Concentrations and compositions of organochlorine contaminants in sediments,soils,crustaceans,?shes and birds collected from Lake Tai,Hangzhou Bay and Shanghai city region,China
Haruhiko Nakata a ,*,Yuko Hirakawa a ,Masahiro Kawazoe a ,Tetsuji Nakabo b ,
Koji Arizono c ,Shin-Ichi Abe a ,Takeshi Kitano a ,Hideaki Shimada d ,
Izumi Watanabe e ,Weihua Li f ,Xucheng Ding f
a
Graduate School of Science and Technology,Kumamoto University,2-39-1Kurokami,Kumamoto 860-8555,Japan
b
The Kyoto University Museum,Kyoto University,Sakyo-ku,Kyoto 606-8501,Japan
c
Faculty of Environmental and Symbiotic Sciences,Kumamoto Prefectural University,3-1-100Tsukide,Kumamoto 862-8502,Japan
d
Faculty of Education,Kumamoto University,2-39-1Kurokami,Kumamoto 860-8555,Japan
e
Faculty of Agriculture,Tokyo University of Agriculture and Technology,3-5-8Saiwai-cho,Fuchuu-city,Tokyo 183-8509,Japan
f
Shanghai Institute of Planned Parenthood Research,2140Xie Tu road,Shanghai 200032,P.R.China
Received 28February 2004;accepted 2July 2004
Elevated concentrations of DDTs were detected in sediments,soils,and wildlife collected from China.
Abstract
Contamination by persistent organochlorines (OCs),such as DDTs,hexachlorocyclohexane isomers (HCHs),chlordane compounds (CHLs),hexachlorobenzene (HCB)and polychlorinated biphenyls (PCBs)were examined in sediments,soils,?shes,crustaceans,birds,and aquaculture feed from Lake Tai,Hangzhou Bay,and in the vicinity of Shanghai city in China during 2000and 2001.OCs were detected in all samples analyzed,and DDT and its metabolites were the predominant contaminants in most sediments,soils and biota.Concentrations of p,p #-DDT and ratio of p,p #-DDT to P DDTs were signi?cantly higher in marine ?shes than those in freshwater ?shes.While the use of DDTs has been o?cially banned in China since 1983,these results indicate a recent input of technical DDTs into the marine environment around Hangzhou https://www.doczj.com/doc/b415376857.html,parison of organochlorine concentrations in ?shes collected from Lake Tai and Hangzhou Bay suggests the presence of local sources of HCHs,chlordanes and PCBs at Lake Tai.Higher proportions of penta-and hexa-PCB congeners in ?shes at Lake Tai may suggest the use of highly chlorinated PCB product,such as PCB 5,around this lake.To our knowledge,this is a ?rst comprehensive study to examine the present status of organochlorine contamination in various environmental media,such as sediments,soils and wildlife,in China.ó2004Elsevier Ltd.All rights reserved.
Keywords:Organochlorines;Sediment;Soil;Fish;Bird;China
1.Introduction
Over the past few decades,the occurrence of organochlorines (OCs)in the environment is of great concern due to their persistent and long-range trans-portable nature as well as toxic biological e?ects (Tanabe et al.,1994;Wania and Mackay,1996).In May 2001,the ‘Stockholm Convention on Persistent Organic Pollutants’(POPs Treaty)adopted by the United Nations of Environmental Programme (UNEP)highlighted the need to control the global contamination by toxic environmental chemicals.The treaty promotes the global regulations on the production and usage of
*Corresponding author.Tel./fax:C 81963423380.
E-mail address:nakata@sci.kumamoto-u.ac.jp (H.Nakata).0269-7491/$-see front matter ó2004Elsevier Ltd.All rights reserved.doi:10.1016/j.envpol.2004.07.003
Environmental Pollution 133(2005)
415–429
https://www.doczj.com/doc/b415376857.html,/locate/envpol
persistent OCs,such as aldrin,dieldrin,endrin,hepta-chlor,chlordanes,hexachlorobenzene,mirex,toxa-phene,PCBs and DDTs.While most of developed countries have already banned or restricted the pro-duction and usage of these compounds,some developing countries still use OCs for agricultural and the public health purposes(Tanabe et al.,1994;Monirith et al., 2003).Several studies have reported the elevated concentrations of OCs in?shes,mussels and birds collected from Asian countries,such as India,Vietnam and China(Kannan et al.,1995;Kunisue et al.,2003; Monirith et al.,2003),indicating the presence of signi?cant source of OCs in this region.
It is well known that organochlorine pesticides were widely used in China between the1950s and the1980s (Li et al.,1998).The amount of HCHs and DDTs production in China is 4.9and0.4million tones, respectively,accounting for33and20%of the total world production(Zhang et al.,2002).After the ban on their usage in1983,the concentrations of organochlo-rine pesticides have decreased signi?cantly in foodstu?s (Nakata et al.,2002)and human breast milk(Wong et al.,2002)during the past10–20years in China.In contrast,some studies have reported the presence of elevated levels of organochlorine pesticides,such as DDTs and HCHs,in seawater and sediments in China (Zhou et al.,2001).Furthermore,DDT concentrations in marine mussels collected from China were still high, one to two orders of greater than those of other Asian countries(Nakata et al.,2002;Monirith et al.,2003). These results suggest signi?cant pollution sources of organochlorine pesticides are present in China,although the use of DDTs has been o?cially banned in1983.
