 2006).Three baboons (BB, DC, and SY) were identified as exhibiting behaviors in their home cages for which a de-crease in the frequency may indicate improvement in psy-chological well-being. For baboon BB, the behaviors were pacing and circling in his home cage. For baboons DC and SY, a “huddled” posture, operationally defined assitting with chin on chest and being unresponsive to nor-mal stimuli (e.g., our saying his name or offering food treats), was identified as such a behavior. In addition, baboon SY was identified as engaging in excessive grooming. For all three baboons, manipulating items/toys provided in the home cage was identified as a behavior for which increases in frequency may signal improve-ments in psychological well-being and was also recorded.Periodic cage washes (e.g., every two weeks) require baboons to be transferred out of their home cages and into a temporary cage via a “shuttle”. After the shuttle is at-tached to the front of a baboon’s home cage, the guillo-tine style doors on the cage front and shuttle front are lifted and the baboon is able to enter the shuttle. The doors are then shut, and the baboon is transferred to a temporary cage while his home cage is washed. The same procedures are used to transfer the baboons back to their home cages. Although most baboons readily par-ticipate in this procedure, some baboons consistently re-quire coaxing to enter the shuttle. Typically, veterinary technicians attempt to coax baboons into the shuttle by placing fruit in it, and when this fails, the back wall of the home cage is cranked forward so baboons have no choice but to enter the shuttle. In these extreme situations, ba-boons may experience some level of stress associated with the cage wall being cranked forward.Three baboons (CY, DE, and SC) from the colony were identified as consistently required coaxing and/or cranking of the back wall in their home cage in order to transfer them in the shuttle for routine cage washes. De-creasing the time taken for these baboons to enter the shuttle was presumed to lower the stress levels experi-enced by these baboons when they require such transfer.Exposure to the enrichment room began after pre-intervention data had been collected. Between 7 a.m. and 12 p.m. (i.e., prior to daily feedings), individual baboons were transported from their home cages to the enrichment room in the shuttle 2-3 times per week. Two dependent variables were used to measure the effectiveness of expo-sure to the enrichment room:1.Target Behaviors: For baboons BB, DC, and SY, the frequency of the behavior(s) identified for each baboon as described above (i.e., circling/pacing, huddled posture, excessive grooming, and handling toys) were systemati-cally recorded by a trained observer before any subject entered the room (i.e., in the weeks prior to entering the enrichment room the first time) using checklists described above.2.Shuttle Behavior: For baboons CY, DE and SC, the latency to enter the shuttle for transportation was re-corded in multiple instances before any exposure to the enrichment room; recording continued after exposure to the enrichment began. The maximum latency to enter the shuttle voluntarily was defined as five minutes, after which time the back wall was cranked forward to leave the baboon with no choice but to enter the shuttle.Each baboon spent 30 minutes in the enrichment room where he had access to numerous objects and toys manu-factured or otherwise suggested for nonhuman primates, including tires, various types of plastic balls, trees, mir-rors, wood pieces, knotted ropes, plastic chains, etc. (see Figure 2; Bio-Serv, Frenchtown, NJ; Desert Plastics, Al-buquerque, NM; Otto Environmental, Milwaukee, WI; Primate Products Inc., Woodside, CA; and Steiner Enter-prises, Lafayette, IN). The same objects were kept in the room, but were cleaned and arranged differently between baboon visits. In addition, small food items (e.g., raisins, peanuts, cashews, popcorn, sunflower seeds) were placed throughout the room for each baboon to encourage forag-ing behavior. The objects manipulated and duration spent in the enrichment room were recorded for each baboon.After 30 minutes, the shuttle was pushed up against the guillotine door to the room and the doors on the shut-tle and the cage door were raised for transportation to the home cage. Baboons typically returned readily to the shuttle. If a baboon did not do so, a technician placed a piece of fruit in the shuttle to coax the baboon into it. As noted above, daily feeding (i.e., primate biscuits and fresh produce) was restricted to post-enrichment room partici-pation, to increase the likelihood that baboons resisting entering the shuttle might be coaxed with the fruit.Data Analysis: Data are presented for individual ba-boons. As subjects were also participants in on-going behavioral pharmacology studies, only data collected on days when no drugs were administered were included in this data analysis. As described above, a time-sampling procedure was used to assess the frequency of a specific behavior in the home cage for any given day Martin & Pear,1992).Thus, the total number of episodes across the eight 2-min.observations (one each hour for eight con-secutive hours)that occurred in one 24-hr period was av-eraged across days for the periods before and after en-richment room exposure. In addition, the 2-min. observa-tions were combined within each day by adding the fre-quency of occurrences of any given behavior and then dividing the total frequency by the number of total min-utes spent observing in order to express a rate. In this way, the rate for each day served as an independent ob-servation for comparing frequencies before and during exposure to the enrichment room using Student’s t-test (one-tailed).For the individual latencies to enter the transport shuttle, logarithmic transformation of individual latencies were analyzed using Student’s t-test (one-tailed). Changes in the mean frequency of a specific behavior, or the mean latency to enter the shuttle, were deemed statis-tically significant at the 0.05 level or better for individual baboons after exposure to the enrichment room.The data are also presented in graph form as (1) the mean (±SD) frequency of each measure for each baboon prior to any exposure in the enrichment room (PRE) and (2) the frequency of that measure following each expo-sure to the room. In this way, patterns of change over time as a result of repeated exposure to the enrichment room may be detected.ResultsFor baboon BB, repetitive pacing/circling in the home cage was identified as the target behavior prior to the start of this study. Using the time-sampling procedure de-scribed above, the mean (±SD) frequency of pac-ing/circling episodes in the home cage prior to any visits to the enrichment room was 2.19 (±1.39) (see Figure 3). After exposure to the enrichment room, the mean (±SD) number of pacing/circling episodes significantly de-creased to 0.643 (±0.63) (t=3.948; p=0.0002).Figure 3: The mean frequency of pacing/circling episodes per two-minute interval in the home cage of baboon BB. Data here, and in Figures 4, 5, and 6, are the mean (±SD) frequency ob-tained using a time-sampling procedure before exposure to the enrichment room (PRE), and the frequency observed following exposure to the enrichment room.For baboons DC and SY, a “huddled” posture was identified as a target behavior for which a decrease fol-lowing exposure to the enrichment room may indicate an improvement in psychological well-being (see Figure 4). As noted previously, the “huddled” posture is defined as sitting with chin on chest and being unresponsive to nor-mal stimuli. For baboon DC, the mean (±SD) frequency of the “huddled” posture prior to exposure to the enrich-ment room was 5.25 (±1.29). The mean frequency after exposure decreased to 4.21 (±1.31), a statistically signifi-cant decrease (t=2.02; p=0.03; see Figure 4). For baboon SY, the frequency of “huddled” posture observed in the home cage also decreased after exposure to the enrich-ment room. Prior to the first exposure to the enrichment room, the mean (±SD) frequency of a “huddled” posture for SY was 1.88 (±1.37). This was significantly de-creased to 0.71 (±0.83) (t=2.92; p=0.003).Figure 4: The mean frequency of “huddled” posture per two-minute interval in the home cages of baboons DC and SY.Excessive grooming was also identified as a target behavior for baboon SY for which a decrease in the fre-quency may signal an improvement in his psychological well-being (see Figure 5). The mean (±SD) frequency of grooming episodes prior to exposure to the enrichment room was 3.77 (±1.45). The mean (±SD) frequency of grooming episodes after exposure decreased to 2.36 (±0.74), a statistically significant decrease (t=3.34;p=0.0008).Figure 5: The mean frequency of grooming episodes per two-minute interval in the home cage of baboon SY.Figure 6: The mean frequency of episodes of “playing with toys” per two-minute interval in the home cage of baboon BB.Behaviors for which an increase in frequency might signal improved psychological well-being were also char-acterized. For baboon BB, there was a significant in-crease in the