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METHOD 8325
SOLVENT EXTRACTABLE NONVOLATILE COMPOUNDS BY
HIGH PERFORMANCE LIQUID CHROMATOGRAPHY/PARTICLE BEAM/MASS
SPECTROMETRY (HPLC/PB/MS)
1.0
SCOPE AND APPLICATION
1.1This method describes the use of high performance liquid chromatography (HPLC),coupled with particle beam (PB) mass spectrometry (MS), for the determination of benzidines and nitrogen-containing pesticides in water and wastewater. The following compounds can be determined by this method:
Compound
CAS No.a Benzidine
92-87-5Benzoylprop ethyl 33878-50-1
Carbaryl
63-25-2o-Chlorophenyl thiourea 5344-82-13,3'-Dichlorobenzidine 91-94-13,3'-Dimethoxybenzidine 119-90-43,3'-Dimethylbenzidine 612-82-8Diuron
330-54-1Linuron (Lorox)330-55-2Monuron 150-68-5Rotenone 83-79-4Siduron
1982-49-6
Chemical Abstract Service Registry Number
a
1.2The method also may be appropriate for the analysis of benzidines and nitrogen-containing pesticides in non-aqueous matrices. The method may be applicable to other compounds that can be extracted from a sample with methylene chloride and are amenable to separation on a reverse phase liquid chromatography column and transferable to the mass spectrometer with a particle beam interface.
1.3Preliminary investigation indicates that the following compounds also may be amenable to this method: Aldicarb sulfone, Carbofuran, Methiocarb, Methomyl (Lannate), Mexacarbate (Zectran), and N-(1-Naphthyl)thiourea. Ethylene thiourea and o-Chlorophenyl thiourea have been successfully analyzed by HPLC/PB/MS, but have not been successfully extracted from a water matrix.
1.4Tables 4 - 6 present method detection limits (MDLs) for the target compounds, ranging from 2 to 25 μg/L. The MDLs are compound- and matrix-dependent.
1.5This method is restricted to use by, or under the supervision of, analysts experienced in the use of HPLC and skilled in the interpretation of particle beam mass spectrometry. Each analyst must demonstrate the ability to generate acceptable results with this method.
2.0SUMMARY OF METHOD
2.1The target compounds for this method must be extracted from the sample matrix prior to analysis.
2.1.1Benzidines and nitrogen-containing pesticides are extracted from aqueous
matrices at a neutral pH with methylene chloride, using a separatory funnel (Method 3510), a continuous liquid-liquid extractor (Method 3520), or other suitable technique.
2.1.2Solid samples are extracted using Methods 3540 (Soxhlet), 3541 (Automated
Soxhlet), 3550 (Ultrasonic extraction), or other suitable technique.
2.2An aliquot of the sample extract is introduced into the HPLC instrument and a gradient elution program is used to chromatographically separate the target analytes, using reverse-phase liquid chromatography.
2.3Once separated, the analytes are transferred to the mass spectrometer via a particle beam HPLC/MS interface. Quantitation is performed using an external standard approach.
2.4An optional internal standard quantitation procedure is included for samples which contain coeluting compounds or where matrix interferences preclude the use of the external standard procedure.
2.5The use of ultraviolet/visible (UV/VIS) detection is an appropriate option for the analysis of routine samples, whose general composition has been previously determined.
3.0INTERFERENCES
3.1Refer to Methods 3500 and 8000 for general discussions of interferences with the sample extraction and chromatographic separation procedures.
3.2Although this method relies on mass spectrometric detection, which can distinguish between chromatographically co-eluting compounds on the basis of their masses, co-elution of two or more compounds will adversely affect method performance. When two compounds coelute, the transport efficiency of both compounds through the particle beam interface generally improves, and the ion abundances observed in the mass spectrometer increase. The degree of signal enhancement by coelution is compound-dependent.
3.2.1This coelution effect invalidates the calibration curve and, if not recognized, will
result in incorrect quantitative measurements. Procedures are given in this method to check for co-eluting compounds, and must be followed to preclude inaccurate measurements.
3.2.2An optional internal standard calibration procedure has been included for use in
instances of severe co-elution or matrix interferences.
3.3 A major source of potential contamination is HPLC columns which may contain silicon compounds and other contaminants that could prevent the determination of method analytes. Generally, contaminants will be leached from the columns into mobile phase and produce a variable background. Figure 1 shows unacceptable background contamination from a column with stationary phase bleed.
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3.4Contamination may occur when a sample containing low analyte concentrations is analyzed immediately after a sample containing relatively high analyte concentrations. After analysis of a sample containing high analyte concentrations, one or more method blanks should be analyzed.Normally, with HPLC, this is not a problem unless the sample concentrations are at the percent level.
4.0
APPARATUS AND MATERIALS
4.1High performance liquid chromatograph (HPLC) - An analytical system with programmable solvent delivery system and all necessary accessories including 5 μL injection loop,analytical columns, purging gases, etc. The solvent delivery system must be capable, at a minimum,of handling a binary solvent system, and must be able to accurately deliver flow rates between 0.20- 0.40 mL/min. Pulse dampening is recommended, but not required. The chromatographic system must be able to be interfaced with a mass spectrometer (MS). An autoinjector is recommended and should be capable of accurately delivering 1 - 10 μL injections without affecting the chromatography.
4.1.1HPLC Columns - An analytical column is needed, and a guard column is highly recommended.
4.1.1.1Analytical Column - Reverse phase column, C chemically bonded to
184-10 μm silica particles, 150 - 200 mm x 2 mm, (Waters C-18 Novapak or equivalent).Residual acidic sites should be blocked (endcapped) with methyl or other non-polar groups and the stationary phase must be bonded to the solid support to minimize column bleed. Select a column that exhibits minimal bleeding. New columns must be conditioned overnight before use by pumping a 75 - 100% v/v acetonitrile:water solution through the column at a rate of about 0.05 mL/min. Other packings and column sizes may be used if appropriate performance can be achieved.
4.1.1.2
Guard Column - Packing similar to that used in analytical column.
4.1.2HPLC/MS interface - The particle beam HPLC/MS interface must reduce the ion source pressure to a level compatible with the generation of classical electron ionization (EI)
mass spectra, i.e., about 1 x 10 - 1 x 10
Torr, while delivering sufficient quantities of analytes -4 -6to the conventional EI source to meet sensitivity, accuracy, and precision requirements. The concentrations of background components with masses greater than 62 Daltons should be reduced to levels that do not produce ions greater than a relative abundance of 10% in the mass spectra of the analytes.
4.2Mass spectrometer system - The mass spectrometer must be capable of electron ionization at a nominal electron energy of 70 eV. The spectrometer should be capable of scanning from 45 to 500 amu in 1.5 seconds or less (including scan overhead). The spectrometer should produce a mass spectrum that meets the criteria in Table 1 when 500 ng or less of DFTPPO are introduced into the HPLC.
4.3Data system - A computer system must be interfaced to the mass spectrometer, and must be capable of the continuous acquisition and storage on machine-readable media of all mass spectra obtained throughout the duration of the chromatographic program. The computer software must be capable of searching any HPLC/MS data file for ions of a specified mass and plotting such abundance data versus time or scan number.
4.4
Volumetric flasks - Class A, in various sizes, for preparation of standards.
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4.5Vials - 10-mL amber glass vials with polytetrafluororethylene (PTFE)-lined screw caps or crimp tops.
4.6 Analytical balance - capable of weighing 0.0001 g.4.7
Extract filtration apparatus 4.7.1
Syringe - 10-mL, with Luer-Lok fitting.
4.7.2Syringe filter assembly, disposable - 0.45 μm pore size PTFE filter in filter assembly with Luer-Lok fitting (Gelman Acrodisc, or equivalent).
5.0
REAGENTS
5.1Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high purity to permit its use without lessening the accuracy of the determination.
5.2Organic-free reagent water - All references to water in this method refer to organic-free reagent water, as defined in Chapter One.
5.3
Solvents - All solvents must be HPLC-grade or equivalent.5.3.1Acetonitrile, CH CN 35.3.2Methanol, CH OH
35.3.3
Ammonium acetate, NH OOCCH , (0.01M in water).
435.4Mobile phase - Two mobile phase solutions are needed, and are designated Solvent A and Solvent B. Degas both solvents in an ultrasonic bath under reduced pressure and maintain by purging with a low flow of helium.
5.4.1Solvent A is a water:acetonitrile solution (75/25, v/v) containing ammonium acetate at a concentration of 0.01M.
5.4.2
Solvent B is 100 % acetonitrile.
5.5Stock standard solutions - Stock solutions may be prepared from pure standard materials or purchased as certified solutions. Commercially-prepared stock standards may be used at any concentration if they are certified by the manufacturer.
5.5.1Prepare stock standard solutions by accurately weighing 0.0100 g of pure material in a volumetric flask. Dilute to known volume in a volumetric flask. If compound purity is certified at 96% or greater, the weight may be used without correction to calculate the concentration of the stock standard. Commercially-prepared stock standards may be used at any concentration if they are certified by the manufacturer or by an independent source.
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5.5.1.1Dissolve benzidines and nitrogen-containing pesticides in methanol,
acetonitrile, or organic-free reagent water.