In recent years,several studies have reported OCs contamination in China.However,most studies exam-ined OC levels in waters,sediments and mussels from the marine environment,and little information is available on OC contamination in freshwater samples as well as the higher trophic wildlife.In this study,we analyzed persistent organochlorines,such as DDTs, HCHs,PCBs,chlordanes and hexachlorobenzene (HCB)in sediments,soils,?shes,crustaceans and birds from freshwater and marine ecosystems in middle eastern China collected during2000and2001.
2.Materials and methods
2.1.Samples
Seventy-three samples were analyzed for OCs in this study.Details of the samples analyzed are shown in Table1.In Lake Tai and its vicinity(Fig.1,St.1), sediments,soils,?shes including four species(carp [Cyprinus carpio],topmouth culter[Erythroculter ilishaeformis],spotted steed[Hemibarbus maculatus] and cat?sh[scienti?c name unknown]),crustaceans (shrimps)and birds(thick-billed reed warbler [Acrocephalus aedon])were collected in August2000. Carp were also obtained from a?shpond near Lake Tai, and aquaculture feeds were also https://www.doczj.com/doc/b415376857.html,ke Tai, located at approximately90km west of Shanghai city,is known as the third largest freshwater lake in China.It has a surface area of2440km2(average water depth of less than2m),and supports more than60million people in its watershed(Wang et al.,2001).
Sediments and soils were collected downstream of the Huangpu River(a tributary of the Chang Jiang River),?shpond and creek around Shanghai city in April2001 (Fig.1,St.2).Shanghai is one of the biggest commercial and industrial cities known to have developed rapidly in China.Marine sediments,crustaceans(shrimps)and ?shes including11species(bluespotted mudskipper [Boleophthalmus pectinirostris],silver pomfret[Pampus echinogaster],spiny-head croaker[Collichthys lucidus], halfsmooth tongue?sh[Cynoglossus semilaevis],Bombay duck[Harpadon nehereus],trident goby[Tridentiger barbatus],redeye mullet[Chelon haematocheilus],pike eel[Muraenesox cinereus],needle?sh[Strongylura anas-tomella],cutlass?sh[Trichiurus japonicus],and?le?sh [Stephanolepis cirrhifer])were collected from Jingshan, north eastern Hangzhou Bay in September2001(Fig.1, St.3).Hangzhou Bay is located on the middle eastern coast of China.It has been in?uenced by hydrography and the sedimentation by the Chang Jiang River,which is one of the largest rivers in the world.Marine and freshwater sediments,soils and crustaceans(crabs)were collected from Haining in September2001(Fig.1,St.4). Haining is a rural area with large agricultural?elds towards west of Hangzhou Bay.We also collected marine sediments and soils from Shaoxing city in September2001(Fig.1,St.5).Shaoxing city is located south of Hangzhou Bay(approximately230km from Shanghai)and its population is4.29million.
All biological samples were obtained by netting or purchased in?sh markets of each sampling stations.All the samples were sealed in plastic bags and stored at ?20 C until chemical analysis.
2.2.Chemical analysis
Organochlorine compounds were analyzed according to the methods described previously(Nakata et al., 2002).The whole bodies of?shes,crustaceans and birds (except feather)were homogenized by using a manual homogenizer.Approximately10–25g of homogenized tissues were ground with sodium sulfate and extracted with mixed solvents of dichloromethane and hexane (8:1)for7h using a Soxhlet apparatus.A portion of the extract was used for lipid content measurement by evaporating the solvent until a constant weight was
416H.Nakata et al./Environmental Pollution133(2005)415–429
obtained.Sediment and soil samples were freeze-dried and passed through a 200-m m mesh sieve.An aliquot of the samples (20–25g)was Soxhlet-extracted as described above for 10h.
Seven 13C labeled tri-through deca-CB congeners (CB-28,-52,-101,-153,-138,-180and -209)were spiked into the extracts as the surrogates,and transferred to a glass column packed with Florisil,followed by elution with acetonitrile containing 20%hexane-washed water.The eluates were collected in a separatory funnel containing hexane and hexane-washed water.After shaking and partitioning,the concentrated hexane layer was treated with sulfuric acid and hexane-washed water.The hexane extract was passed through a ?orisil-packed glass column for fractionation.The ?rst fraction eluted with hexane contained HCB,PCB congeners,p,p #-DDE
Table 1
Data of samples collected from the Lake Tai,Shanghai and Hangzhou Bay in China during 2000and 2001Location and Matrix
N Collection date Body length (cm)Body weight (g)Remarks
Lake Tai (No.1)a 33Carp (wild)
3Aug.200016G 0.36136G 18SN:Cyprinus carpio
Topmouth culter 3Aug.200025G 3.6186G 56SN:Erythroculter ilishaeformis Spotted steed 3Aug.200023G 2.7269G 110SN:Hemibarbus maculatus Cat?sh
3Aug.200020G 4.5128G 47SN:unknown
Carp (aquaculture)2Aug.2000n.a.n.a.SN:Cyprinus carpio Shrimp
3Aug.2000n.a.n.a.SN:unknown
Bird (thick-billed reed warbler)3Aug.2000n.a.n.a.SN:Acrocephalus aedon Fish feed-11Aug.2000n.a.n.a.Powder Fish feed-21Aug.2000n.a.n.a.Powder
Sediment-16Aug.