frequency of “playing with toys” in his home cage after exposure to the enrichment room (t=4.48; p<0.0001). As shown in Figure 6, the frequency since exposure to the enrichment room generally increased. Prior to enrichment room exposure, the mean (±SD) fre-quency of baboon BB “playing with toys” in the home cage was 2.27 (±1.91). After the first exposure, the mean (±SD) frequency was 4.9 (±1.54).Figure 7: The mean (±SD) latency (min.) to enter the shuttle from the home cages of baboons DE and CY before (PRE) ex-posure to the enrichment room and after exposure. The maxi-mum latency was five min., after which the back wall of the home cage was cranked forward.Some of SY’s and DC’s behaviors in the home cage that may signal improvement in psychological well-being when increased (i.e., playing with toys, lip smacking, and grunting) were not significantly changed (data not shown) after exposure to the enrichment room.The latency to enter the shuttle for transportation from the home cage to the enrichment room was studied in three baboons (DE, CY, SC) known to require coaxing, and often cranking the back wall of the home cage, to get them into the shuttle. As shown in Figure 7, baboon DE required a mean (±SD) latency of 3.45 (±1.82) minutes to enter the shuttle prior to any exposure in the enrichment room. After the first exposure, the mean latency to enter the shuttle significantly decreased (t=7.4; p<0.0001). For baboon CY, the mean (±SD) latency to enter the shuttle prior to exposure was 0.53 ± 0.57 minutes, a significant decrease after exposure (t=2.1; p=0.023).Despite coaxing with fruit, one baboon (SC) failed to return to the shuttle after entering the enrichment room. Fortunately, the baboon was one who readily pressed his thigh up against the bars for ketamine injections in the home cage and also did so in the enrichment room. While ketamine is routinely used in lab settings for its sedative effects, it is a drug with potential for abuse, and studies have illustrated that nonhuman primates will self-administer ketamine (Lukas et al., 1984; Moreton et al., 1977). Thus, since intramuscular ketamine clearly served as a reinforcer for this baboon, the veterinary technician was able to sedate the animal with ketamine in order to remove him from the room. When this also needed to be done at the end of his second visit to the room, this ba-boon was dropped from the study.DiscussionThe objective of the present study was to improve the quality of life for baboons in our lab through exposure to an expanded environmental enrichment program. We could not simply assume, however, that exposure to the enrichment room would result in an improvement in the psychological well-being of our subjects. Thus, we iden-tified three baboons with maladaptive behaviors in their home cages and compared the frequency of these behav-iors prior to enrichment room exposure to the frequency of the same behaviors after exposure, and found signifi-cant decreases in their frequency.In addition, we found that two baboons would more readily enter the transport shuttle after exposure to the enrichment room. That is, the stress resulting from crank-ing the back wall forward and “forcing” baboons out of the cage and into the shuttle for transport no longer oc-curs for these baboons, since they now readily enter the shuttle. This is important because baboons must be trans-ported out of their home cages for regular cage washes.Thus, our data support the idea that exposure to the enrichment room improved the psychological well-being of the baboons. In addition, while only one of the ba-boons showed an increase in the use of toys in his home cage, it is possible the baboons experienced significant increases in their psychological well-being that were un-detected by our outcome measures. Moreover, by docu-menting the smaller objects manipulated (e.g., Kong® toys, balls made of different materials, plastic chains, mirrors) while the baboons were in the enrichment room, we also were able to identify individual toy preferences for individual baboons. This has resulted in more effec-tive enrichment being provided in the home cages.Another goal was simply to increase the amount of activity in which the baboons were able to engage. Tech-nicians consistently noted in the records that baboons spend a majority of time in the enrichment room moving around and “exploring.”A discussion of promoting the psychological well-being of nonhuman primates in laboratories would not be complete without mentioning possible causes of abnormal cage behaviors. While it is not possible to know why one baboon engages in maladaptive behaviors when others do not, one theory with an abundance of evidence asserts that removing an infant from his mother’s care too soon can result in the formation of abnormal cage behaviors later in life (Altmann, 2001; Bellanca & Crockett, 2002). Neither information about the age at which a baboon was removed from his mother’s care, nor descriptions of early life experiences, are routinely provided with nonhuman primates upon arrival at research facilities. For example, while the actual age of baboon BB is not known, he was a wild-caught baboon who weighed a mere 8.2 kg and was lacking his canine teeth upon arrival, leaving no doubt he arrived as a juvenile. Moreover, when he arrived at quar-antine (and for a period of time after arriving in our facil-ity), BB was housed with a second male baboon that was bigger and dominated BB. Thus, the cage behaviors ex-hibited by BB later in life may have been shaped as a consequence of being taken from his mother too soon and/or being caged with a dominant older male early in life. While many factors certainly influence the formation of maladaptive behaviors, housing and rearing conditions, early life experience, and colony procedures clearly play a role. Indeed, a retrospective analysis in a colony of rhesus macaques concluded that factors influencing the development of stereotypic and self-injurious behaviors in rhesus macaques included intrinsic factors (i.e., males exhibit more maladaptive behaviors than did females), rearing conditions, housing conditions, colony manage-ment practices, and research protocols (Lutz et al., 2003). Regardless of the cause of abnormal cage behaviors, it is important to examine how environmental enrichment may be useful for decreasing these behaviors.Since we ended our data collection, the enrichment room has been available for all baboons in our colony, and we have encountered baboons that do not readily return to the shuttle for transportation back to their home cages. Specifically, we have had three instances, other than the one reported above, when baboons would not readily exit the enrichment room. In these instances, the technicians tried to coax the baboon into the shuttle by placing fruit in it, but found it required considerable time before the baboons would exit. That is, after a period of 1-4 hours baboons eventually returned to the shuttle, and those baboons are not currently visiting the enrichment room. Other methods for encouraging return to the shut-tle, however, are being tried. For example, we have found that turning off the room light was successful with one baboon. Based on our experience during and after the present study, 30-45 minutes seems to be the ideal amount of time in the room after which the majority of baboons will readily exit the room without incident.It is our hope that other laboratories will use an en-richment room for caged nonhuman primates and will find it a valuable tool for increasing their psychological well-being. Facilities that house very large numbers of nonhuman primates may find it difficult to expend the time, space, and money to offer such enrichment to all animals. While it would be wonderful to give all the animals in a lab access to an enrichment room, it would not be as expensive to at least provide it to those animals who need it most. Indeed, our data support the notion that the psychological well-being of nonhuman primates exhibiting maladaptive behaviors can improve by expo-sure to an enrichment room.It should be noted, however, that some unique vari-ables may have contributed to our success. The veteri-nary technicians in the Division of Behavioral Biology are responsible for the daily care of the same animals, and the baboons serve as subjects in behavioral experiments for a number of years (i.e., studies are not terminal). Thus, the baboons are extremely familiar with their vet-erinary technicians. In addition, the baboons have a his-tory of shuttling for cage washes and so the act of moving from their home cages to the enrichment room was famil-iar to them. Nonetheless, exposing baboons with target behaviors indicative of poor psychological well-being to the enrichment room resulted in an apparent improvement in psychological well-being. The ease of replication of the enrichment room in other nonhuman primate colonies is contingent on the availability of space, time, and some financial support.In conclusion, participation in the expanded enrich-ment program enhanced the standard enrichment provided in the home cages, and also appeared to improve the psy-chological well-being of individual baboons with identi-fied maladaptive behaviors in our research program. We。