5.5.1.2Certain analytes, such as 3,3'-dimethoxybenzidine, may require dilution
in 50% (v/v) acetonitrile:water or methanol:water solution.
5.5.1.3Benzidines may be used for calibration purposes in the free base or acid
chlorides forms. However, the concentration of the standard should be calculated as the free base.
5.5.2Transfer the stock standard solutions into amber bottles with PTFE-lined screw-caps or crimp tops. Store at -10E C or less and protect from light. Stock standard solutions should be checked frequently for signs of degradation or evaporation, especially just prior to preparing calibration standards from them.
5.6Surrogate spiking solution - The recommended surrogates are benzidine-D ,8caffeine-N , 3,3'-dichlorobenzidine-D , and bis(perfluorophenyl)-phenylphosphine oxide. Prepare 152 6a solution of the surrogates in methanol or acetonitrile at a concentration of 5 mg/mL of each. Other surrogates may be included in this solution as needed. (A 10-μL aliquot of this solution added to 1L of water gives a concentration of 50 μg/L of each surrogate). Store the surrogate spiking solution in an amber vial in a freezer at -10E C or less.
5.7MS performance check solution - Prepare a 100 ng/μL solution of DFTPPO in acetonitrile.Store this solution in an amber vial in a freezer at -10E C or less.
5.8
Calibration solutions
This method describes two types of calibration procedures that may be applied to the target compounds: external standard calibration, and internal standard calibration. Each procedure requires separate calibration standards. In addition, the performance characteristics of the HPLC/PB/MS system indicate that it may be necessary to employ a second order regression for calibration purposes, unless a very narrow calibration range is chosen. See Method 8000 for additional information on non-linear calibration techniques.
5.8.1For external standard calibration, prepare calibration standards for all target compounds and surrogates in acetonitrile. DFTPPO may be added to one or more calibration solutions to verify MS tune (see Sec. 7.3). Store these solutions in amber vials at -10E C or less. Check these solutions at least quarterly for signs of deterioration.
5.8.2Internal standard calibration requires the use of suitable internal standards (see Method 8000). Ideally, stable, isotopically-labeled, analogs of the target compounds should be used. These labeled compounds are included in the calibration standards and must also be added to each sample extract immediately prior to analysis. Prepare the calibration standards in a fashion similar to that for external standard calibration, but include each internal standard in each of the calibration standards.
The concentration of the internal standards should be 50 - 100 times the lowest concentration of the unlabeled target compounds. In addition, the concentration of the internal standards does not vary with the concentrations of the target compounds, but is held constant.Store these solutions in amber vials at -10E C or less. Check these solutions at least quarterly for signs of deterioration.
5.9Internal standard spiking solution - This solution is required when internal standard quantitation is used. Prepare a solution containing each of the internal standards that will be used for quantitation of target compounds (see Sec. 5.8.2) in methanol. The concentration of this solution must be such that a 1-μL volume of the spiking solution added to a 1-mL final extract will result in a concentration of each internal standard that is equal to the concentration of the internal standard in the calibration standards in Sec. 5.8.2. Store this solution in an amber vial at -10E C or less. Check this solution at least quarterly for signs of deterioration. This solution is not necessary if only external standard calibration will be used.
5.10Sodium chloride, NaCl - granular, used during sample extraction.
6.0SAMPLE COLLECTION, PRESERVATION, AND HANDLING
6.1See the introductory material to this chapter, Organic Analytes, Sec. 4.1.
6.2Samples should be extracted within 7 days and analyzed within 30 days of extraction. Extracts should be stored in amber vials at -10E C or less.
7.0PROCEDURE
7.1Samples may be extracted by Method 3510 (separatory funnel), Method 3520 (continuous extractor), Method 3535 (solid-phrase extraction), or other appropriate technique. Prior to extraction, add a 10-μL aliquot of the surrogate spiking solution and 100 g of sodium chloride to the sample, and adjust the pH of the sample to 7.0. Samples of other matrices should be extracted by an appropriate sample preparation technique. The concentration of surrogates in the sample should be 20-50 times the method detection limit. Concentrate the extract to 1 mL, and exchange the solvent to methanol, following the procedures in the extraction method.
7.2Establish chromatographic, particle beam interface, and mass spectrometer conditions, using the following conditions as guidance.
Mobile phase purge:Helium at 30 mL/min, continuous
Mobile phase flow rate:0.25 - 0.3 mL/min through the column
Gradient elution:Hold for 1 min at 25% acetonitrile (Solvent A), then
program linearly to about 70% acetonitrile (60%
Solvent B) in 29 min. Start data acquisition
immediately.
Desolvation chamber temperature:45 - 80E C
Ion source temperature:250 - 290E C
Electron energy:70 eV
Scan range:62 to 465 amu, at #1.5 sec/scan NOTE:Post-column addition is an option that improves system precision and, thereby, may improve sensitivity. Post-column flow rates depend on the requirements of
the interface and may range from 0.1 to 0.7 mL/min of acetonitrile. Maintain a
minimum of 30% acetonitrile in the interface.
Analyte-specific chromatographic conditions are also shown in Table 2. (The particle beam interface conditions will depend on the type of nebulizer).
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7.2.1The analyst should follow the manufacturer's recommended conditions for their
interface's optimum performance. The interface is usually optimized during initial installation by flow injection with caffeine or benzidine, and should utilize a mobile phase of acetonitrile/water (50/50, v/v). Major maintenance may require re-optimization.
7.2.2Fine tune the interface by making a series of injections into the HPLC column of
a medium concentration calibration standard and adjusting the operating conditions (Sec. 7.2)
until optimum sensitivity and precision are obtained for the maximum number of target compounds.
7.3Initial calibration
7.3.1Once the operating conditions have been established, calibrate the MS mass and
abundance scales using DFTPPO to meet the recommended criteria in Table 1.
7.3.2Inject a medium concentration standard containing DFTPPO, or separately inject
into the HPLC a 5-μL aliquot of the 100 ng/μL DFTPPO solution and acquire a mass spectrum.
Use HPLC conditions that produce a narrow (at least ten scans per peak) symmetrical peak.
If the spectrum does not meet the criteria (Table 1), the MS ion source must be retuned and adjusted to meet all criteria before proceeding with calibration. An average spectrum across the HPLC peak may be used to evaluate the performance of the system.
Manual (not automated) ion source tuning procedures specified by the manufacturer should be employed during tuning. Mass calibration should be accomplished while an acetonitrile/water (50/50, v/v) mixture is pumped through the HPLC column and the optimized particle beam interface. For optimum long-term stability and precision, interface and ion source parameters should be set near the center of a broad signal plateau rather than at the peak of a sharp maximum (sharp maxima exhibit short-term variations with particle beam interfaces and gradient elution conditions).
7.3.3System performance criteria for the medium concentration standard - Evaluate
the stored HPLC/MS data with the data system software and verify that the HPLC/PB/MS system meets the following performance criteria.
7.3.3.1HPLC performance - 3,3'-dimethylbenzidine and
3,3'-dimethoxybenzidine should be separated by a valley whose height is less than 25%
of the average peak height of these two compounds. If the valley between them exceeds
25%, modify the gradient. If this fails, the HPLC column requires maintenance. See
Sec. 7.4.6.
7.3.3.2Peak tailing - Examine a total ion chromatogram and examine the
degree of peak tailing. Severe tailing indicates a major problem and system
maintenance is required to correct the problem. See Sec. 7.4.6
7.3.3.3MS sensitivity - The signal-to-noise ratio for any compound's spectrum
should be at least 3:1.
7.3.3.4Column bleed - Figure 1 shows an unacceptable chromatogram with
column bleed. Figure 2 shows an acceptable ion chromatogram. Figure 3 is the mass
spectrum of dimethyloctadecyl-silanol, a common stationary phase bleed product. If
unacceptable column bleed is present, the column must be changed or conditioned to
produce an acceptable background.
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7.3.3.5Coeluting compounds - Compounds which coelute cannot be measured
accurately because of carrier effects in the particle beam interface. Peaks must be
examined carefully for coeluting substances and if coeluting compounds are present at
greater than 10% of the concentration of the target compound, either conditions must be
adjusted to resolve the components, or internal standard calibration must be used.
7.3.4Once optimized, the same instrument operating conditions must be used for the
analysis of all calibration standards, samples, blanks, etc.
7.3.5Once all the performance criteria are met, inject a 5-μL aliquot of each of the
other calibration standards using the same HPLC/MS conditions.
7.3.5.1The general method of calibration is a second order regression of
integrated ion abundances of the quantitation ions (Table 3) as a function of amount
injected. For second order regression, a sufficient number of calibration points must be
obtained to accurately determine the equation of the curve. (See Method 8000 for the
appropriate number of standards to be employed for a non-linear calibration). Non-linear
calibration models can be applied to either the external standard or the internal standard
calibration approaches described here.
7.3.5.2For some analytes the instrument response may be linear over a narrow
concentration range. In these instances, an average calibration factor (external
standard) or average response factor (internal standard) may be employed for sample
quantitation (see Method 8000).
7.3.6If a linear calibration model is used, calculate the mean calibration factor or
response factor for each analyte, including the surrogates, as described in Method 8000.