2000
n.a.n.a.One to three kilometers away from western shore of Lake Tai Sediment-21Aug.2000n.a.n.a.Fishpond where is located at 100–150m west of Lake Tai Soil-1
4Aug.2000
n.a.
n.a.
Sesami and bean ?elds
Shanghai (No.2)a 12Sediment-34Apr.2001n.a.n.a.Huangpu River (A tributary of the Chang Jiang River)Sediment-42Apr.2001n.a.n.a.Fishpond Sediment-52Apr.2001n.a.n.a.Creek
Soil-22Apr.2001n.a.n.a.Near the ?sh pond Soil-3
2Apr.
2001
n.a.
n.a.Rice and bean ?elds
Jinshan (Hangzhou Bay,No.3)a 19Bluespotted mudskipper 5Sep.200112.5G 0.7317.3G 2.5SN:Boleophthalmus pectinirostris Silver pomfret
1Sep.200112.274.6SN:Pampus echinogaster Spiny-head croaker 1Sep.200114.131.4SN:Collichthys lucidus Halfsmooth tongue?sh 1Sep.200114.9
13.1SN:Cynoglossus semilaevis Bombay duck 1(2)b Sep.200111.6–16.5 5.9–16.5SN:Harpadon nehereus Trident goby 1Sep.20019.715.4SN:Tridentiger barbatus Redeye mullet 1Sep.200117.143.3SN:Chelon haematocheilus Pike eel 1Sep.200139.361.8SN:Muraenesox cinereus Needle?sh 1Sep.200155.659.5SN:Strongylura anastomella Cutlass ?sh 1Sep.2001n.a.n.a.SN:Trichiurus japonicus File?sh
1Sep.200114.986.5SN:Stephanolepis cirrhifer Mantis shrimp 1
Sep.200110.810.2SN:unknown Shrimp 1(17)b Sep.20010.7–1.0 1.4–1.6SN:unknown
Sediment-62Sep.2001n.a.n.a.Tidal ?at of Hangzhou Bay
Haining (No.4)a 8Crab
2(3)b Sep.2001 5.9G 2.517.1G 10SN:unknown
Sediment-72Sep.2001n.a.n.a.Coastal area of Hangzhou Bay Sediment-82Sep.2001n.a.n.a.Fishpond Soil-4
2Sep.2001n.a.n.a.Rice ?eld
Shaoxing (No.5)a 4Sediment-92Sep.2001n.a.n.a.Coastal area of Hangzhou Bay Soil-5
2
Sep.2001n.a.n.a.Unknown
SN,Scienti?c Name;n.a.,not available.a
Number of locations correspond to those given in Fig.1.b
Number of pooled samples.
417
H.Nakata et al./Environmental Pollution 133(2005)415–429
and trans-nonachlor,while the second fraction eluted with 20%dichloromethane in hexane contained chlor-dane compounds (trans-and cis-nonachlors,and chlor-danes and oxychlordane),p,p #-DDD,p,p #-DDT and HCHs (a -,b -and g -HCH isomers).First fraction was micro-concentrated,and 13C-CB 105was spiked as an injection internal standard.This fraction was injected into GC-MS (Hewlett Packard 6890GC coupled with a 5973mass selective detector)and GC-ECD (Hewlett Packard 6890GC coupled with a 63Ni electron capture detector)for quanti?cation of PCBs and organochlorine pesticides,respectively.The second fraction was micro-concentrated and injected into a GC-ECD for the determination of organochlorine pesticides.The capil-lary columns of GC-MS and GC-ECD were DB-1(J&W Scienti?c Inc.,USA)fused silica capillary column (30m !0.25mm i.d.).The oven temperature was pro-grammed from 70to 160 C at a rate of 10 C/min and held for 10min.Then,the temperature was increased to 260 C at a rate of 2 C/min with a ?nal hold time of 20min.The temperatures of injector and detector were set at 260and 280 C,respectively.Helium and nitrogen were used as carrier and make-up gases,respectively.Individual PCBs were quanti?ed relative to same or similar PCB surrogate standard,therefore PCB concen-trations were automatically corrected for recovery.Recovery percentages of PCB congeners ranged from 83to 104%.In the case of organochlorine pesticides,the recoveries of target analytes through this method ranged from 90to 110%,and their concentrations were not corrected for recovery percentages.A procedural blank was analyzed with every set of six samples to con?rm interfering peaks in chromatograms and to correct sample values,if necessary.The detection limit was
0.04ng/g for DDTs,0.03ng/g for HCHs,0.02ng/g for CHLs,0.01ng/g for HCB and PCBs.