Analysis of clothing supply chain: Integration & Marriage of Lean &AgileBy Mandeep SainiContentsIntroduction 1 Lean and Agile Supply Chain 1 Particular ways of marring lean and agile paradigms 5 The Pareto Curve approach 6 The Decoupling Point 7 Separation of Base and Surge Demand 8 Case: Benetton 8 Case: Hennes & Mauritz (H&M) 10 Case: Zara 12 Conclusion 14List of TablesTable (1): Usage of Lean and Agile 2 Table (2): Difference in Lean and agile 3 Table (3): Market Winner and Qualifier Matrix 4 Table (4): Benefits of Leagile 5List of FiguresFigure (1): The Pareto Curve approach 6 Figure (2): The Decoupling Point 7 Figure (3): Base and Surge Demand 8 Figure (4): Traditional Lean manufacturing process of garments 9 Figure (5): Benetton’s Manufacturing Process 10 Figure (6): H&M’s Supply Chain Model 12 Figure (7): Flow of Information at Zara 13IntroductionModern supply-chains are very complex, with many analogous physical and information flows occurring in order to certify that healthy products are delivered in the right quantities, to the right place in a cost-efficient manner. The current drive towards more efficient supply networks during recent years has resulted in these international networks becoming more vulnerable to disruption. To be precise, there often tend to be very little inventory in the useful professional organisation to buffer interruptions in supply and, therefore, any disruptions can have a rapid impact across the progressive supply networks. This paper contains the significant issues of modern clothing supply chain. Due to globalisation, of rapidly changing markets and vogues of clothing business make it specified in terms of stylish fashion and changing user behaviour. The fashion industries are changing and expending the business while outsourcing; based on shortest lead times. But now, as per the case study “Supplying Fashion Fast” today’s supply chain are not to just serving the market with shortest lead time but it is to react immediately on the demand. . The challenge faced by a supply chain delivering fashion products is to develop a strategy that will improve the match between supply and demand and enable the companies to respond faster to the marketplace”(Naylor, Towill and Christopher, 2000).Lean and Agile Supply chainFor over a decade, companies have been achieving huge cost savings by streamlining their supply chains. While affluent, and thus pleasurable; these trends have also exposed organisations to new sets of paradigms such as Lean, Agile, Integration of Lean and Agile, Relationship driven supply chain etc. The question arise here is, Why there is a need to integrate the lean and agile supply chain? To find the answer the previous pages need to be turned; "Lean" is the name that James Womack gave to the Toyota Production System in the book “The Machine that Changed the World.” Lean was the term that best described Toyota's system versus the rest of the world's automotive manufacturers at the time. Many companies have since applied lean thinking to their organizations withvarying degrees of success. Applying lean to the entire supply chain is not a new concept, but very few have had success doing it. Naylor et. al (1999) defined the lean as, “Leanness means developing a value stream to eliminate all waste including time, and to enable level schedule.” Further the Agility means “using market knowledge and virtual corporation to exploit profitable opportunities in a volatile marketplace.” The leanness is basically to eliminate the waste with in the manufacturing to drive the lowest possible cost and highest quality of the product. Agility is to use the Voice of Customers (VOC) to develop new products to satisfy the demand, this is more flexible and high cost then leanness. “In lean production, the customer buys specific products, whereas in agile production the customer reserves capacity that may additionally need to be made available at very short notice” (Naylor, Towill and Christopher, 2000). Please see Table (1) for the use of lean and agile supply chain and Table (2) for differentiate the lean and agile supply chains. The tables developed by the author to demonstrate the difference, usage and benefits of Lean, Agile and Leagile supply chain paradigms. The table 1, 2 and 4 are influenced by the suggestions by the previous researchers such as Christopher, (2000), Towill, Christopher and Naylor (2000), Crocker & Emmett (2006), Naylor, Naim & Berry (1999) and the other literature found.Table: (1)Usage of Lean and AgileLean•Fluent Manufacturing•Zero inventory•Just in Time (JIT)•Remove waste•Vendor Managed Inventory (VMI)•Total Quality Management (TQM)•Economies of Scale (Low cost)•Commodities•Continuous, Line and High Batch production processAgile •Postponement•Collaborative scheduling•Just In Time (JIT)•Purchasing input capacity (PIC)•Supplier Trade off (Setup Vs Inventory)•House of Quality (HOQ)•Made to Order (High Cost)•Fashion Products•Integration of Micro and Macro environment•Project, Jobbing and low batch processSource: The Present AuthorTable: (2)Difference in Lean and AgileLean •Containing little fat•Product oriented•Reduce stock to minimum•Plan ahead•Satisfy customers by eliminating waste•Measuring output criteria: Quality, Cost and Delivery•Low Cost•Efficiency•Less flexible•Low varietyAgile•Nimble•Customer oriented•Reducing stock in not an issue •Unpredictable demand planning •Satisfy customers by configuring order•Measure output Criteria: Customer satisfaction•High Cost•Effectiveness•High flexible•High varietySource: The Present AuthorAs per the case study “Supply Fashion Fast” the fashion market is volatile and customer driven. Towill and Christopher (2002) suggested the market qualifier and winners in Lean and Agile supply chain (See Table 3). In Agile supply chain the market qualifiers are Quality, cost and lead time and the winner is who produce the high service level. But in Lean supply, the market qualifiers are Quality, Lead time and Service level and the winner is the cost. In addition; Naylor, Towill and Christopher (2000) suggested that agile supply chain is for fashion goods and lean supply chain is for commodities (See Table 3). Now the concept of integration of lean and agile paradigms is originated to capturing the advantage of lean and agile paradigms such as to maximize the efficiency and utilization of the operations and customization of high level of products. Christopher and Towill (2002) pointed that, “the lean concept works well where demand is relatively stable and hence predictable and where variety is low.” Furthermore “Agility is a business wide capability that embraces organisational structure, information systems, logistics process and in particular mind sets.”Table: (3)“Fashion products have a short life cycle and high demand uncertainty, therefore exposing the supply chain to the risks of both stock out and obsolescence. A good example of a fashion product is trendy clothing (Naylor, Towill and Christopher, 2000). To avoid degeneration and to fulfill the high demand uncertainty there is a need to combine the lean and agile to getting the best out of them.This combined approach is known as `Leagility’ and, as it is packed with the best outcomes of lean and agile. Resultant; the integration of lean and agile supply chains can thereby adopt a lean manufacturing approach upstream, enabling a level schedule and opening up an opportunity to drive down costs upstream while simultaneously still ensuring that downstream should have an agile response capable of delivering to an unpredictable marketplace. The need of integration or marring the lean and agile supply chain is to react effectively on a volatile demand while reducing waste and cost and improving quality and service level. Please see table (4) for benefits of ‘Leagile’ supply chain.Table: (4)Benefits of Leagile•Control & view inventory levels across a network•Manage orders between trading partners•Organise collaborative demand plans•Plan replenishment across an internal or external network•Enable Sales and Operation Planning•Monitor and Alert on significant events•Managing JIT approach•Managing Vendor Managed Inventory•Quick response to market•Achieve benefits of postponement•Standardisation of products•Converting voice of customers (VOC) into productsSource: The Present AuthorPractical ways of marring Lean and agile paradigmsThere are particularly three ways of marring lean and agile paradigms suggested by researchers such as, Pareto Curve approach, Decoupling Point and base and surge demand. These three ways of marring lean and agile can be used in any point of time and in any department, such as design, procurement, manufacturing etc. In a particular supply chain these approaches can be used frequently, such as Pareto 80/20 rules and separation of base & surge demand can be used in design, manufacturing, forecasting or while taking the critical decisions such as Standardisation of products, postponement decision etc. These approaches give flexibility to the process and enable to postpone the decisions and lower the inventory and most