Calculate the standard deviation (SD) and the relative standard deviation (RSD) as well. The RSD of an analyte or surrogate must be less than or equal to 20%, if the linear model is to be applied. Otherwise, proceed as described in Method 8000.
7.4Calibration verification
Prior to sample analysis, verify the MS tune and initial calibration at the beginning of each 8-hour analysis shift using the following procedure:
7.4.1Inject a 5-μL aliquot of the DFTPPO solution or a mid-level calibration standard
containing 500 ng of DFTPPO, and acquire a mass spectrum that includes data for m/z 62-465. If the spectrum does not meet the criteria in Table 1, the MS must be retuned to meet the criteria before proceeding with the continuing calibration check.
7.4.2Inject a 5-μL aliquot of a medium concentration calibration solution and analyze
with the same conditions used during the initial calibration.
7.4.3Demonstrate acceptable performance for the criteria shown in Sec. 7.3.3.
7.4.4Using the initial calibration (either linear or non-linear, external standard or internal
standard), calculate the concentrations in the medium concentration calibration solution and compare the results to the known values in the calibration solution. If calculated concentrations deviate by more than 20% from known values, adjust the instrument and inject the standard again. If the calibration cannot be verified with the second injection, then a new CD-ROM8325 - 8Revision 0
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initial calibration must be performed after taking corrective actions such as those described in Sec. 7.9.
7.5Sample Analysis
7.5.1The column should be conditioned overnight before each use by pumping a
acetonitrile:water (70% v/v) solution through it at a rate of about 0.05 mL/min.
7.5.2Filter the extract through a 0.45 μm filter. If internal standard calibration is
employed, add 10 μL of the internal standard spiking solution to the 1-mL final extract immediately before injection.
7.5.3Analyze a 5-μL aliquot of the extract, using the operating conditions established
in Secs. 7.2 and 7.3.
7.6Qualitative identification
The qualitative identification of compounds determined by this method is based on retention time and on comparison of the sample mass spectrum, after background correction, with characteristic ions in a reference mass spectrum. The reference mass spectrum must be generated by the laboratory using the conditions of this method. The characteristic ions from the reference mass spectrum are defined as the three ions of greatest relative intensity, or any ions over 30% relative intensity, if less than three such ions occur in the reference spectrum. Compounds are identified when the following criteria are met.
7.6.1The intensities of the characteristic ions of a compound must maximize in the
same scan or within one scan of each other. Selection of a peak by a data system target compound search routine where the search is based on the presence of a target chromatographic peak containing ions specific for the target compound at a compound-specific retention time will be accepted as meeting this criterion.
7.6.2The retention time of the sample component is within ± 10% of the retention time
of the standard.
7.6.3The relative intensities of the characteristic ions agree within 20% of the relative
intensities of these ions in the reference spectrum. (Example: For an ion with an abundance of 50% in the reference spectrum, the corresponding abundance in a sample spectrum can range between 30% and 70%.)
7.6.4Structural isomers that produce very similar mass spectra should be identified as
individual isomers if they have sufficiently different HPLC retention times. Sufficient GC resolution is achieved if the height of the valley between two isomer peaks is less than 25% of the sum of the two peak heights. Otherwise, structural isomers are identified as isomeric pairs.
7.6.5Identification is hampered when sample components are not resolved
chromatographically and produce mass spectra containing ions contributed by more than one analyte. When HPLC peaks obviously represent more than one sample component (i.e., a broadened peak with shoulder(s) or a valley between two or more maxima), appropriate selection of analyte spectra and background spectra is important.
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7.6.6Examination of extracted ion current profiles of appropriate ions can aid in the
selection of spectra, and in qualitative identification of compounds. When analytes coelute
(i.e., only one chromatographic peak is apparent), the identification criteria may be met, but
each analyte spectrum will contain extraneous ions contributed by the coeluting compound.
7.7Quantitative Analysis
7.7.1Complete chromatographic resolution is necessary for accurate and precise
measurements of analyte concentrations. Compounds which coelute cannot be measured accurately because of carrier effects in the particle beam interface. Peaks must be examined carefully for coeluting substances and if coeluting compounds are present at greater than 10% of the concentration of the target compound, either conditions must be adjusted to resolve the components, or the results for the target compound must be flagged as potentially positively biased.
7.7.2Calculate the concentration of each analyte, using either the external standard
or internal standard calibration. See Method 8000 for the specific equations to be employed for either the non-linear or linear calibration models.
7.7.3If the response for any quantitation ion exceeds the initial calibration range of the
HPLC/PB/MS system, the sample extract must be diluted and reanalyzed. When internal standard calibration is employed, additional internal standard must be added to the diluted extract to maintain the same concentration as in the calibration standards.
7.8HPLC-UV/VIS Detection (optional)
7.8.1Prepare calibration solutions as outlined in Sec. 5.8.
7.8.2Inject 5 μL of each calibration solution onto the HPLC, using the chromatographic
conditions outlined in Secs. 7.2.1 and 7.2.2. Integrate the area under the full chromatographic peak at the optimum wavelength (or at 230 nm if that option is not available) for each target compound at each concentration.
7.8.3The retention time of the chromatographic peak is an important criterion for
analyte identification. Therefore, the ratio of the retention time of the sample analyte to the standard analyte should be 1.0 ± 0.1.
7.8.4Calculate calibration factors or response factors as described in Method 8000,
for either external standard or internal standard calibration, and evaluate the calibration linearity as described in Method 8000.
7.8.5Verify the calibration at the beginning of each 8-hour analytical shift, as described
above.
7.8.6Once the calibration has been verified, inject a 5-μL aliquot of the sample extract,
start the HPLC gradient elution, load and inject the sample aliquot, and begin data acquisition.
Refer to Method 8000 for guidance on calculation of concentration.
7.9Corrective Actions
When the initial calibration cannot be verified, one or more of the following corrective actions may be necessary.
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7.9.1Major maintenance such as cleaning an ion source, cleaning the entrance lens,
quadrapole rods, etc., will require a new initial calibration.
7.9.2Check and adjust HPLC and/or MS operating conditions; check the MS resolution,
and calibrate the mass scale.
7.9.3Replace the mobile phases with fresh solvents. Verify that the flow rate from the
HPLC pump is constant.
7.9.4Flush the HPLC column with acetonitrile.
7.9.5Replace the HPLC column. This action will cause a change in retention times.
7.9.6Prepare fresh calibration solutions, and repeat the initial calibration step.
7.9.7Replace any components that leak.
7.9.8Replace the MS electron multiplier, or any other faulty components.
7.9.9Clean the interface to eliminate plugged components and/or replace skimmers
according to the manufacturer's instructions.
7.9.10If peak areas are determined by the instrument software, verify values by manual
integration.
7.9.11Increasing ion source temperature can reduce peak tailing, but excessive ion
source temperature can affect the quality of the spectra for some compounds.
7.9.12Air leaks into the interface may effect the quality of the spectra (e.g., DFTPPO),
especially when the ion source is operated at temperatures in excess of 280E C.
8.0QUALITY CONTROL
8.1Refer to Chapter One and Method 8000 for specific quality control (QC) procedures. Quailty control procedures to ensure the proper operation of the various sample preparation techniques can be found in Method 3500. Each laboratory should maintain a formal quality assurance program. The laboratory should also maintain records to document the quality of the data generated.
8.2Quality control procedures necessary to evaluate the HPLC system operation are found in Method 8000, Sec. 7.0 and includes evaluation of retention time windows, calibration verification and chromatographic analysis of samples. Necessary instrument QC is found in the following sections.
8.2.1The HPLC/PB/MS system should be tuned to meet the DFTPPO criteria in Secs.
7.3.1 and 7.4.1.
8.2.2There should be an initial calibration of the HPLC/PB/MS system as described
in Sec. 7.3.
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8.2.3The HPLC/PB/MS system should meet the system performance criteria in Sec.
7.3.3, each 8 hours.
8.3Initial Demonstration of Proficiency - Each laboratory must demonstrate initial proficiency with each sample preparation and determinative method combination it utilizes, by generating data of acceptable accuracy and precision for target analytes in a clean matrix. The laboratory must also repeat the following operations whenever new staff are trained or significant changes in instrumentation are made. See Method 8000, Sec. 8.0 for information on how to accomplish this demonstration.
8.4Sample Quality Control for Preparation and Analysis - The laboratory must also have procedures for documenting the effect of the matrix on method performance (precision, accuracy, and detection limit). At a minimum, this includes the analysis of QC samples including a method blank, a matrix spike, a duplicate, and a laboratory control sample (LCS) in each analytical batch and the addition of surrogates to each field sample and QC sample.
8.4.1Documenting the effect of the matrix should include the analysis of at least one
matrix spike and one duplicate unspiked sample or one matrix spike/matrix spike duplicate pair.
The decision on whether to prepare and analyze duplicate samples or a matrix spike/matrix spike duplicate must be based on a knowledge of the samples in the sample batch. If samples are expected to contain target analytes, then laboratories may use one matrix spike and a duplicate analysis of an unspiked field sample. If samples are not expected to contain target analytes, laboratories should use a matrix spike and matrix spike duplicate pair.