For quality assurance and quality control,our laboratory participated in Inter Laboratory Compari-son Exercise for Persistent Organochlorines in Marine Mammal Tissues,organized by the National Institute of Standards and Technology (NIST)and National Oce-anic and Atmospheric Administration (NOAA).Stan-dard reference material (SRM 1945)was analyzed for selected PCB congeners and organochlorine pesticides.Reliable results were obtained by comparison of generated data from our laboratory with those of standard reference values (Kucklick,2001).2.3.Statistical analysis
To detect the di?erence of OCs concentrations and compositions between samples,the Wilcoxon U -test was employed in this study.Spearman’s rank test was also used to examine a signi?cance of positive correlations.Software from Excel Statistics (Esumi,Tokyo)was used in this study.
3.Results and discussion
OC contaminants were detected in all samples analyzed in this study.In general,DDT and its metabolites were the predominant contaminants in most samples.CHLs and PCBs residues showed a large variation in concentrations between sampling locations,whereas HCH levels in most of samples were lower than those expected.The concentrations of OCs are shown in Tables 2and 3
.
a h g n a h S i a h C n g n a i J g R r
e v i h C t s a E n i a
a
e S s a E t n r e a
n i h C 210°E
23°N
n a H gzh u o y
a B 010km
1
2
3
4
5
T e k a L ai i J ngshan
Ha n i g
n i x o a h S ing
N
03°N
212°E
Fig.1.Map showing sampling sites of sediments,soils and wildlife analyzed in this study.
418H.Nakata et al./Environmental Pollution 133(2005)415–429
3.1.DDT
In Lake Tai,the highest concentrations were found in thick-billed reed warblers collected from Lake Tai (5100G 1700ng/g lipid wt.;Table 2).The DDT level in birds was several times greater than those in ?shes and crustaceans collected in this lake,suggesting the bioaccumulation of DDTs through the food chain of the freshwater ecosystems.Mean concentration of DDTs in ?shes from Lake Tai is less variable among species,ranging from 700ng/g lipid wt.in spotted steeds to 1000ng/g in cat?sh (Table 2).The ratios of p,p #-DDT to P DDTs were generally low (less than 2%)in the lake ?shes and did not di?er among species (Table 2).Total DDT concentrations and the ratios of p,p #-DDT/P
DDTs in shrimp from Lake Tai were 660ng/g lipid wt.and 0.77,respectively,which are almost similar to those observed in ?shes in this lake.
In contrast,large variations in DDT concentrations and compositions were found in marine ?shes collected from Jinshan,Hangzhou Bay (Table 2).Mean concen-tration of DDTs in marine ?shes ranged from 400ng/g lipid wt.in bluespotted mudskipper to 3200ng/g in redeye mullet (Table 2).A high concentration of DDTs was also found in spiny-head croaker (2300ng/g lipid wt.),trident goby (2200ng/g)and pike eel (2200ng/g)collected from Hangzhou Bay (Table 2).These levels were apparently higher than those ?shes from India (mean:625ng/g lipid wt.),Thailand (116ng/g)and Australia (647ng/g)in the 1990s (Kannan et al.,1995).It is interesting to note that p,p #-DDT concentrations in marine ?shes were signi?cantly higher than those in freshwater ?shes (p !0.001),although no statistical di?erence was found in P DDT levels between these groups (p Z 0.481,Fig.2).The ratio of p,p #-DDT to P
DDTs in marine ?shes was 30G 15%,which was approximately 20times greater than those in freshwater ?shes from Lake Tai (1.3G 1.0%;Fig.3).In particular,p,p #-DDT occupied more than 50%of P DDTs in silver pomfret and cutlass ?sh from Hangzhou Bay (Fig.3).Higher concentrations of DDTs were also detected in marine crabs from Haining,Hangzhou Bay (mean:2400ng/g;Table 2).Although the usage of DDT has been banned since 1983in China,these results suggest the presence of local source of DDTs around coastal waters of Hangzhou Bay rather than the inland area of Lake Tai.
Mean concentration of DDTs in farm-raised carp from ?shpond near Lake Tai was 350ng/g lipid wt.(Table 2).This was approximately one third of that in wild carp.We analyzed organochlorines in two di?erent types of ?sh feed used at this pond.DDT concentrations in ?sh feed were very di?erent,with 30ng/g lipid wt.in diet 1and 1100ng/g in diet 2(Table 2).The compositions of DDTs also showed great variations;p,p #-DDD and p,p #-DDE were the major components in diet 1and 2,respectively (Table 2).These ?ndings imply that the composition/ingredients of diets were di?erent,and the less contaminated diet may apply to the cultured ?shes.
As to the DDT residues in sediments,elevated concentrations were found in samples from the Huangpu River,?shpond and a creek around Shanghai city (13–33ng/g dry wt.)and a ?shpond at Haining (57ng/g;Table 2,Fig.4).DDT levels in sediments from Hangzhou Bay and Lake Tai were relatively low,ranging from 0.33to 1.8ng/g dry wt.(Table 2).In general,DDT concentrations in sediments in this study were almost within the range of surface sediment from Pearl River Delta (3.8–31.7ng/g dry wt.;Zhang et al.,2002)and Daya Bay (0.14–20.27ng/g;Zhou et al.,2001)in southeast China.p,p #-DDE and p,p #-DDD collectively accounted for 81G 11%of P DDTs in most sediments in this study,indicating that their parent compound,p,p #-DDT,had been transformed into its metabolites.There are inconsistencies in the results of DDT concentrations between ?sh and sediment samples because DDT levels in marine ?shes were generally higher than those in freshwater samples.While it is di?cult to indicate the reasons for such di?erences,one possibility is to assume that relatively low total organic carbon (TOC)contents in samples may decrease the contaminant concentrations in sediments from Hang-zhou bay.Furthermore,the number of sediment/soil samples analyzed in this study was small,therefore additional research will be needed to evaluate it.