importantly minimizing the waste while optimizing the performance and quality. De-coupling point approach is the main idea to hold the inventory in shape of incomplete product shape and assemble the products instantly or in a shortest period on customers demand. The Dell computer is a well know example of decoupling approach practice. Practical implication of these approaches gives the benefit of integration of lean and agile supply chain. The practical ways of marring lean and agileprovide available and affordable products, (Christopher & Towill, 2001) instantly to the customers in a volatile demand such as Fashion.Figure (1): The Pareto Curve approachSource: Christopher and Towill (2001)In the late 1940s quality management guru Joseph M. Juran suggested the principle and named it after Italian economist Vilfredo Pareto, who observed that 80% of income in Italy went to 20% of the population. Pareto Analysis is a statistical technique in decision making that is used for the selection of a limited number of tasks that produce significant overall effect; stated Towill, Naylor, Jones (2000), Christopher, Towill (2001) Haughey, (2007). It uses the Pareto Principle; is also know as the 80/20 rule, the idea that by doing 20% of the work you can generate 80% of the benefit of doing the whole job (Haughey, 2007). This rule can be applied on almost anything such as 80% delays arise from 20% of causes, 20% of system defects caused 80% of problems (Towill, Nayloy, Jones, 2000). “The Pareto Principle has many applications in quality control. It is the basis for the Pareto diagram, one of the key tools used in total quality control and Six-Sigma”(Haughey, 2007). In figure (1) Christopher and Towill (2001) suggested that, 20% of theproducts are easily predictable and can be standardised and they lend themselves to lean manufacturing, furthermore the 80% of the products are in agile manufacturing because of less predictability, which require quick response to market”Decoupling pointThe further marring of lean and agile can be achieved by creating decoupling point; in a production process it is common to introduce decoupling points where production lead time is much longer then acceptable order lead time (Christopher and Towill, 2000). The decoupling point takes physical stock to achieve the advantage of different management and control tools to efficiently manage the both side (input & output) of the inventory (Velde and Meijer, 2007). The other side of decoupling point is the natural boundaries of organisations and departments with in the process (Christopher and Towill, 2001, Velde and Meijer, 2007). It is also the hub to meet the need and capability on either side of point. With in a supply chain there can be many numbers of decoupling points (Towill, Naylor and Jones, 2000). “A decoupling point divides the value chain into two distinct parts; one upstream with certain characteristics and one downstream with distinctly different characteristics”(Olhager, Selldin and Wikner, 2006). In figure (3) Christopher and Towill (2001) suggested that, “by utilising the concept of postponement companies may utilise lean method up to decoupling point and agile method beyond that.”Figure (2): The Decoupling PointSource: Christopher and Towill (2000)Separation of Base and Surge DemandSeparating demand patterns into “base” and “surge” elements is an employment of hybrid strategy. “Base demand can be forecast on the basis of past history whereby surge demand typically cannot. Base demand can be met through classic lean procedures to achieve economies of scale whereas surge demand is provided for through more flexible and probably higher cost, processes” stated (Christopher and Towill, 2001). Further Christopher and Towill pointed that; in fashion industry base demand can be sourced in low cost countries and surge demand to be topped up locally”. Base demand can be achieved by classical lean manufacturing with low cost and less flexibility and surge demand by agile with high cost and high flexibility.Figure (3): Responding to combinations of ``base'' and ``surge'' demandsSource: Christopher and Towill (2001)Case: United Colors of BenettonThe Benetton Group exists in 120 countries, with around 5000 stores and produce revenue of around 2 billions. According to the case study the group employees 300 designers and produces 110 million garments a year. The group owns most of the production units in Europe, North Africa, Eastern Europe, and Asia. 90% of the garments are being produced in the Europe and the group invested in highly automated warehouses, near main production centres and stores. Benetton’s stores sell mixed brands, such as the casual wear, fashion oriented products, leisure wear and street wear and the flash collections during the seasons. More then 20% of products are customised to the specific need of each country and reduced by 5-10 percent by standardising the products and strengthening the global brand image and reducing production cost.According to case study Benetton’s goals are to achieve expansion of sales network while minimizing the cost and increase the sales of fashion garments. In order to achieve these goals a higher degree of flexibility is require in the process. But its very hard to achieve flexibility, as the lead times are long; in respect retailers are required to purchase in advance, and the most of the purchase plans are depends upon the generalising the orders. For example; if Benetton needs to wait for a specific number of orders from retailers to buy the fabric in bulk and start manufacturing in order to minimise the cost, but resultant the process will increase the lead time of the finished product in store. See figure (4) for a traditional (lean) manufacturing process of garments.Figure (4): Traditional (Lean) manufacturing process of garmentsSource: The Present AuthorAccording to the case study Benetton the need of fashion industry is the quick response to the market. This requires a higher degree of flexibility in production and decision making. As per the corporate goals of the group, Benetton acquires the strategy of postponement and standardisation of the products. The benefit of the postponement is to enables Benetton to start manufacturing before color choices are made, to react on customer demand and suggestion and to delay the forecast of specific colors. Further more; the product and process standardisation benefits the Benetton with the lower setup cost, manufacturing before dying and give flexibility to produce only a subset of the products.Figure (5): Benetton’s manufacturing processSource: The AuthorIn figure (4) and (5) the manufacturing process is changed due to the dying finished products, in respect of the change in process the setup cost of manufacturing garments parts can be reduced further more the inventory level can also be reduced because the postponement of decision of dying the garments after manufacturing reduced the requirement if keeping much stock of different color of garments. Additionally; postponement is helping the Benetton to produce the fabric under lean manufacturing process while reducing and eliminating cost and waste. It also involves the flexibility to produce variety of colors in a short lead time. This also helped the Benetton to standardise the manufacturing process and further led to gain cost leadership and differentiation strategies. In the context; Dying unit is acting as a decoupling point where the lean manufacturing exists downstream of information flow and agility upstream.As per the case study The Benetton’s 90% of the production is based in the Europe and rest in low cost countries. Here the Pareto 80/20 rule can be applied because 90% of the production is based on to fulfill the surge demand, and the prompt actions can be made on the volatile demand. Reducing the number of customised products by the Benetton is also an attempt to increase the number of standardised products in order to achieve the lowest cost possible and make the product a global brand. The other reason is to gain the benefits of level scheduling of base and surge demand to ensure the usage of capacity.Hennes & Mauritz (H&M)As per the case study and H&M internet media; H&M collections are created and placed centrally in the design and buying department to find the good balance of threecomponents Fashion, Quality and the best Price. H&M is a customer focused company and employees more then 100 designers. A team of 500 people works together to built the range and putting together the colors, fabrics, garment types and theme and provide a feel for new season’s fashion. Furthermore; H&M do not own any manufacturing units, they have more then 700 suppliers in the Asia and Europe, but H&M owns the production offices working closely with the suppliers and ensuring the safety and quality of goods. H&M’s lead time varies 2 weeks to 6 months based on the item. The main transit point of goods is in the Hamburg and company got more then 1500 own stores.As per the company’s business concept Fashion, Price and Quality; H&M produce most of the garments outside Europe to achieve the benefits of leanness. They buy fabric in advance as per the forecast