8.4.2 A Laboratory Control Sample (LCS) should be included with each analytical batch.
The LCS consists of an aliquot of a clean (control) matrix similar to the sample matrix and of the same weight or volume. The LCS is spiked with the same analytes at the same concentrations as the matrix spike. When the results of the matrix spike analysis indicate a potential problem due to the sample matrix itself, the LCS results are used to verify that the laboratory can perform the analysis in a clean matrix.
8.4.3See Method 8000, Sec. 8.0 for the details on carrying out sample quality control
procedures for preparation and analysis.
8.5Surrogate recoveries - The laboratory must evaluate surrogate recovery data from individual samples versus the surrogate control limits developed by the laboratory. See Method 8000, Sec. 8.0 for information on evaluating surrogate data and developing and updating surrogate limits.
8.6It is recommended that the laboratory adopt additional quality assurance practices for use with this method. The specific practices that are most productive depend upon the needs of the laboratory and the nature of the samples. Whenever possible, the laboratory should analyze standard reference materials and participate in relevant performance evaluation studies.
9.0METHOD PERFORMANCE
9.1Single laboratory accuracy and precision data for the benzidines and nitrogen-containing pesticides are presented in Tables 4 - 6. Five to seven 1-L aliquots of organic-free reagent water, containing approximately five times the MDL of each analyte, were analyzed with this procedure (Reference 1). The final extract volume was 0.5 mL for these determinations.
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9.1.1Method detection limits (MDLs) are presented in Tables 4 - 6.
9.1.2 A multi-laboratory (12 laboratories) validation of the determinative step was done
for four of the analytes (benzidine, 3,3'-dimethoxybenzidine, 3,3'-dimethylbenzidine, 3,3'-dichlorobenzidine). Table 7 provides the results from this study for single laboratory precision, overall laboratory precision, and overall laboratory accuracy. The two concentration levels shown represent the two extremes of the concentration range studied.
10.0REFERENCES
1.Bellar, T.A., Behymer, T.D., Ho, J.S., Budde, W.L., "Method 553: Determination of Benzidines
and Nitrogen-Containing Pesticides in Water by Liquid-Liquid Extraction or Liquid-Solid Extraction and Reverse Phase High Performance Liquid Chromatography/Particle Beam/Mass Spectrometry", U.S. Environmental Protection Agency, EMSL-Cincinnati, Revision 1.1, August 1992.
2.Bellar, T.A., Behymer, T.D., Budde, W.L., "Investigation of Enhanced Ion Abundances from
a Carrier Process in High-Performance Liquid Chromatography Particle Beam Mass
Spectrometry", J. Am. Soc. Mass Spectrom., 1990, 1, 92-98.
3.Behymer, T.D., Bellar, T.A., and Budde, W.L., "Liquid Chromatography/Particle Beam/Mass
Spectrometry of Polar Compounds of Environmental Interest", Anal. Chem., 1990, 62, 1686-1690.
4.Ho, J.S., Behymer, T.D., Budde, W.L., and Bellar, T.A., "Mass Transport and Calibration in
Liquid Chromatography/ Particle Beam/ Mass Spectrometry", J. Am. Soc. Mass Spectrom., 1992, 3, 662-671.
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ION ABUNDANCE CRITERIA FOR BIS(PERFLUOROPHENYL)PHENYLPHOSPHINE
(DECAFLUOROTRIPHENYLPHOSPHINE OXIDE, DFTPPO)
m/z Relative Abundance Purpose of Specification 1
77Present, major ion Low mass sensitivity 168Present, major ion Mid-mass sensitivity
169 4 - 10% of 168Mid-mass resolution and isotope ratio 271Present, major ion Base peak
365 5 - 10% of base peak Baseline threshold check
438Present Important high mass fragment 458Present
Molecular ion
459
15 - 24% of mass 458
High mass resolution and isotope ratio
The primary use of all the ions is to check the mass calibration of the mass spectrometer.1
The second use of these ions are the mass resolution checks, including the natural isotope abundance ratios. The correct setting of the baseline threshold is indicated by the presence of low intensity ions, and is the third use of this test. Finally, the ion abundance ranges may provide some standardization to fragmentation patterns of the target compounds.
TABLE 2
RECOMMENDED HPLC CHROMATOGRAPHIC CONDITIONS FOR BENZIDINES AND NITROGEN-CONTAINING PESTICIDES
Initial Mobile Initial Gradient Final Mobile Phase (v/v %)Time (min)Time Phase (v/v %)
75/25
129
30/70
(water /CH CN)
(water /CH CN)
1133 Water contains 0.01M ammonium acetate.
1
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RETENTION TIME DATA AND QUANTITATION IONS FOR TARGET COMPOUNDS
Retention Retention Time Time
Quantitation
Compound
System 1System 2Ion
a
b
Benzidine
4.3 4.9184Benzoylprop ethyl 24.831.3105Caffeine 1.4 1.6194Carbaryl
10.114.7144O-Chlorophenyl thiourea 2.7 3.01513,3'-Dichlorobenzidine 16.622.72523,3'-Dimethoxybenzidine 8.111.52443,3'-Dimethylbenzidine 8.512.4212Diuron
11.016.172Ethylene thiourea 1.2 1.4102Linuron 16.021.9161Rotenone 21.127.4192Siduron 14.8
20.6
93
Surrogates:c
Benzidine-d 4.2 4.81928Caffeine-N 1.3 1.6196152
3,3'-Dichlorobenzidine-d 16.522.62586Bis(perfluorophenyl)- phenylphosphine oxide
22.0
28.9
271
These retention times were obtained on a Hewlett-Packard 1090 liquid chromatograph with a a Waters C18 Novapak 15 cm x 2 mm column using gradient conditions given in Table 1. These retention times were obtained on a Waters 600 MS liquid chromatograph with a b Waters C18 Novapak 15 cm x 2 mm column using gradient conditions given in Sec. 7.2. These compounds cannot be used as surrogates if their unlabeled analogs are present (see c
Sec. 3.2).
ACCURACY AND PRECISION DATA FROM SIX DETERMINATIONS OF THE TARGET COMPOUNDS IN ORGANIC-FREE REAGENT WATER USING LIQUID-LIQUID EXTRACTION
Mean Mean
True Observed Std.Accuracy
Conc.Conc.Dev.RSD(% of MDL Compound(μg/L)(μg/L)(μg/L)(%)True)(μg/L) Benzidine22.920.50.8 3.389.6 2.5 Benzoylprop ethyl32.533.0 1.1 3.3101.6 3.7 Caffeine 14.410.50.9 6.372.6 3.1 Carbaryl 56.652.2 2.9 5.192.39.8
o-Chlorophenyl thiourea32.615.3 2.2 6.847.07.4* 3,3'-Dichlorobenzidine24.821.70.7 2.989.6 2.4
3,3'-Dimethoxybenzidine31.629.2 2.37.392.37.7
3,3'-Dimethylbenzidine 31.731.8 1.0 3.1100.4 3.3 Diuron25.026.2 1.3 5.1104.8 4.4 Ethylene thiourea 32.00.00.00.00.0 * Linuron 95.089.5 3.9 4.194.213.1 Monuron31.231.8 1.2 3.8101.9 4.0 Rotenone 50.344.99.418.889.331.6 Siduron27.929.6 1.4 5.2106.3 4.7
* Not recovered
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ACCURACY AND PRECISION DATA FROM SEVEN DETERMINATIONS OF THE TARGET
COMPOUNDS IN ORGANIC-FREE REAGENT WATER USING SOLID-PHASE
EXTRACTION (C CARTRIDGE)18a
Mean Mean True Observed Std.Accuracy Conc.Conc.Dev.RSD (% of MDL Compound
(μg/L)(μg/L)(μg/L)(%)True)(μg/L)Benzidine
22.912.2 1.713.753.2 5.3Benzoylprop ethyl 32.529.3 2.0 6.990.2 6.3Caffeine 14.4 6.4 1.421.444.2 4.4Carbaryl
56.653.9 1.8 3.395.2 5.7o-Chlorophenyl thiourea 32.60.00.00.00.0*3,3'-Dichlorobenzidine 5.0 4.40.410.089.6 1.43,3'-Dimethoxybenzidine 31.625.5 1.87.180.8 5.73,3'-Dimethylbenzidine 31.731.4 1.0 3.199.0 3.0Diuron
25.024.4 1.4 5.697.6 4.4Ethylene thiourea 32.00.00.00.00.0*Linuron 95.088.9 4.8 5.493.615.1Monuron 31.230.5 2.99.697.89.1Rotenone 50.345.0 2.4 5.489.67.5Siduron
27.9
24.8
2.0
7.9
88.9
6.3
Reagent water contained 0.01 M ammonium acetate.
a
* Not recovered.