In soils,elevated concentrations of DDTs were found in samples collected around Shanghai and Haining,ranging from 18to 142ng/g dry wt.(mean:67ng/g;Table 2and Fig.4).In general,soils and sediments around a ?shpond showed higher concentrations of DDT,indicating an extensive usage of this pesticide around this area.DDT levels in soils from Lake Tai and Shaoxing were relatively low,less than 10ng/g dry wt.p,p #-DDE was the major component in most soils (47G 20%),followed by p,p #-DDT (38G 23%)and p,p #-DDD (14G 12%),but the proportions showed a large variation among samples.
It is interesting to note that a signi?cant correlation was found between DDT concentrations and organic carbon content in sediment and soils (p !0.01;Fig.5).For the soil–air system in equilibrium,the concentration of a hydrophobic compound is expected to be pro-portional to the organic carbon content in sediments and soils (Kannan et al.,2003).The application rate of pesticide,farm management and physicochemical char-acteristics of sediments and soils,such as amount and type of clay materials,humic acid,pH and temperature,may in?uence the persistence of DDTs in the environ-ment.However,signi?cant correlations between organic carbon and DDTs may imply equilibration of DDTs between soil and organic carbon in this study.
419
H.Nakata et al./Environmental Pollution 133(2005)415–429
It is well known that China is one of the largest producers of organochlorine pesticides.Between the 1950s and 1980s,the total production of DDT was 0.4million tonnes in China,accounting for 20%of the world production (Zhang et al.,2002).Recent inves-tigations on organochlorine pollution around Xiamen Island and Minjian Estuary,southeast China,showed that DDT concentrations in marine ?shes were high,ranging from several hundred ng/g to several m g/g on a wet weight basis,and p,p #-DDT comprised 30–40%of total DDT concentrations (Klumpp et al.,2002).High concentrations of DDTs were also identi?ed in mussels and shell?shes from middle eastern coastal waters in China (2200–29000ng/g lipid wt.:Monirith et al.,2003;34000ng/g:Nakata et al.,2002).Considering these observations and the results in this study,it is probable that DDT is still in use around the coastal waters of China.3.2.HCH
Similar to DDT residues,the highest concentrations of HCHs were found in thick-billed reed warblers from Lake Tai (250G 320ng/g lipid wt.;Table 2).This level was comparable to or higher than those in crows from Japan (110–390ng/g lipid wt.;Kunisue et al.,2003).b -HCH,a persistent isomer of technical HCHs,was the predominant isomer in birds.HCH concentrations in ?shes from Lake Tai were less variable among species,ranging from 64G 16ng/g lipid wt.in carp to 75G 15ng/g in spotted steed (Table 2).The composi-tions of a -,b -and g -HCH to P HCH concentrations in lake ?shes were 9.3–12%,74–85%and 5.7–7.1%,respectively.In shrimp from Lake Tai,mean HCH concentration was 52G 17ng/g lipid wt.b -HCH was the dominant HCH isomer in shrimp (95%of P HCHs;Table 2).
HCH concentrations in marine ?shes from Hangzhou Bay were relatively low,ranging from less than the detection limit in halfsmooth tongue?sh and needle?sh to 38ng/g lipid wt.in bluespotted mudskippers (Table 2).The major HCH residue in marine ?shes was b -HCH,followed by a -HCH,but g -HCH was not detected in most samples.It is worth noting that the ?shes in Lake Tai showed signi?cantly higher concen-trations of HCHs than in marine ?shes from Hangzhou Bay (p !0.001).This suggests the presence of HCH source around Lake Tai (Fig.2).However,HCH levels in ?shes in this study were apparently lower than those reported for ?shes from India (mean:1170ng/g lipid wt.),where technical HCH is still being used (Kannan et al.,1995).
In sediments,high HCH concentrations were found at a creek (2.7G 0.82ng/g dry wt.)and Huangpu River (1.2G 0.36ng/g)near Shanghai city and ?shpond at Haining (2.4G 0.18ng/g)(Fig.4and Table 2).The
S e d i m e n t -7(c o a s t a l a r e a o f H a n g z h o u B a y )2
0.86G 0.01
0.10G 0.070.12G 0.04
0.10G 0.01
0.33G 0.10
0.05G 0.01
0.06G 0.01
!0.03
0.11G 0.01
S e d i m e n t -8(?s h p o n d )24.3G 3.231G 0.9822G 0.523.5G 2.157G 0.590.62G 0.011.6G 0.150.16G 0.012.4G 0.18S o i l -4(p a d d y ?e l d )
2
2.8G 2.1
31G 2312G 5.0
40G 56
83G 83
0.08G 0.06
0.59G 0.46
0.04G 0.01
0.71G 0.53
S h a o x i n g (N o .5)a
4S e d i m e n t -9(C o a s t a l a r e a o f H a n g z h o u B a y )2
1.0G 0.10.11G 0.090.13G 0.03
0.11G 0.02
0.36G 0.130.06G 0.010.14G 0.04!0.030.20G 0.05
S o i l -5(p a d d y ?e l d )
21.3G 0.60.45G 0.350.06G 0.010.20G 0.030.70G 0.39
!0.03!0.03!0.03!0.03
C o n c e n t r a t i o n u n i t s :S e d i m e n t a n d s o i l s [n g /g d r y w t .],B i o l o g i c a l s a m p l e s i n c l u d i n g ?s h d i e t s [n g /g l i p i d w t .].a N u m b e r o f l o c a t i o n s c o r r e s p o n d t o t h o s e g i v e n i n F i g .1.b N u m b e r o f p o o l e d s a m p l e s .