in order to minimise the cost (Li Li, 2007). The production offices situated with in the origin of production act as the second hub of information flow downstream and ensure the quality and the work standard of the suppliers. The other reason of placing production offices is to maximise the efficiency of supplier to achieve the lowest cost and zero defects in the products and minimise the lead time. The transit point in the Hamburg works as a decoupling point, while managing the flow of goods and information upstream and downstream. As H&M is a customer oriented company and learning from customers and serving the surge demand by production in the Europe (Li Li, 2007). The author is tried to develop a model of H&M supply chain to illustrate the particular ways of marriage of lean and agile. To illustrate in easiest way the author had put only one supplier in the Asia and one in Europe, to make it easier the inventory points, are not also explained (see figure 6).Figure (6): H&M SC Model.Source: The AuthorCase: ZaraAs per the case study; under the Zara model, the retail store is the eyes and ears of the company. Instead of relying solely on electronically collected data, Zara utilizes word-of-mouth information to understand more about their customers. Empowered store managers report to headquarters what real customers are saying. Products that are not selling well are quickly pulled and hot items quickly replenished. Their quick turn around on merchandise helps generate cash which eliminates the need for significant debt.Zara hires young designers and trains them to make quick decisions. Decision-making is encouraged and bad decisions are not severely punished. Designers are trained to limit the number of reviews and changes, speeding up the development process and minimizing the number of samples made.Figure: (7) Flow of information at ZaraSource: The Present AuthorAs per the literature available on Zara supply chain and the use of technology the author tried to develop the Figure (7). In the figure it is illustrated that the Zara supply chain starts from the retail stores and customers, the use and flow of information made Zara to convert the high degree of information into opportunity. The agility here is that the stores get feedback from customers and send the feedback to design team. Design team based on the fabric availability design the products by using the “Vanilla Box Design”. Thishelps to make computerised designs instead to waste money and time in making actual samples. Zara is using Pareto 80/20 rule while choosing the designs to send into production. The design team sends the information to cutting department and fabric department to ensure the right pattern is produced, here in production Zara is using the lean manufacturing in specialized factories while standardisation of cutting, stitching and dying process, pointed; Anderson, (2007) Machouca, Lewis and Ferdows, (2005). Un-dyed fabric is produced in advance with the help of long term forecast. Design teams make sure they will only design the garments keeping in mind the availability of specified fabric. The other advantage of integration of all the departments is gaining the benefit of postponement; Zara is dying the finished garments as per the customer’s reaction. Surge demand is managed by producing goods in Europe and base demand in other labor intensive countries (Machouca, Lewis and Ferdows, 2005).ConclusionThe need of supply fashion fast in the volatile demand; led companies such as, Zara, H&M & Benetton to make the changes in lean and agile process and integrate the both to achieve the benefits of lean and agile. The main motive to achieve the leagile is to react fasted on the changing demand. This requires a better control and view of inventory levels across the network, enable sales and replenishment planning across the internal and external network. With the help of IT, Zara achieved the control and monitoring the different event on the market, they are able to act on with the quick response to the market. Zara and Benetton both achieved the benefits of postponement. All there companies achieved the benefits of standardisation. Although; Zara, Benetton and H&M, took the different approach to marring the lean and agile but the overall purpose is the same; “Supply Fashion Fast” with lowest possible price and highest degree of quality.The Figures (4) & (5) Benetton; (6) H&M and (7) (Zara) is developed by the author with the help of the data found on the company website and based on articles and journals of Davanzo, Starr and Lewinski (2004);Machouca, Lewis and Ferdows, (2005); Anderson, (2007); Anderson and Lovejoy (2007); Li Li (2007) and Claburn (2007).ReferencesAnderson K., Lovejoy J.; (2007); The Speeding Bullet; Zara Apparel Supply Chain; March 2007; accessed 06th Dec. 2007; Source:/thelibrary/speeding.htmlAnderson K.; (2007); Fast Fashion Evolves; March 2007; accessed 06th Dec. 2007; Source: /thelibrary/speeding.htmlClaburn T; (2007); Math Whizzes Turbo-Charge an Online Retailer's Sales; 05th Oct. 2007; accessed: 06 Dec. 2007; Source:/info_centers/supply_chain/showArticle.jhtml?articl eID=202300213Christopher, M. and Towell, D.R. (2000): “Supply Chain migration from lean and functional to agile and customized”. Supply Chain Management, Vol. 5 – No. 4 – pp. 206-213.Christopher, M. and Towill, D. (2001), An integrated model for the design of agile supply chains, International Journal of Physical Distribution & Logistics Management , Vol. 31 No.4 , pp.235-246Christopher M. and Towill D; The Supply Chain Strategy Conundrum: To be Lean or Agile or to be Lean and Agile; International Journal of Logistics: Research and applications; Taylor & Francis Ltd; 2002; Vol. 5; No. 3; ISSN 1367-5567Davanzo R. L, Starr C.E and Lewinski H. V;(2004); Supply Chain and the Bottom Line: A Critical Link; Outlook Journal; Feb. 2004; accessed: 05th Dec. 2007; Source:/Global/Research_and_Insights/Outlook/By_Alphabet/Supply Link.htmGilmore D.; (2006); Time for New Supply Chain Icons; 12th Oct. 2006; accessed: 07th Dec. 2007; Source: /assets/FirstThoughts/06-10-12.cfm?cid=771&ctype=contentHaughey D; (2007); Pareto Analysis Step by Step; Accessed 09th Dec 2007; Source: /pareto-analysis-step-by-step.html?gclid=CLy52uKjnp ACFQ2WEgod2zbo7wLi Li: (2007); Fashion Magnates' Supply Chain Contest; 08th May 2007, Accessed 19th Nov. 2007; Source:/index.php?categoryid=Vm10YVlWVXhVbk5SYkVwUlZrUk JPUT09K1M=&p2_articleid=Vm10YWIyUXlTblJWYWs1UlZrUkJPUT09K1M=&p2_p age=2Mason-Jones, R and Towill, D.R. (1997): Information enrichment: designing the supply chain for competitive advantage. Supply Chain Management. Vol. 2, No. 4 – pp. 137-148Mason-Jones, R, Naylor, J.B. and Towill, D.R. (2000): Engineering the leagile supply chain. International Journal of Agile Management Systems. Vol. 2, Iss 1. pp.54Machouca J, Lewis M, Ferdows K; Zara's Secret for Fast Fashion; 21 Feb. 2005; Accessed 18 Nov. 2007; Source /archive/4652.htmlNaylor, J.B, Naim, M.M. and Berry, D. (1999), Leangility: interfacing the lean and agile manufacturing paradigm in the total supply chain, International Journal of Production Economics, Vol. 62, pp.107-18Olhager J, Selldin E, and Wikner J; (2006); Decoupling the value chain; the international journal of value chain management; Vol. 1, No. 1; abstract; Source:/search/index.php?action=record&rec_id=9021&prevQuery =&ps=10&m=orTowill D R., Naylor B. and Jones R M; Lean, agile or leagile? Matching your supply chain to the marketplace;International Journal of Production Research, 2000, VOL. 38, NO. 17, 4061- 4070; ISSN 0020-7543Velde L. N. J and Miejer B. R; (2007); A system approach to supply chain design with a multinational for colorant and coating; accessed 10th Dec. 2007; Source:/mcn/pdf_files/part6_5.pdfWalters D; Demand chain effectiveness – supply chain efficiencies; A role for enterprise information management; Journal of Enterprise Information Management; Volume 19 Number 3 2006 pp. 246-261。