ACCURACY AND PRECISION DATA FROM SIX DETERMINATIONS OF THE TARGET COMPOUNDS IN ORGANIC-FREE REAGENT WATER USING SOLID-PHASE EXTRACTION (NEUTRAL POLYSTYRENE/DIVINYLBENZENE POLYMER DISK)
Mean Mean
True Observed Std.Accuracy
Conc.Conc.Dev.RSD(% of MDL Compound(μg/L)(μg/L)(μg/L)(%)True)(μg/L) Benzidine22.924.7 2.49.8108.08.1 Benzoylprop ethyl32.531.1 3.09.695.810.1 Caffeine 14.40.70.572.5 5.2 1.8 Carbaryl 56.659.5 4.77.9105.115.8
o-Chlorophenyl thiourea32.60.00.00.00.0*
3,3'-Dichlorobenzidine 5.0 5.00.59.4101.7 1.6
3,3'-Dimethoxybenzidine31.632.8 2.2 6.7103.87.4
3,3'-Dimethylbenzidine31.731.5 2.1 6.799.47.1 Diuron25.026.1 1.87.0104.5 6.1 Ethylene thiourea32.00.00.00.00.0* Linuron95.097.98.79.0103.029.3 Monuron31.234.4 2.57.3110.48.4 Rotenone50.340.5 6.014.880.520.2 Siduron27.926.8 1.0 3.696.1 3.4
* Not recovered.
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MEAN RECOVERIES, MULTI-LABORATORY PRECISION AND ESTIMATES OF SINGLE ANALYST PRECISION FOR THE MEASUREMENTS OF FOUR BENZIDINES BY LC/PB/MS
10 μg/L Test Conc.100 μg/L Test Conc.
RSD RSD RSD RSD
Recovery Multi-Single Recovery Multi-Single Compound(%)lab Analyst(%)lab Analyst Benzidine9610 5.697109.1
3,3'-Dimethoxybenzidine104201895107.0
3,3'-Dimethylbenzidine 981410978.6 4.9
3,3'-Dichlorobenzidine96189.4979.1 4.6
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AN UNACCEPTABLE CHROMATOGRAM WITH COLUMN BLEED
FIGURE 2
AN ACCEPTABLE CHROMATOGRAM FOLLOWING COLUMN FLUSHING
. 快适水水质卫生标准 1、快适水概念 水质指标达到美国、欧盟、日本和中国现行饮用水标准中最高要求，适合于婴幼儿等对水中污染物较为敏感的人群长期饮用的优质饮用水。 2、美国、日本、欧盟和中国四国或地区饮用水水质标准比较 2.1分类的区别 （1）美国水质标准分为国家一级饮用水水质标准和二级饮用水标准。国家一级饮用水水质标准中又有最大污染物浓度（MCL）和最大污染物浓度目标（MCLG）两个指标，MCL为强制性的标准，MCLG是非强制性的更高目标值。美国一级饮用水指标共有78个，分为：无机物、有机物、放射性物质、微生物学指标，其中无机物指标有15个，有机物指标54个，放射性物质指标有3个，微生物学指标有6个；二级饮用水污染物指标共有15个，没有细分。 （2）欧盟水质标准并没有特别分类，水质指标分为微生物学指标、化学物质指标和指示指标，其中微生物学指标2个（瓶桶装水是5个），化学物质指标26个，指示指标20个。 （3）日本水质标准分为水质基准项目和水质管理目标设定项目。水质指标项目分为病原微生物、重金属、无机物、金属类、有机物、消毒剂残留及消毒副生成物、基本特性、其他类。日本水质基准项目共50个，其中病原微生物指标有2个，重金属指标有10个，无机物指标有9个，有机物指标有11个，消毒剂和消毒副生成物10个，基本特性指标5个，其他类指标2个；水质管理目标设定项目共27个，其中重金属和金属指标有4个，无机物指标有2个，有机物指标有9个，消毒剂和消毒副生成物6个，其他类6个。 （4）中国生活饮用水卫生标准GB5749分为水质常规指标及限值、饮用水中消毒剂常规指标及要求、水质非常规指标及限值，共计106项。饮用水标准水质常规指标分为微生物指标、毒理指标、感官性状和一般化学指标、放射性指标四类共1 / 19 . 38个，其中微生物指标有4个，毒理指标有15个，感官性状和一般化学指标有17个，放射性指标2个；饮用水中消毒剂常规指标4个；水质非常规指标及限值分为微生物指标2个、毒理指标59个、感官性状和一般化学指标3个。 2.2水质指标对比 以中国生活饮用水卫生标准GB5749中水质常规指标及限值、水质非常规指标及限值为参照，中国、美国、日本和欧盟4个国家和地区的水质指标对比见表1和表2。 表1 水质常规指标及限值对比 限指中美日欧 GB5749-20MC6MCL标 、微生物指 总大肠菌51MPN/100m不得检CFU/100m 耐热大肠菌群MPN/100m不得检 CFU/100m
轻型汽车污染物排放限值及测量方法（中国Ⅲ、Ⅳ阶段）Limits and measurement methods for emissions from light-duty vehicles (Ⅲ, Ⅳ) (GB 18352.3—20052007-07-01实施) 为贯彻《中华人民共和国环境保护法》和《中华人民共和国大气污染防治法》，防治机动车污染物排放对环境的污染，改善环境空气质量，制订本标准。本标准规定了装用点燃式发动机的轻型汽车，在常温和低温下排气污染物、曲轴箱污染物、蒸发污染物的排放限值及测量方法，污染控制装置的耐久性要求，以及车载诊断（OBD）系统的技术要求及测量方法。本标准规定了装用压燃式发动机的轻型汽车，在常温下排气污染物的排放限值及测量方法，污染控制装置的耐久性要求，以及车载诊断（OBD）系统的技术要求及测量方法。本标准也规定了轻型汽车型式核准的要求，生产一致性和在用车符合性的检查与判定方法。本标准也规定了燃用LPG或NG轻型汽车的特殊要求。本标准也规定了作为独立技术总成、拟安装在轻型汽车上的替代用催化转化器，在污染物排放方面的型式核准规程。本标准适用于以点燃式发动机或压燃式发动机为动力、最大设计车速大于或等于50km/h的轻型汽车。本标准不适用于已根据GB 17691（第Ⅲ阶段或第Ⅳ阶段）规定得到型式核准的N1类汽车。 解读中国轻型汽车第Ⅲ、IV阶段排放标准GB18352.3-2005 https://www.doczj.com/doc/a76384212.html, [ 2005-8-30 11:28:29 ] 来源：中国汽车动态网? 李怀斌 [推荐] [大中小] [关闭窗口] 今年4月27日，国家环保总局公布了五项机动车污染物排放新标准。其 中与广大汽车生产企业最为密切的是GB18352.3-2005《轻型汽车污染物排放限 值及测量方法(中国Ⅲ、Ⅳ阶段)》(即中国轻型汽车第Ⅲ、Ⅳ号排放标准)，轻 型汽车第Ⅲ号排放标准自2007年7月1日起实施，第Ⅳ号排放标准自2010年
《美国饮用水水质标准》 国家一级饮用水规程（NPDWRs或一级标准），是法定强制性的标准，它适用于公用给水系统。一级标准限制了那些有害公众健康的及已知的或在公用给水系统中出现的有害污染物浓度，从而保护饮用水水质。 表1将污染物划分为：无机物，有机物，放射性核素及微生物。 表1
国家二级饮用水规程： 二级饮用水规程（NSDWRs或二级标准），为非强制性准则，用于控制水中对美容（皮肤，牙齿变色），或对感官（如嗅，味，色度，）有影响的污染物浓度。 美国环保局（EPA）为给水系统推荐二级标准但没有规定必须遵守，然而，各州可选择性采纳，作为强制性标准。 表2 注： ①、污染物最高浓度目标MCLG-对人体健康无影响或预期无不良影响的水中污染物浓度。它规定了确当的安全限量，MCLGs是非强制性公共健康目标。 ②、污染物最高浓度-它是供给用户的水中污染物最高允许浓度，MCLGs它是强制性标准，MCLG是安全限量，确保略微超过MCL限量时对公众健康不产生显著风险。 ③、TT处理技术-公共给水系统必须遵循的强制性步骤或技术水平以确保对污染物的控制。 ④、除非有特别注释，一般单位为mg/L。 ⑤、1986年安全饮水法修正案通过前，未建立MCLGs指标，所以，此污染物无MCLGs值。 ⑥、在水处理技术中规定，对用铅管或用铅焊的或由铅管送水的铜管现场取龙头水样，如果所取自来水样品中超过铜的作用浓度1.3mg/L，铅的作用浓度0.015mg/L的10%，则需进行处理。 ⑦、如给水系统采用丙烯酰胺及熏杀环（1-氯-2，3环氧丙烷），它们必须向州政府提出书面形式证明（采用第三方或制造厂的证书），它们的使用剂量及单体浓度不超过下列规定；丙烯酰胺=0.05%，剂量为1mg/L（或相当量） 熏杀环=0.01%，剂量为20mg/L（或相当量） ⑧、地表水处理规则要求采用地表水或受地面水直接影响的地下水的给水系统，（1）进行水的消毒，并（2）为满足无须过滤的准则，要求进行水的过滤，以满足污染物能控制到下列浓度： 贾第氏虫，99.9%杀死或灭活 病毒99.99%杀死或灭活
美国汽车排放标准 美国有加州及联邦两个标准。美国加州最早控制汽车排放，而且标准也最严。1963年制订了“大气清洁法”；1966年加州制订“7工况法”，颁布汽车排放控制标准；1968年联邦采用“7工况法”开始控制汽车排放；1972年联邦采用LA-4C(FTP-72)试验规范，并增加对NO X的控制；1975年改用LA-4H(FTP-75)，并一直延续使用至今。1975年起到80年代，美国排放标准大幅度加严，特别强化对NO X的限值，同时再提高对HC和CO的控制，1983年排放标准一直维持到1993年。1990年美国国会修订了“清洁空气法”，对汽车排放提出更加严格的要求。表11-1是联邦轿车排放标准。联邦分两阶段加严排放标准，对HC的排放限制不仅指总碳氢(THC)，而要限制非甲烷碳氢化物(NMHC)，另外新标准增加对排放稳定性(使用寿命)的考核，提出8万英里和16万英里两个排放限值(见表11-2)。 美国联邦轻型车排放控制标准(g/mile) 表11-1 美国轻型汽车排放限值(FTP-75测试循环) (g／km) 表11-2 （1）微粒排放只用于柴油车 1994年加州颁布了清洁燃料和低排放汽车计划CF/LEV，规定从1995年起实施严格的低污染汽车标准（LEV），分四阶段进行：即过渡低排放车(TLEV)、低排放车(LEV)、超低排放车(ULEV)和零污染车和（ZEV）。表11-3是加州轿车排放限值。 美国加州轻型汽车排放限值(g/km) 保证里程80000km 表11-3