421
H.Nakata et al./Environmental Pollution 133(2005)415–429
Table3
Concentrations(ng/g)of seven organochlorines in sediments,soils,?shes,?sh diets,crustaceans and birds collected in China during2000and2001
Location and Matrix N Oxychlordane trans-
Chlordane cis-
Chlordane
trans-
Nonachlor
cis-
Nonachlor
P
CHLs HCB
P
PCBs
Lake Tai(No.1)a33
Carp(wild)3 2.8G1.331G1140G1222G9.013G8.4110G2923G14280G240 Topmouth culter3 4.7G3.1120G110180G17052G3921G11380G33037G32160G26 Spotted steed3 6.1G3.637G7.568G2430G8.011G2.0150G4420G14110G26 Cat?sh3 5.7G2.642G1367G3029G1516G8.5160G6922G9.8180G71 Carp(?shpond)20.56G0.078.1G0.708.3G1.0 3.0G2.2 1.2G0.3021G0.1414G3.614G3.4 Shrimp3(15)b17G4.9 2.4G0.78 5.6G3.628G11 4.6G2.358G1111G0.6060G4.4 Bird(thick-billed
reed warbler)
314G150.57G0.160.73G0.54 3.2G1.2 1.4G2.020G1932G23150G110 Fish feed-11!0.02 5.5 4.9!0.02!0.021013!0.01 Fish feed-21 1.83231127.5855174 Sediment-1(Lake Tai)6!0.020.05G0.020.05G0.020.03G0.010.03G0.020.16G0.050.08G0.05!0.01 Sediment-2(?shpond
nearby Lake Tai)
1!0.02!0.020.030.03!0.020.06!0.01!0.01
Soil-1(Sesami and
bean?eld)
4!0.020.04G0.01!0.02!0.02!0.020.04G0.010.08G0.02!0.01
Shanghai(No.2)a12
Sediment-3(Huangpu
River)
4!0.02!0.02!0.02!0.02!0.02!0.02 3.2G1.60.57G0.53
Sediment-4(?shpond)2!0.02!0.02!0.02!0.02!0.02!0.020.16G0.070.05G0.01 Sediment-5(creek nearby a
rice?eld)
2!0.02!0.02!0.02!0.02!0.02!0.02 1.1G0.810.75G0.01
Soil-2(nearby a?shpond)2!0.02!0.02!0.02!0.02!0.02!0.02 3.2G1.10.41G0.20 Soil-3
(rice and bean?eld)
2!0.02!0.02!0.02!0.02!0.02!0.020.61G0.240.62G0.32
Jinshan
(Hangzhou Bay,No.3)a
19
Bluespotted mudskipper5 1.7G0.59 1.9G0.50 5.1G2.2 4.0G2.5 1.7G0.9414G6.719G6.414G6.6 Silver pomfret1!0.02 1.1 2.0 6.7 1.611 3.5109
Spiny-head croaker1128.911 6.6 5.04328170 Halfsmooth tongue?sh1!0.02!0.02!0.02!0.02!0.02!0.02!0.01140 Bombay duck1(2)b 5.2 5.67.9 5.9 4.4298.7160 Trident goby1 6.5!0.02 4.77.4 1.9201579 Redeye mullet1 5.21020219.96761110
Pike eel1 6.3 4.916218.35722180 Needle?sh1!0.02!0.02!0.02!0.02!0.02!0.027.459 Cutlass?sh1!0.02 1.5 2.8 2.7 2.39.3 2.127
File?sh1 1.9 1.5 3.0 3.7 1.211117.3
Mantis shrimp1!0.02!0.02 6.07.1!0.02137.0280 Shrimp1(17)b24!0.021213 6.45513130 Sediment-6(tidal?at
of Hangzhou Bay)
2!0.02!0.02!0.02!0.02!0.02!0.020.50G0.06!0.01
Haining(No.4)a8
Crab2(3)b28G21 4.6G6.515G1319G4.5 3.8G5.471G2736G11230G55 Sediment-7(coastal area
of Hangzhou Bay)
2!0.02!0.02!0.02!0.02!0.02!0.020.10G0.05!0.01 Sediment-8(?shpond)2!0.02!0.02!0.02!0.02!0.02!0.020.20G0.06!0.01
Soil-4(paddy?eld)2!0.02!0.02!0.02!0.02!0.02!0.020.11G0.090.05G0.01 Shaoxing(No.5)a4
Sediment-9(coastal area
of Hangzhou Bay)
2!0.02!0.02!0.02!0.02!0.02!0.020.14G0.06!0.01
Soil-5(paddy?eld)2!0.02!0.02!0.02!0.02!0.02!0.020.08G0.01!0.01 Concentration units:Sediment and soils[ng/g dry wt.],Biological samples including?sh diets[ng/g lipid wt.].
a Number of locations correspond to those given in Fig.1.
b Number of pooled samples.