METHOD 8290POLYCHLORINATED DIBENZODIOXINS (PCDDs) AND POLYCHLORINATED DIBENZOFURANS (PCDFs)BY HIGH-RESOLUTION GAS CHROMATOGRAPHY/HIGH-RESOLUTIONMASS SPECTROMETRY (HRGC/HRMS)1.0SCOPE AND APPLICATION1.1This method provides procedures for the detection and quantitative measurement of polychlorinated dibenzo-p-dioxins (tetra- through octachlorinated homologues; PCDDs), and polychlorinated dibenzofurans (tetra- through octachlorinated homologues; PCDFs) in a variety of environmental matrices and at part-per-trillion (ppt) to part-per-quadrillion (ppq) concentrations. The following compounds can be determined by this method:_______________________________________________________________________________Compound Name CAS No a 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) 1746-01-61,2,3,7,8-Pentachlorodibenzo-p-dioxin (PeCDD)40321-76-41,2,3,6,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)57653-85-71,2,3,4,7,8-Hexachlorodibenzo-p-dioxin (HxCDD)39227-28-61,2,3,7,8,9-Hexachlorodibenzo-p-dioxin (HxCDD)19408-74-31,2,3,4,6,7,8-Heptachlorodibenzo-p-dioxin (HpCDD)35822-39-41,2,3,4,6,7,8,9-Octachlorodibenzo-p-dioxin (OCDD) 3268-87-92,3,7,8-Tetrachlorodibenzofuran (TCDF)51207-31-91,2,3,7,8-Pentachlorodibenzofuran (PeCDF)57117-41-62,3,4,7,8-Pentachlorodibenzofuran (PeCDF)57117-31-41,2,3,6,7,8-Hexachlorodibenzofuran (HxCDF)57117-44-91,2,3,7,8,9-Hexachlorodibenzofuran (HxCDF)72918-21-91,2,3,4,7,8-Hexachlorodibenzofuran (HxCDF)70648-26-92,3,4,6,7,8-Hexachlorodibenzofuran (HxCDF)60851-34-51,2,3,4,6,7,8-Heptachlorodibenzofuran (HpCDF)67562-39-41,2,3,4,7,8,9-Heptachlorodibenzofuran (HpCDF)55673-89-71,2,3,4,6,7,8,9-Octachlorodibenzofuran (OCDF)39001-02-0________________________________________________________________________________ aChemical Abstract Service Registry Number1.2The analytical method calls for the use of high-resolution gas chromatography and high-resolution mass spectrometry (HRGC/HRMS) on purified sample extracts. Table 1 lists the various sample types covered by this analytical protocol, the 2,3,7,8-TCDD-based method calibration limits (MCLs), and other pertinent information. Samples containing concentrations of specific congeneric analytes (PCDDs and PCDFs) considered within the scope of this method that are greater than ten times the upper MCLs must be analyzed by a protocol designed for such concentration levels, e.g., Method 8280. An optional method for reporting the analytical results using a 2,3,7,8-TCDD toxicity equivalency factor (TEF) is described.1.3The sensitivity of this method is dependent upon the level of inter-ferences within a given matrix. The calibration range of the method for a 1 L water sample is 10 to 2000 ppq for TCDD/TCDF and PeCDD/PeCDF, and 1.0 to 200 ppt for a 10 g soil, sediment, fly ash, or tissue sample for the same analytes (Table 1). Analysis of a one-tenth aliquot of the sample permits measurement of concentrations up to 10 times the upper MCL. The actual limits of detection and quantitation will differ from the lower MCL, depending on the complexity of the matrix.1.4This method is designed for use by analysts who are experienced with residue analysis and skilled in HRGC/HRMS.1.5Because of the extreme toxicity of many of these compounds, the analyst must take the necessary precautions to prevent exposure to materials known or believed to contain PCDDs or PCDFs. It is the responsibility of the laboratory personnel to ensure that safe handling procedures are employed. Sec.11 of this method discusses safety procedures.2.0SUMMARY OF METHOD2.1This procedure uses matrix specific extraction, analyte specific cleanup, and HRGC/HRMS analysis techniques.2.2If interferences are encountered, the method provides selected cleanup procedures to aid the analyst in their elimination. A simplified analysis flow chart is presented at the end of this method.2.3 A specified amount (see Table 1) of soil, sediment, fly ash, water,sludge (including paper pulp), still bottom, fuel oil, chemical reactor residue,fish tissue, or human adipose tissue is spiked with a solution containing specified amounts of each of the nine isotopically (C ) labeled PCDDs/PCDFs 1312listed in Column 1 of Table 2. The sample is then extracted according to a matrix specific extraction procedure. Aqueous samples that are judged to contain 1 percent or more solids, and solid samples that show an aqueous phase, are filtered, the solid phase (including the filter) and the aqueous phase extracted separately, and the extracts combined before extract cleanup. The extraction procedures are:a)Toluene: Soxhlet extraction for soil, sediment, fly ash, and paper pulp samples;b)Methylene chloride: liquid-liquid extraction for water samples; c)Toluene: Dean-Stark extraction for fuel oil, and aqueous sludgesamples;d)Toluene extraction for still bottom samples;e)Hexane/methylene chloride: Soxhlet extraction or methylenechloride: Soxhlet extraction for fish tissue samples; andf)Methylene chloride extraction for human adipose tissue samples.g)As an option, all solid samples (wet or dry) may be extracted withtoluene using a Soxhlet/Dean Stark extraction system.The decision for the selection of an extraction procedure for chemical reactor residue samples is based on the appearance (consistency, viscosity) of the samples. Generally, they can be handled according to the procedure used for still bottom (or chemical sludge) samples.2.4The extracts are submitted to an acid-base washing treatment and dried. Following a solvent exchange step, the extracts are cleaned up by column chromatography on alumina, silica gel, and activated carbon.2.4.1The extracts from adipose tissue samples are treated withsilica gel impregnated with sulfuric acid before chromatography on acidic silica gel, neutral alumina, and activated carbon.2.4.2Fish tissue and paper pulp extracts are subjected to an acidwash treatment only, prior to chromatography on alumina and activated carbon.2.5The preparation of the final extract for HRGC/HRMS analysis is accomplished by adding 10 to 50 µL (depending on the matrix) of a nonane solution containing 50 pg/µL of the recovery standards C -1,2,3,4-TCDD and 1312C -1,2,3,7,8,9-HxCDD (Table 2). The former is used to determine the percent 1312recoveries of tetra- and pentachlorinated PCDD/PCDF congeners, while the latter is used to determine the percent recoveries of the hexa-, hepta- and octachlorinated PCDD/PCDF congeners.2.6Two µL of the concentrated extract are injected into an HRGC/HRMS system capable of performing selected ion monitoring at resolving powers of at least 10,000 (10 percent valley definition).2.7The identification of OCDD and nine of the fifteen 2,3,7,8-substituted congeners (Table 3), for which a C-labeled standard is available 13in the sample fortification and recovery standard solutions (Table 2), is based on their elution at their exact retention time (within 0.005 retention time units measured in the routine calibration) and the simultaneous detection of the two most abundant ions in the molecular ion region. The remaining six 2,3,7,8-substituted congeners (i.e., 2,3,4,7,8-PeCDF; 1,2,3,4,7,8-HxCDD; 1,2,3,6,7,8-HxCDF; 1,2,3,7,8,9-HxCDF; 2,3,4,6,7,8-HxCDF, and 1,2,3,4,7,8,9-HpCDF), for which no carbon-labeled internal standards are available in the sample fortification solution, and all other PCDD/PCDF congeners are identified when their relative retention times fall within their respective PCDD/PCDF retention time windows,as established from the routine calibration data, and the simultaneous detection of the two most abundant ions in the molecular ion region. The identification of OCDF is based on its retention time relative to C -OCDD and the simultaneous 1312detection of the two most abundant ions in the molecular ion region.Identification also is based on a comparison of the ratios of the integrated ion abundance of the molecular ion species to their theoretical abundance ratios.2.8Quantitation of the individual congeners, total PCDDs and total PCDFs is achieved in conjunction with the establishment of a multipoint (five points)calibration curve for each homologue, during which each calibration solution is analyzed once.3.0INTERFERENCES3.1Solvents, reagents, glassware and other sample processing hardware may yield discrete artifacts or elevated baselines that may cause misinter-pretation of the chromatographic data (see references 1 and 2.) All of these materials must be demonstrated to be free from interferants under the conditions of analysis by performing laboratory method blanks. Analysts should avoid using PVC gloves.3.2The use of high purity reagents and solvents helps minimize interference problems. Purification of solvents by distillation in all-glass systems may be necessary.3.3Interferants coextracted from the sample will vary considerably from matrix to matrix. PCDDs and PCDFs are often associated with other interfering chlorinated substances such as polychlorinated biphenyls (PCBs), polychlorinated diphenyl ethers (PCDPEs), polychlorinated naphthalenes, and polychlorinated alkyldibenzofurans, that may be found at concentrations several orders of magnitude higher than the analytes of interest. Retention times of target analytes must be verified using reference standards. These values must correspond to the retention time windows established in Sec. 8.1.1.3. While cleanup techniques are provided as part of this method, unique samples may require additional cleanup steps to achieve lower detection limits.3.4 A high-resolution capillary column (60 m DB-5, J&W Scientific, or equivalent) is used in this method. However, no single column is known to resolve all isomers. The 60 m DB-5 GC column is capable of 2,3,7,8-TCDD isomer specificity (Sec. 8.1.1). In order to determine the concentration of the 2,3,7,8-TCDF (if detected on the DB-5 column), the sample extract must be reanalyzed on a column capable of 2,3,7,8-TCDF isomer specificity (e.g., DB-225, SP-2330, SP-2331, or equivalent).4.0APPARATUS AND MATERIALS4.1High-Resolution Gas Chromatograph/High-Resolution Mass Spectrometer/Data System (HRGC/HRMS/DS) - The GC must be equipped for temperature programming, and all required accessories must be available, such as syringes, gases, and capillary columns.4.1.1GC Injection Port - The GC injection port must be designed forcapillary columns. The use of splitless injection techniques is recommended. On column 1 µL injections can be used on the 60 m DB-5 column. The use