美国联邦49个州和加利福尼亚州的重型车用柴油机的排放限值见表11-4。 美国重型车用柴油机的排放
美国EPA通用土壤筛选值
美国EPA通用土壤筛选值
CAS 号污染 物 土壤（mg/kg） 地下 （μg/L 居 住 备 注 工 业 备 注 基于 地下 水保 护 饮用 水 1 +04 E+0 5 +00 +04 75-86- 5 丙酮氰 醇 2.0E +02 n 2.1 E+0 3 n 1.2E -02 5.8E +01 75-05- 8 乙腈 8.7E +02 n 3.7 E+0 3 n 2.6E -02 1.3E +02 98-86- 2 乙酰苯 7.8E +03 ns 1.0 E+0nms 1.1E +00 3.7E +03
CAS 号污染 物 土壤（mg/kg） 地下 （μg/L 居 住 备 注 工 业 备 注 基于 地下 水保 护 饮用 水 -8 -01 E-0 1 -06 -02 79-06- 1 丙烯酰 胺 2.3E -01 c 3.4 E+0 c 9.1E -06 4.3E -02 79-10- 7 丙烯酸 3.0E +04 n 2.9 E+0 5 nm 3.7E +00 1.8E +04 107-13 -1 丙烯腈 2.4E -01 c* 1.2 E+0c* 9.9E -06 4.5E -02
CAS 号污染 物 土壤（mg/kg） 地下 （μg/L 居 住 备 注 工 业 备 注 基于 地下 水保 护 饮用 水 60-8 +00 E+0 1 -04 +00 116-06 -3 涕灭威 6.1E +01 n 6.2 E+0 2 n 9.1E -03 3.7E +01 1646-8 8-4 涕灭威 砜 6.1E +01 n 6.2 E+0 2 n 8.0E -03 3.7E +01 309-00 -2 艾氏剂 2.9E -02 c* 1.0 E-0 c 6.5E -04 4.0E -03
美国饮用水水质标准 1996年10月版 —————————————————————————————————— ————— 美国国家一级饮用水水质标准是应用于公众给水系统的强制性法律标准。一级饮用水水质标准通过限制对损害公众健康的污染物的浓度水平以到达保护饮用水水质的目的。二级饮用水标准为非强制性标准。 国家一级饮用水法规
国家二级饮用水法规
注：1．最大污染物浓度指标值（MCLG）--饮用水中的污染物不会对人体健康产生未知或不利影响的最大浓度。MCLG是非强制性健康指标。 2．最大污染物浓度（MCL）--公共供水系统的用户水中污染物的最大允许浓度。MCL是强制性标准。MCLG中的安全极限要确保检测值略微超过MCL不会对公共健康产生重大危害。 3．处理技术--公共供水系统必须遵循的强制性处理方法，以保证污染物的控制。 4．除特别指明外，单位微mg/L。 5．1986年安全饮用水法案修正案颁布前没有建立MCLG，因此该污染物没有MCLG。 6．当采用含铅管道和铜管时，需要在用户水龙头处取样。当10%自来水水样中铅和铜超标时，需要考虑采用技术处理的活性浓度分别为：铅0.015mg/L和铜0.3mg/L。 7．每个供水系统必须书面向政府保证，在饮用水系统中使用丙烯酰胺和3-氯-1，2-环氧丙烷时，聚合体投加量和单体浓度不应超过以下规定： 丙烯酰胺=0.05%（投加量为1 mg/L时） 环氧氯丙烷=0.01%（投加量为20 mg/L时） 8．地表水处理法规（SWTR）规定，采用地表水的处理系统必须做到消毒和过滤工艺，确保以下污染物得到控制： 兰伯氏贾第虫：99.9％失活 病毒：99.9％失活 军团菌：没有限值。EPA认为如果贾第氏虫和病毒失活，军团菌也能得到控制 浊度：任何时候浊度不准许大于5NTU；对有滤池的系统，任何连续2个月中，95%的每日所取水样浊度不能大于1NTU（直接过滤不能大于0.5NTU） HPC：每毫升不大于500个细菌群 9．每月总大肠菌超标水样不大于5.0%（对每月采集不足40个水样的供水系统，总大肠菌超标数不大于1个）。含有大肠菌的水样必须进一步分析粪型大肠菌。水样中不应含有大肠菌。
美国饮用水水质标准 美国国家一级饮用水水质标准是应用于公众给水系统的强制性法律标准。一级饮用水水质标准通过限制对损害公众健康的污染物的浓度水平以到达保护饮用水水质的目的。二级饮用水标准为非强制性标准。 国家一级饮用水法规 本标准规定了生活饮用水水源的水质指标、水质分级、标准限值、水质检验以及标准的监督执行。 本标准适用于城乡集中式生活饮用水的水源水质（包括各单位自备生活饮用水的水源）。分散式生活饮用水水源的水质，亦应参照使用。 序号污染物MCLG1（MG/L） 4 MCL2或TT3（MG/L） 无机物 1 锑0.006 0.006 2 砷无5 0.05 3 石棉（纤维＞10微米）7×106纤维/L 7×106纤维/L 4 钡 2 2 5 铍0.004 0.004 6 镉0.005 0.005 7 铬（总）0.1 0.1 8 铜 1.3 参考指标=1.3 TT6 9 氟化物 4.0 4.0 10 铅0 参考指标=0.015 TT6 11 无机汞0.002 0.002 12 硝酸盐（以氮计）10 10 13 亚硝酸盐（以氮计） 1 1 14 硒0.05 0.05 15 铊0.0005 0.002 有机物 16 丙烯酰胺0 TT 17 草不绿0 0.002 18 莠去津0.003 0.003 19 苯0 0.005 20 苯并[a]芘0 0.0002 21 呋喃丹0.04 0.04 22 四氯化碳0 0.005 23 氯丹0 0.002 24 氯苯0.1 0.1 25 2，4-D 0.07 0.07 26 茅草枯0.2 0.2 27 1，2-二溴-3-氯丙烷（DBCP）0 0.0002 28 对二氯苯0.6 0.6 29 邻二氯苯0.075 0.075 30 1，2-二氯乙烷0 0.005
METHOD 3520C CONTINUOUS LIQUID-LIQUID EXTRACTION 1.0SCOPE AND APPLICATION 1.1This method describes a procedure for isolating organic compounds from aqueous samples. The method also describes concentration techniques suitable for preparing the extract for the appropriate determinative steps described in Sec. 4.3 of Chapter Four. 1.2This method is applicable to the isolation and concentration of water-insoluble and slightly soluble organics in preparation for a variety of chromatographic procedures. 1.3Method 3520 is designed for extraction solvents with greater density than the sample. Continuous extraction devices are available for extraction solvents that are less dense than the sample. The analyst must demonstrate the effectiveness of any such automatic extraction device before employing it in sample extraction. 1.4This method is restricted to use by or under the supervision of trained analysts. Each analyst must demonstrate the ability to generate acceptable results with this method. 2.0SUMMARY OF METHOD 2.1 A measured volume of sample, usually 1 liter, is placed into a continuous liquid-liquid extractor, adjusted, if necessary, to a specific pH (see Table 1), and extracted with organic solvent for 18 - 24 hours. 2.2The extract is dried, concentrated (if necessary), and, as necessary, exchanged into a solvent compatible with the cleanup or determinative method being employed (see Table 1 for appropriate exchange solvents). 3.0INTERFERENCES 3.1Refer to Method 3500. 3.2The decomposition of some analytes has been demonstrated under basic extraction conditions required to separate analytes. Organochlorine pesticides may dechlorinate, phthalate esters may exchange, and phenols may react to form tannates. These reactions increase with increasing pH, and are decreased by the shorter reaction times available in Method 3510. Method 3510 is preferred over Method 3520 for the analysis of these classes of compounds. However, the recovery of phenols may be optimized by using Method 3520 and performing the initial extraction at the acid pH. 4.0APPARATUS AND MATERIALS 4.1Continuous liquid-liquid extractor - Equipped with polytetrafluoroethylene (PTFE) or glass connecting joints and stopcocks requiring no lubrication (Kontes 584200-0000, 584500-0000, 583250-0000, or equivalent). CD-ROM3520C - 1Revision 3 December 1996