422H.Nakata et al./Environmental Pollution133(2005)415–429
levels of HCHs at Lake Tai and Hangzhou Bay were generally low,between 0.43G 0.11and 0.25G 0.08ng/g dry wt.,respectively (Table 2).HCH concentrations in ?shpond sediments near Lake Tai were less than the detection limit,implying a small amount of usage and/or the rapid degradation of this pesticide.The concentra-tion range of HCHs in sediments was comparable to or higher than those reported in Xiamen Harbor (!0.01–0.14ng/g dry wt.;Zhou et al.,2000)and Daya Bay (0.32–4.16ng/g;Zhou et al.,2001),but several orders of magnitude lower than those found in Pearl River Estuary (42–101ng/g;Wu et al.,1999)in China.b -HCH was the major isomer in all the sediments analyzed (68G 8.7%of P HCHs),followed by a -(27G 9.8%)and g -(5.2G 4.5%)isomers,but g -HCH was not detected in any marine sediments.
In soil samples,concentrations of HCHs ranged from less than the detection limit (!0.03ng/g)at Shaoxing to 2.4G 0.72ng/g at a rice and bean ?eld in Shanghai,with a mean concentration of 1.0ng/g (Table 2and Fig.4).These levels were apparently lower than those found in cultivated soils collected in 1981(740ng/g dry wt.;Huang,1989)and in greenhouse soils from Beijing suburbs (11.64–29.8ng/g dry wt.;Ma et al.,2003).
DDTs 1
1,000
p,p’-DDT HCHs CHLs HCB PCBs
Concentration (ng/g lipid wt.)
**: p <0.001*: p <0.005
https://www.doczj.com/doc/b415376857.html,parison of organochlorine concentrations in ?shes collected from freshwater (Lake Tai;closed circles)and marine (Hangzhou Bay;open circles)environments.**p !0.001,*p !0.005.
p,p'-DDE
Bluespotter mudskipper
Silver pomfret Spiny-head croaker Halfsmooth tonguefish
Bombay-duck Trident goby Redeye mullet
Pike ell Needlefish Cutlass fish
Filefish
Carp
Topmouth culter Spotted steed
Catfish
FRESHWATER FISH
MARINE FISH
p,p'-DDD p,p'-DDT
Composition (%)
https://www.doczj.com/doc/b415376857.html,parison of DDT compositions in ?shes collected from freshwater (Lake Tai)and marine (Hangzhou Bay)environments.
423
H.Nakata et al./Environmental Pollution 133(2005)415–429
b -HCH was the dominant isomer in all soils analyzed in this study.
Recently,the record of technical HCHs usage in China has been documented.The area of the highest usage of technical HCH in China was Jiangsu Province (Li et al.,2001),and Lake Tai is located in this province.The amount of HCH usage in Jiangsu Province is was as high as 500kt during 1952and 1984(Li et al.,2001),which is greater than the amount used in Japan during 1950–1970(400kt;Tatsukawa et al.,1972).It is reported that lindane (g -HCH)is being used in China even now (Li et al.,2001).However,in general,HCH concen-trations in organisms,sediments and soils analyzed in this study were not so high.Also,b -HCH was the dominant isomer in most sediment and soil samples.These observations may suggest the lack of new input of HCHs into soil and sediment around middle eastern China.Relatively high concentrations of HCHs in ?shes at Lake Tai may indicate past extensive use of this pesticide around this region.The mean concentration of a -and g -HCH in the air at Lake Tai was generally low (74pg/m 3for a -HCH and 46pg/m 3for g -HCH),in-dicating that the use of technical HCH and g -HCH is low (Qui et al.,2004).The residue levels of HCHs in Chinese foodstu?s obtained during 2000–2001have drastically decreased during the last 20years (Nakata et al.,2002).
Shanghai Jingshang Haining Shaoxing Lake Tai
Shanghai
Haining
Shaoxing
Lake Tai
Concentration (ng/g dry wt.)
Fig.4.Concentrations of DDTs and HCHs in sediments and soils in China.
50
100
150
C o n c e n t r a t i o n (n g /g d r y w t .)
Total organic carbon (%)
Fig.5.Correlation between DDT concentrations and organic carbon contents in sediments and soils from China.
424H.Nakata et al./Environmental Pollution 133(2005)415–429
3.3.CHLs
Regarding chlordane compounds,the highest con-centration was found in topmouth culter (380ng/g lipid wt.)from Lake Tai,followed by other freshwater ?shes (100–160ng/g)and shrimp (58ng/g)(Table 3).The thick-billed reed warblers contained lower CHL levels (20G 19ng/g lipid wt.)than ?sh species in Lake Tai.Mean CHL concentration in lake ?shes was 200ng/g lipid wt.,which is greater than those observed for ?shes from India (100ng/g),Vietnam (49ng/g),Indonesia (54ng/g),but lower than in Australia (1500ng/g)(Kannan et al.,1995).The major components of CHLs were cis -and trans -chlordanes in all ?shes from Lake Tai,accounting for 42and 28%of P CHL concen-trations,respectively (Table 3and Fig.6).CHL concentration in carp collected from the ?shpond near Lake Tai was 5–10times lower than those in wild freshwater ?shes.This implies the use of ?sh feed that contain a low concentration of CHLs.