of a moving needle injection port is also acceptable.When using the method described in this protocol, a 2 µL injection volume is used consistently (i.e., the injection volumes for all extracts, blanks, calibration solutions and the performance check samples are 2 µL).One µL injections are allowed; however, laboratories must remainconsistent throughout the analyses by using the same injection volume at all times.4.1.2Gas Chromatograph/Mass Spectrometer (GC/MS) Interface - TheoGC/MS interface components should withstand 350C. The interface must be designed so that the separation of 2,3,7,8-TCDD from the other TCDD isomers achieved in the gas chromatographic column is not appreciably degraded. Cold spots or active surfaces (adsorption sites) in the GC/MS interface can cause peak tailing and peak broadening. It is recommended that the GC column be fitted directly into the mass spectrometer ion source without being exposed to the ionizing electron beam. Graphite ferrules should be avoided in the injection port because they may adsorbTMthe PCDDs and PCDFs. Vespel, or equivalent, ferrules are recommended.4.1.3Mass Spectrometer - The static resolving power of the instrument must be maintained at a minimum of 10,000 (10 percent valley).4.1.4Data System - A dedicated data system is employed to control the rapid multiple-ion monitoring process and to acquire the data. Quantitation data (peak areas or peak heights) and SIM traces (displays of intensities of each ion signal being monitored including the lock-mass ion as a function of time) must be acquired during the analyses and stored. Quantitations may be reported based upon computer generated peak areas or upon measured peak heights (chart recording). The data system must be capable of acquiring data at a minimum of 10 ions in a single scan. It is also recommended to have a data system capable of switching to different sets of ions (descriptors) at specified times during an HRGC/HRMS acquisition. The data system should be able to provide hard copies of individual ion chromatograms for selected gas chromatographic time intervals. It should also be able to acquire mass spectral peak profiles (Sec. 8.1.2.3) and provide hard copies of peak profiles to demonstrate the required resolving power. The data system should permit the measurement of noise on the base line.NOTE:The detector ADC zero setting must allow peak-to-peak measure-ment of the noise on the base line of every monitored channeland allow for good estimation of the instrument resolvingpower. In Figure 2, the effect of different zero settings onthe measured resolving power is shown.4.2GC Columns4.2.1In order to have an isomer specific determination for 2,3,7,8-TCDD and to allow the detection of OCDD/OCDF within a reasonable time interval in one HRGC/HRMS analysis, use of the 60 m DB-5 fused silica capillary column is recommended. Minimum acceptance criteria must be demonstrated and documented (Sec. 8.2.2). At the beginning of each 12 hour period (after mass resolution and GC resolution are demonstrated) during which sample extracts or concentration calibration solutions will be analyzed, column operating conditions must be attained for the required separation on the column to be used for samples. Operating conditions known to produce acceptable results with the recommended column are shown in Sec. 7.6.4.2.2Isomer specificity for all 2,3,7,8-substituted PCDDs/PCDFscannot be achieved on the 60 m DB-5 GC column alone. In order to determine the proper concentrations of the individual 2,3,7,8-substituted congeners, the sample extract must be reanalyzed on another GC column that resolves the isomers.4.2.330 m DB-225 fused silica capillary column, (J&W Scientific) orequivalent.4.3Miscellaneous Equipment and Materials - The following list of items does not necessarily constitute an exhaustive compendium of the equipment needed for this analytical method.4.3.1Nitrogen evaporation apparatus with variable flow rate.4.3.2Balances capable of accurately weighing to 0.01 g and0.0001 g.4.3.3Centrifuge.4.3.4Water bath, equipped with concentric ring covers and capableoof being temperature controlled within + 2C.4.3.5Stainless steel or glass container large enough to holdcontents of one pint sample containers.4.3.6Glove box.4.3.7Drying oven.4.3.8Stainless steel spoons and spatulas.4.3.9Laboratory hoods.4.3.10Pipets, disposable, Pasteur, 150 mm long x 5 mm ID.4.3.11Pipets, disposable, serological, 10 mL, for thepreparation of the carbon columns specified in Sec. 7.5.3.4.3.12Reaction vial, 2 mL, silanized amber glass (Reacti-vial,or equivalent).4.3.13Stainless steel meat grinder with a 3 to 5 mm hole sizeinner plate.4.3.14Separatory funnels, 125 mL and 2000 mL.4.3.15Kuderna-Danish concentrator, 500 mL, fitted with 10 mLconcentrator tube and three ball Snyder column.TM4.3.16Teflon or carborundum (silicon carbide) boiling chips(or equivalent), washed with hexane before use.TMNOTE:Teflon boiling chips may float in methylene chloride, may not work in the presence of any water phase, and may be penetratedby nonpolar organic compounds.4.3.17Chromatographic columns, glass, 300 mm x 10.5 mm, fittedTMwith Teflon stopcock.4.3.18Adapters for concentrator tubes.4.3.19Glass fiber filters, 0.70 µm, Whatman GFF, or equivalent.4.3.20Dean-Stark trap, 5 or 10 mL, with T-joints, condenser and 125 mL flask.4.3.21Continuous liquid-liquid extractor.4.3.22All glass Soxhlet apparatus, 500 mL flask.4.3.23Soxhlet/Dean Stark extractor (optional), all glass, 500 mL flask.4.3.24Glass funnels, sized to hold 170 mL of liquid.4.3.25Desiccator.4.3.26Solvent reservoir (125 mL), Kontes; 12.35 cm diameter (special order item), compatible with gravity carbon column.4.3.27Rotary evaporator with a temperature controlled water bath.4.3.28High speed tissue homogenizer, equipped with an EN-8 probe, or equivalent.4.3.29Glass wool, extracted with methylene chloride, dried and stored in a clean glass jar.4.3.30Extraction jars, glass, 250 mL, with teflon lined screw cap.4.3.31Volumetric flasks, Class A - 10 mL to 1000 mL.4.3.32Glass vials, 1 dram (or metric equivalent).NOTE:Reuse of glassware should be minimized to avoid the risk of contamination. All glassware that is reused must bescrupulously cleaned as soon as possible after use, accordingto the following procedure: Rinse glassware with the lastsolvent used in it. Wash with hot detergent water, then rinsewith copious amounts of tap water and several portions oforganic-free reagent water. Rinse with high purity acetoneand hexane and store it inverted or capped with solvent rinsedaluminum foil in a clean environment.5.0REAGENTS AND STANDARD SOLUTIONS5.1Organic-free reagent water - All references to water in this method refer to organic-free reagent water, as defined in Chapter One.5.2Column Chromatography Reagents5.2.1Alumina, neutral, 80/200 mesh (Super 1, Woelm®, orequivalent). Store in a sealed container at room temperature, in a desiccator, over self-indicating silica gel.5.2.2Alumina, acidic AG4, (Bio Rad Laboratories catalog #132-1240,or equivalent). Soxhlet extract with methylene chloride for 24 hours if blanks show contamination, and activate by heating in a foil covered glassocontainer for 24 hours at 190C. Store in a glass bottle sealed with a TMTeflon lined screw cap.5.2.3Silica gel, high purity grade, type 60, 70-230 mesh; Soxhletextract with methylene chloride for 24 hours if blanks show contamination, and activate by heating in a foil covered glass container for 24 hours at o TM190C. Store in a glass bottle sealed with a Teflon lined screw cap.5.2.4Silica gel impregnated with sodium hydroxide. Add one part(by weight) of 1 M NaOH solution to two parts (by weight) silica gel (extracted and activated) in a screw cap bottle and mix with a glass rodTM until free of lumps. Store in a glass bottle sealed with a Teflon lined screw cap.5.2.5Silica gel impregnated with 40 percent (by weight) sulfuricacid. Add two parts (by weight) concentrated sulfuric acid to three parts (by weight) silica gel (extracted and activated), mix with a glass rod until free of lumps, and store in a screw capped glass bottle. Store inTMa glass bottle sealed with a Teflon lined screw cap.5.2.6Celite 545® (Supelco), or equivalent.5.2.7Active carbon AX-21 (Anderson Development Co., Adrian, MI), oro equivalent, prewashed with methanol and dried in vacuo at 110C. Store inTMa glass bottle sealed with a Teflon lined screw cap.5.3Reagents5.3.1Sulfuric acid, H SO, concentrated, ACS grade, specific gravity241.84.5.3.2Potassium hydroxide, KOH, ACS grade, 20 percent (w/v) inorganic-free reagent water.5.3.3Sodium chloride, NaCl, analytical reagent, 5 percent (w/v) inorganic-free reagent water.5.3.4Potassium carbonate, K CO, anhydrous, analytical reagent.235.4Desiccating agent5.4.1Sodium sulfate (powder, anhydrous), Na SO. Purify by heating24oat 400C for 4 hours in a shallow tray, or by precleaning the sodium sulfate with methylene chloride. If the sodium sulfate is precleaned with methylene chloride, a method blank must be analyzed, demonstrating that there is no interference from the sodium sulfate.5.5Solvents5.5.1Methylene chloride, CH Cl. High purity, distilled in glass22or highest available