《美国饮用水水质标准》（EPA） [标题]：《美国饮用水水质标准》 [颁布者]：美国 [编号]： [颁布日期]： [实施日期]： [有效性]：有效 国家一级饮用水规程（NPDWRs或一级标准），是法定强制性的标准，它适用于公用给水系统。一级标准限制了那些有害公众健康的及已知的或在公用给水系统中出现的有害污染物浓度，从而保护饮用水水质。 表1将污染物划分为：无机物，有机物，放射性核素及微生物。 表1
国家二级饮用水规程：
二级饮用水规程（NSDWRs或二级标准），为非强制性准则，用于控制水中对美容（皮肤，牙齿变色），或对感官（如嗅，味，色度，）有影响的污染物浓度。 美国环保局（EPA）为给水系统推荐二级标准但没有规定必须遵守，然而，各州可选择性采纳，作为强制性标准。 表2 注： ①、污染物最高浓度目标MCLG-对人体健康无影响或预期无不良影响的水中污染物浓度。它规定了确当的安全限量，MCLGs是非强制性公共健康目标。 ②、污染物最高浓度-它是供给用户的水中污染物最高允许浓度，MCLGs它是强制性标准，MCLG是安全限量，确保略微超过MCL限量时对公众健康不产生显著风险。 ③、TT处理技术-公共给水系统必须遵循的强制性步骤或技术水平以确保对污染物的控制。 ④、除非有特别注释，一般单位为mg/L。 ⑤、1986年安全饮水法修正案通过前，未建立MCLGs指标，所以，此污染物无MCLGs值。 ⑥、在水处理技术中规定，对用铅管或用铅焊的或由铅管送水的铜管现场取龙头水样，如果所取自来水样品中超过铜的作用浓度1.3mg/L，铅的作用浓度
0.015mg/L的10%，则需进行处理。 ⑦、如给水系统采用丙烯酰胺及熏杀环（1-氯-2，3环氧丙烷），它们必须向州政府提出书面形式证明（采用第三方或制造厂的证书），它们的使用剂量及单体浓度不超过下列规定； 丙烯酰胺=0.05%，剂量为1mg/L（或相当量） 熏杀环=0.01%，剂量为20mg/L（或相当量） ⑧、地表水处理规则要求采用地表水或受地面水直接影响的地下水的给水系统，（1）进行水的消毒，并（2）为满足无须过滤的准则，要求进行水的过滤，以满足污染物能控制到下列浓度： 贾第氏虫，99.9%杀死或灭活 病毒99.99%杀死或灭活 军团菌未列限值，EPA认为，如果一旦贾第氏虫和病毒被灭活，则它就已得到控制。 浊度，任何时候浊度不超过5NTU，采用过滤的供水系统确保浊度不大于是NTU，（采用常规过滤或直接过滤则不大于0.5NTU），连续两个月内，每天的水样品中合格率至少大于95%。 HPC每毫升不超过500细菌数。 ⑨、每月总大肠杆菌阳性水样不超过5%，于每月例行检测总大肠杆菌的样品少于40只的给水系统，总大肠菌阳性水样不得超过1个。含有总大肠菌水样，要分析粪型大肠杆菌，粪型大肠杆菌不容许存在。 ⑩、粪型及艾氏大肠杆菌的存在表明水体受到人类和动物排泄物的污染，这些排泄物中的微生物可引起腹泻，痉挛，恶心，头痛或其它症状。 岳宇明译 岳舜琳校
潜在致癌剂的危害等 级 致癌性是筛选优先污染物的重要依据之一，下表列出了美国EPA公布的200种致癌剂的危害等级。其中的参数含义为： 1、证据的充分程度（Degree of Evidence） 化学品对人体的致癌性证据之充分程度可以分为下列几类。 （1）证据充分，指致癌剂和人体癌症之间有因果关系。 （2）证据有限，指能提供一些可信的致癌性证据，但证据尚有限，还需作进一步补充。 （3）证据不充分，可能有3种情况，①能获取的致癌性数据很少；②与证据有关的研究尚不能排除偶然性、误差及混淆等情况；③研究结果无致癌性证据。 根据动物实验取得的致癌性证据的充分程度可分4级。 1级，致癌性证据充分。 2级，致癌性证据有限。 3级，致癌性证据不充分。 4级，无致癌性证据。 2、IARC标准分组 国际癌症研究所 （International Agency for research on cancer，简称IARC）将人类的肿瘤风险分为3组。 1组：列在此组内的化学品属致癌物，流行病学和暴露实验均已肯定，基致癌证据是充分的。 2组：化学品可能对人体有致癌性。其中有的对人体的致癌性证据几乎是“充分的”，另一类的证据不够充分。证据程度较高的为A组，较低的为B 组。例如，2A指对人体的致癌性至少存在着有限证据。当动物证据充分而人体数据不充分时，归入2B。 3组：列在本组中的化学品对人类没有致癌性。
3、潜力因素值F（Potency Factor Estimate） 潜力因素值F定义为1/ED 10。ED 10 等于10%终身致癌风险的致癌剂剂量。 F可以和致癌性的确认证据一起，用来划分化学品潜在致癌性的危险等级。 4、潜力因素分组（Potency factor Grouping） 由于潜力因素值F可表示致癌危险性的相对大小，因而，可将潜在致癌剂的相对潜力因素分为4组。潜力因素最高的化学品分在1组，中等潜力因素的为2组，低潜力因素的为3组，最低潜力因素的为4组。 5、致癌危害等级（Cancer Hazard Ranking） 根据人和动物试验所取得的致癌性证据，结合潜力因素分组数据，可将化学品致癌危害等级分为高、中、低3级。
全球饮用水水质标准 人类对饮用水安全的关注 饮用水的安全性对人体健康至关重要。进入二十世纪九十年代以来,随着微量分析和生物检测技术的进步,以及流行病学数据的统计积累,人们对水中微生物的致病风险和致癌有机物、无机物对健康的危害,认识不断深化,世界卫生组织和世界各国相关机构纷纷修改原有的或制订新的水质标准。了解和把握国际水质的现状与趋势,对于我们重新审视和修订已沿用多年的现行国家饮用水水质标准,满足新形势下我国城乡居民对饮水水质新的需求,加强对人体健康的保护,具有十分重要的意义。 １.饮用水水质标准的现状 目前，全世界具有国际权威性、代表性的饮用水水质标准有三部：世界卫生组织（WHO）的《饮用水水质准则》、欧盟（EC）的《饮用水水质指令》以及美国环保局（USEPA）的《国家饮用水水质标准》，其它国家或地区的饮用水标准大都以这三种标准为基础或重要参考，来制订本国国家标准。如东南亚的越南、泰国、马来西亚、印度尼西亚、菲律宾、香港，以及南美的巴西、阿根廷，还有南非、匈牙利和捷克等国家都是采用WHO的饮用水标准；欧洲的法国、德国、英国（英格兰和威尔士、苏格兰）等欧盟成员国和澳门则均以EC指令为指导；而其它一些国家如澳大利亚、加拿大、俄罗斯、日本同时参考WHO、EC、USEPA标准；我国和我国的台湾省则有自行的饮用水标准。 三部重要的水质标准 世界卫生组织制订的《饮用水水质准则》作为世界性的权威水质标准，是各国制订水质标准的重要参考，并随着全球经济的迅猛增长和人类对健康的日益重视而不断发展。考虑到全球多个国家地方社会习俗、经济、文化、环境的差异，因而水质指标较完整,但指标值并非是严格的限定标准,各国可根据本国实际情况进行适当调整。在1993年到1997年期间，WHO分三卷出版了《饮用水水质准则》第二版，其中包括：第一卷，建议书（1993）；第二卷，健康标准及其它相关信息（1996）；第三卷，公共供水的监控（1997）。最近WHO在《准则》中增加了"微囊藻毒素"指标，表明对蓝藻产生的藻毒素的健康影响给予高度重视。 欧共体（欧盟前身）理事会在1980年对各成员国提出《饮用水水质指令》(80/778/EC),指标比较完整,要求也比较高。该指令成为欧洲各国制订本国水质标准的主要框架。1991年底,欧盟成员国供水协会对《饮用水水质指令》80/778/EC实施以来的情况作了总结,认为尽管该指令对10年来欧洲饮用水水质的改善起到重要的推动作用,但在执行过程中也暴露出一些缺点：未能提供合适的法律架构以应对原水水质的变化,以及生产、输送饮用水所遇到技术困难；此外,该指令在1975年开始起草,其中的指导思想和水质参数在当时的情况下是适宜的,但没有将近年来水行业的科技进步纳入其中。由此,1995年,欧盟对80/778/EEC进行了修正,1998年11月通过了新指令98/83/EC。指标参数由66项减少至48项（瓶装水为50项）。新指令更加强调指标值的科学性,与WHO指导标准的一致性。 美国国家饮用水水质标准分一级规则和二级规则两部分。一级规则是强制性标准,通过规定最大污染物浓度或处理技术来执行。美国最新国家饮用水水质标准（2001年3月颁布）,共列了101项（包括计划实施的），分为两部分,一级法规（强制性标准），共86项指标,其中无机物16项,有机物35项,农药19项,消毒剂及消毒副产物7项,微生物学指标7项,放射性指标4项；二级法规（非强制性标准），
各个国家有各个国家的不同啊 不能一概而论 汽车排放与欧洲标准 汽车排放是指从废气中排出的CO（一氧化碳）、HC＋NOx（碳氢化合物和氮氧化物）、PM（微粒，碳烟）等有害气体。它们都是发动机在燃烧作功过程中产生的有害气体。这些有害气体产生的原因各异，CO是燃油氧化不完全的中间产物，当氧气不充足时会产生CO，混合气浓度大及混合气不均匀都会使排气中的CO增加。HC是燃料中未燃烧的物质，由于混合气不均匀、燃烧室壁冷等原因造成部分燃油未来得及燃烧就被排放出去。NOx是燃料（汽油）在燃烧过程中产生的一种物质。PM也是燃油燃烧时缺氧产生的一种物质，其中以柴油机最明显。因为柴油机采用压燃方式，柴油在高温高压下裂解更容易产生大量肉眼看得见的碳烟。为了抑制这些有害气体的产生，促使汽车生产厂家改进产品以降低这些有害气体的产生源头，欧洲和美国都制定了相关的汽车排放标准。其中欧洲标准是我国借鉴的汽车排放标准，目前国产新车都会标明发动机废气排放达到的欧洲标准。 欧洲标准是由欧洲经济委员会（ECE）的排放法规和欧共体（EEC）的排放指令共同加以实现的，欧共体（EEC）即是现在的欧盟（EU）。排放法规由ECE参与国自愿认可，排放指令是EEC 或EU参与国强制实施的。汽车排放的欧洲法规（指令）标准1992年前巳实施若干阶段，欧洲从1992年起开始实施欧Ⅰ（欧Ⅰ型式认证排放限值）、1996年起开始实施欧Ⅱ（欧Ⅱ型式认证和生产一致性排放限值）、2000年起开始实施欧Ⅲ（欧Ⅲ型式认证和生产一致性排放限值）、2005年起开始实施欧Ⅳ（欧Ⅳ型式认证和生产一致性排放限值）。 目前在我国新车常用的欧Ⅰ和欧Ⅱ标准等术语，是指当年EEC颁发的排放指令。例如适用于重型柴油车（质量大于3.5吨）的指令“EEC88/77”分为两个阶段实施，阶段A（即欧Ⅰ）适用于1993年10月以后注册的车辆；阶段B（即欧Ⅱ）适用于1995年10月以后注册的车辆。 汽车排放的欧洲法规（指令）标准的内容包括新开发车的型式认证试验和现生产车的生产一致性检查试验，从欧Ⅲ开始又增加了在用车的生产一致性检查。 汽车排放的欧洲法规（指令）标准的计量是以汽车发动机单位行驶距离的排污量（g/km）计算，因为这对研究汽车对环境的污染程度比较合理。同时，欧洲排放标准将汽车分为总质量不超过3500公斤（轻型车）和总质量超过3500公斤（重型车）两类。轻型车不管是汽油机或柴油机车，整车均在底盘测功机上进行试验。重型机由于车重，则用所装发动机在发动机台架上进行试验。 欧盟国家努力实现对“京都议定书”的承诺，为减少汽车尾气排放污染，保护大气环境而采取的各项措施。 推广高效、低耗和低污染的“清洁汽车”，成为今年活动的焦点。欧洲各国一面不断升级汽车尾气排放标准，一面大力宣扬新的城市交通观念。但是，绝对“清洁”的汽车目前尚不存在，