purity.5.5.2Hexane, C H. High purity, distilled in glass or highest614available purity.5.5.3Methanol, CH OH. High purity, distilled in glass or highest3available purity.5.5.4Nonane, C H. High purity, distilled in glass or highest920available purity.5.5.5Toluene, C H CH. High purity, distilled in glass or highest653available purity.5.5.6Cyclohexane, C H. High purity, distilled in glass or highest612available purity.5.5.7Acetone, CH C0CH. High purity, distilled in glass or highest33available purity.5.6High-Resolution Concentration Calibration Solutions (Table 5) - Five nonane solutions containing unlabeled (totaling 17) and carbon-labeled (totaling 11) PCDDs and PCDFs at known concentrations are used to calibrate the instrument. The concentration ranges are homologue dependent, with the lowest values for the tetrachlorinated dioxin and furan (1.0 pg/µL) and the highest values for the octachlorinated congeners (1000 pg/µL).5.6.1Depending on the availability of materials, these high-resolution concentration calibration solutions may be obtained from the Environmental Monitoring Systems Laboratory, U.S. EPA, Cincinnati, Ohio.However, additional secondary standards must be obtained from commercial sources, and solutions should be prepared in the analyst's laboratory. It is the responsibility of the laboratory to ascertain that the calibration solutions received (or prepared) are indeed at the appropriate concentrations before they are used to analyze samples.5.6.2Store the concentration calibration solutions in 1 mLminivials at room temperature in the dark.5.7GC Column Performance Check Solution - This solution contains the first and last eluting isomers for each homologous series from tetra- through heptachlorinated congeners. The solution also contains a series of other TCDD isomers for the purpose of documenting the chromatographic resolution. The C -2,3,7,8-TCDD is also present. The laboratory is required to use nonane as 1312the solvent and adjust the volume so that the final concentration does not exceed 100 pg/µL per congener. Table 7 summarizes the qualitative composition (minimum requirement) of this performance evaluation solution.5.8Sample Fortification Solution - This nonane solution contains the nine internal standards at the nominal concentrations that are listed in Table 2.The solution contains at least one carbon-labeled standard for each homologous series, and it is used to measure the concentrations of the native substances.(Note that C -OCDF is not present in the solution.)13125.9Recovery Standard Solution - This nonane solution contains tworecovery standards, C -1,2,3,4-TCDD and C -1,2,3,7,8,9-HxCDD, at a nominal13131212concentration of 50 pg/µL per compound. 10 to 50 µL of this solution will be spiked into each sample extract before the final concentration step and HRGC/HRMS analysis.5.10Matrix Spike Fortification Solution - Solution used to prepare the MS and MSD samples. It contains all unlabeled analytes listed in Table 5 at con-centrations corresponding to the HRCC 3.6.0SAMPLE COLLECTION, PRESERVATION, AND HANDLING6.1See the introductory material to this chapter, Organic Analytes,Sec. 4.1.6.2Sample Collection6.2.1Sample collection personnel should, to the extent possible,homogenize samples in the field before filling the sample containers.This should minimize or eliminate the necessity for sample homogenization in the laboratory. The analyst should make a judgment, based on the appearance of the sample, regarding the necessity for additional mixing.If the sample is clearly not homogeneous, the entire contents should be transferred to a glass or stainless steel pan for mixing with a stainless steel spoon or spatula before removal of a sample portion for analysis.6.2.2Grab and composite samples must be collected in glasscontainers. Conventional sampling practices must be followed. The bottle must not be prewashed with sample before collection. Sampling equipment must be free of potential sources of contamination.6.3Grinding or Blending of Fish Samples - If not otherwise specified by the U.S. EPA, the whole fish (frozen) should be blended or ground to provide a homogeneous sample. The use of a stainless steel meat grinder with a 3 to 5 mmhole size inner plate is recommended. In some circumstances, analysis of fillet or specific organs of fish may be requested by the U.S. EPA. If so requested, the above whole fish requirement is superseded.6.4Storage and Holding Times - All samples, except fish and adiposeotissue samples, must be stored at 4C in the dark, extracted within 30 days and completely analyzed within 45 days of extraction. Fish and adipose tissueosamples must be stored at -20C in the dark,extracted within 30 days and completely analyzed within 45 days of collection. Whenever samples are analyzed after the holding time expiration date, the results should be considered to be minimum concentrations and should be identified as such.NOTE:The holding times listed in Sec. 6.4 are recommendations. PCDDs and PCDFs are very stable in a variety of matrices, and holding timesunder the conditions listed in Sec. 6.4 may be as high as a year forcertain matrices. Sample extracts, however, should always beanalyzed within 45 days of extraction.6.5Phase Separation - This is a guideline for phase separation for very wet (>25 percent water) soil, sediment and paper pulp samples. Place a 50 g portion in a suitable centrifuge bottle and centrifuge for 30 minutes at 2,000 rpm. Remove the bottle and mark the interface level on the bottle. Estimate the relative volume of each phase. With a disposable pipet, transfer the liquid layer into a clean bottle. Mix the solid with a stainless steel spatula and remove a portion to be weighed and analyzed (percent dry weight determination, extraction). Return the remaining solid portion to the original sample bottle (empty) or to a clean sample bottle that is properly labeled, and store it as appropriate. Analyze the solid phase by using only the soil, sediment and paper pulp method. Take note of, and report, the estimated volume of liquid before disposing of the liquid as a liquid waste.6.6Soil, Sediment, or Paper Sludge (Pulp) Percent Dry Weight Determination - The percent dry weight of soil, sediment or paper pulp samples showing detectable levels (see note below) of at least one 2,3,7,8-substituted PCDD/PCDF congener is determined according to the following procedure. Weigh a 10 g portion of the soil or sediment sample (+ 0.5 g) to three significantofigures. Dry it to constant weight at 110C in an adequately ventilated oven. Allow the sample to cool in a desiccator. Weigh the dried solid to three significant figures. Calculate and report the percent dry weight. Do not use this solid portion of the sample for extraction, but instead dispose of it as hazardous waste.NOTE:Until detection limits have been established (Sec. 1.3), the lower MCLs (Table 1) may be used to estimate the minimum detectablelevels.% dry weight = g of dry sample x 100g of sampleCAUTION:Finely divided soils and sediments contaminated with PCDDs/PCDFs are hazardous because of the potential forinhalation or ingestion of particles containing PCDDs/PCDFs(including 2,3,7,8-TCDD). Such samples should be handled ina confined environment (i.e., a closed hood or a glove box).6.7Lipid Content Determination6.7.1Fish Tissue - To determine the lipid content of fish tissue,concentrate 125 mL of the fish tissue extract (Sec. 7.2.2), in a tared 200mL round bottom flask, on a rotary evaporator until a constant weight (W)is achieved.100 (W) Percent lipid =10Dispose of the lipid residue as a hazardous waste if the results ofthe analysis indicate the presence of PCDDs or PCDFs.6.7.2Adipose Tissue - Details for the determination of the adiposetissue lipid content are provided in Sec. 7.3.3.7.0PROCEDURE7.1Internal standard addition7.1.1Use a portion of 1 g to 1000 g (+ 5 percent) of the sample tobe analyzed. Typical sample size requirements for different matrices are given in Sec. 7.4 and in Table 1. Transfer the sample portion to a tared flask and determine its weight.7.1.2Except for adipose tissue, add an appropriate quantity of thesample fortification mixture (Sec. 5.8) to the sample. All samples should be spiked with 100 µL of the sample fortification mixture to give internal standard concentrations as indicated in Table 1. As an example, for C -13122,3,7,8-TCDD, a 10 g soil sample requires the addition of 1000 pg of C -13122,3,7,8-TCDD to give the required 100 ppt fortification level. The fish tissue sample (20 g) must be spiked with 200 µL of the internal standard solution, because half of the extract will be used to determine the lipid content (Sec. 6.7.1).7.1.2.1For the fortification of soil, sediment, fly ash,water, fish tissue, paper pulp and wet sludge samples, mix thesample fortification solution with 1.0 mL acetone.7.1.2.2Do not dilute the nonane solution for the othermatrices.7.1.2.3The fortification of adipose tissue is carried outat the time of homogenization (Sec. 7.3.2.3).7.2Extraction and Purification of Fish and Paper Pulp Samples7.2.1Add 60 g anhydrous sodium sulfate to a 20 g portion of ahomogeneous fish sample (Sec. 6.3) and mix thoroughly with a stainless。