DETERMINATION OF ETHYLENE THIOUREA (ETU) IN WATER USING GAS CHROMATOGRAPHY WITH A NITROGEN-PHOSPHORUS DETECTOR Revision 1.0 December 1992 D.J. Munch and R.L. Graves T.M. Engel and S.T. Champagne Battelle, Columbus Division ENVIRONMENTAL MONITORING SYSTEMS LABORATORY OFFICE OF RESEARCH AND DEVELOPMENT U.S. ENVIRONMENTAL PROTECTION AGENCY CINCINNATI, OHIO 45268 509-1
DETERMINATION OF ETHYLENE THIOUREA (ETU) IN WATER USING GAS CHROMATOGRAPHY WITH A NITROGEN-PHOSPHORUS DETECTOR 1.0SCOPE AND APPLICATION 1.1This method utilizes gas chromatography (GC) to determine ethylene thiourea (ETU, Chemical Abstracts Registry No. 96-45-7) in water. 1.2This method has been validated in a single laboratory during development. 1 The method detection limit (MDL) has been determined in reagent water and is listed in Table 2. Method detection limits may vary among laboratories, depending upon the analytical instrumentation used and the experience of the analyst. In addition to the work done during the development of this method and its use in the National Pesticide Survey, an interlaboratory method validation study of this method has been conducted. 1.3This method is restricted to use by or under the supervision of analysts experienced in the use of GC and in the interpretation of gas chromatograms. Each analyst must demonstrate the ability to generate acceptable results with this method using the procedure described in Section 9.3. 1.4When a tentative identification of ETU is made using the recommended primary GC column (Section 6.7.1), it must be confirmed by at least one additional qualitative technique. This technique may be the use of the confirmation GC column (Section 6.7.2) with the nitrogen-phosphorus detector or analysis using a gas chromatograph/mass spectrometer (GC/MS). 2.0SUMMARY OF METHOD 2.1The ionic strength and pH of a measured 50 mL aliquot of sample are adjusted by addition of ammonium chloride and potassium fluoride. The sample is poured onto an Extrelut column. ETU is eluted from the column in 400 mL of methylene chloride. A free radical scavenger is then added in excess to the eluate. The methylene chloride eluant is concentrated to a volume of 5 mL after solvent substitution with ethyl acetate. Gas chromatographic conditions are described which permit the separation and measurement of ETU with a nitrogen-phosphorus detector (NPD). 3.0DEFINITIONS 3.1Artificial Ground Water -- An aqueous matrix designed to mimic a real ground water sample. The artificial ground water should be reproducible for use by others. 509-2
重庆润通2008-12-18 1 美国通机EPA 第三阶段法规新 要求介绍 天津内燃机研究所第一研究室 贾滨
重庆润通 2008-12-18 2 III, IV, V 类发动机 string trimmer chainsaw edger leaf blower Sales: 12 million/year+
重庆润通2008-12-18 3 generator walk-behind mower zero-turn mower riding mower pressure washer generator Sales: 10 million/year+ Sales: 4 million/year+ ? I 类发动机 II 类发动机
重庆润通2008-12-184 美国EPA 检查出的不符合满足法规要求 的主要方面 –标签上没有写明EPA 发动机系族名称和发动机制造商的名称; –发动机的型号没有包括在认证申报文件中; –催化器的问题:缺失或者性能达不到要求; –标签可以被完整的撕下来;– 排放标签内容有问题
重庆润通2008-12-18 5 美国EPA 对于不符合要求进口产品的策略 ?Outreach 联手 ?Target most significant violators 将目标锁定在显著违反法规的情况?Inspect and test representative samples of engines and catalysts 检查和测试有代表性的发动机和催化器样品 ?Leverage resources with Customs, Regions, States, Manufacturers, and Retailers 使用海关,地区,州,生产商和零售商的资源 ?Address the Flow of noncompliant Products 搞清楚不符合要求产品的流向 ?Upcoming North American auditing program 即将到来的北美稽查计划 ? 美国EPA 于2007年12月已经与国家质量监督检验总局签署合作备忘录, 将加强进出口产品的检验
METHOD TO-1 Revision 1.0 April, 1984 METHOD FOR THE DETERMINATION OF VOLATILE ORGANIC COMPOUNDS IN AMBIENT AIR USING TENAX? ADSORPTION AND GAS CHROMATOGRAPHY/MASS SPECTROMETRY (GC/MS) 1.Scope 1.1The document describes a generalized protocol for collection and determination of certain volatile organic compounds which can be captured on Tenax? GC (poly(2,6- Diphenyl phenylene oxide)) and determined by thermal desorption GC/MS techniques. Specific approaches using these techniques are described in the literature (1-3). 1.2This protocol is designed to allow some flexibility in order to accommodate procedures currently in use. However, such flexibility also results in placement of considerable responsibility with the user to document that such procedures give acceptable results (i.e., documentation of method performance within each laboratory situation is required). Types of documentation required are described elsewhere in this method. 1.3Compounds which can be determined by this method are nonpolar organics having boiling points in the range of approximately 80E - 200E C. However, not all compounds falling into this category can be determined. Table 1 gives a listing of compounds for which the method has been used. Other compounds may yield satisfactory results but validation by the individual user is required. 2.Applicable Documents 2.1ASTM Standards: D1356Definitions of Terms Related to Atmospheric Sampling and Analysis. E355Recommended Practice for Gas Chromatography Terms and Relationships. 2.2Other documents: Existing procedures (1-3).