Concentrations of CHLs in marine organisms from Hangzhou Bay were generally low,ranging from less than the detection limit in tongue?sh and needle?sh to 71ng/g lipid wt.in crabs (mean concentration:21ng/g;Table 3).The dominant CHL compounds in marine ?shes was trans -nonachlor and cis -chlordane,accounting for 32and 27%of P CHL concentration,respectively (Fig.6).Signi?cantly higher CHL concentrations in ?shes at Lake Tai than those from Hangzhou Bay indicate the presence of local source around Lake Tai (Fig.2).
It was reported that cis -chlordane accumulates preferentially to the trans -chlordane in channel cat?sh under laboratory exposures,indicating faster metabo-lism and/or excretion of the trans isomer (Marphy and Gooch,1995).It is known that oxychlordane is one of the metabolites of technical CHLs in organisms,and the OXY/P
CHLs ratio is a useful indicator for under-standing CHL metabolism (Kawano et al.,1988;Dearth and Hites,1991).In the present study,the ratio of trans -chlordane to P CHLs (T-CA/P CHLs)was 28%in freshwater ?shes from Lake Tai,which is apparently greater than those in marine ?shes (12%;Fig.6).Furthermore,the ratio of oxychlordane to P CHLs (OXY/P
CHLs)in freshwater ?shes was signi?cantly lower than that in marine ?shes (freshwater:3%;marine water:13%).High T-CA/P CHLs and low OXY/P CHLs ratios in freshwater ?shes rather than in marine ?shes imply a recent exposure to technical CHLs of ?shes at Lake Tai.
In sediments and soils,CHLs were only detected in samples from Lake Tai,with concentrations of 0.04G 0.01ng/g dry wt.in soils and 0.16G 0.05ng/g in sediments.trans -and cis -chlordanes were the major components in most of these samples,and oxychlordane was not detected.CHL levels in sediments and soils from marine and terrestrial environments at Hangzhou Bay and Shanghai region were all less than the detection limit (!0.02ng/g).High concentrations of CHLs in sediments at Lake Tai rather than those at coastal waters were similar to that observed for ?shes.
It has been reported that CHLs are still being extensively used in China against termites (Xu et al.,2004).The Lake Tai region is one of the most densely populated areas in China;it accounts for 0.4%of the
FRESHWATER FISH
:trans -CHL :cis -CHL :trans -NONA
:cis -NONA : Oxy CHL
Composition (%)
https://www.doczj.com/doc/b415376857.html,parison of CHLs compositions in ?shes collected from freshwater (Lake Tai)and marine (Hangzhou Bay)environments.trans -CHL,
trans -chlordane;cis -CHL,cis -chlordane;trans -NONA,trans -nonachlor;cis -NONA,cis -nonachlor;oxy CHL,oxychlordane.
425
H.Nakata et al./Environmental Pollution 133(2005)415–429
total area of China and2.9%of the nation’s population, and it provides more than14%of the nation’s gross domestic product(GDP)(Shen et al.,2000).These facts indicate that the use of CHLs for human and industrial activities may be considerable.
3.4.HCB
Mean concentrations of HCB in?shes and birds from Lake Tai were relatively consistent,ranging from20ng/ g lipid wt.in spotted steed to37ng/g in topmouth culter.HCB levels in shrimp and farm-raised carp around Lake Tai were relatively low(11–14ng/g lipid wt.),which is similar to those observed for HCH and CHL residues in these species.In marine?shes,HCB levels ranged from the detection limit in halfsmooth tongue?sh to61ng/g lipid wt.in trident goby,with a mean concentration of16ng/g.No signi?cant di?erence in HCB concentrations was observed between ?shes from Lake Tai and Hangzhou Bay(Fig.2).In general,mean HCB levels of?shes in this study were higher than those in?shes from other Asian countries, such as India,Thailand,Vietnam and Indonesia (!5.0ng/g lipid wt.),but lower than in?shes from Australia(123ng/g lipid wt.;Kannan et al.,1995).
In sediments,high concentrations of HCB were detected in samples from the Huangpu River (3.2G1.6ng/g dry wt.)and a creek(1.1G0.81ng/g) near Shanghai.The sediments at Lake Tai,Hangzhou Bay and?shpond at Haining contained relatively low HCB residues,ranging from0.08ng/g dry wt.to 0.20ng/g.Regarding soil samples,the highest concen-trations of HCB were found in samples collected from a?shpond near Shanghai(3.2G1.1ng/g dry wt.).However,HCB levels in all soils except the above samples were generally low.
Although little information is available on the contamination of HCB in China,it was reported that HCB is still being produced in a chemical factory near Ya-Er Lake in China(Wu et al.,1997).HCB concen-trations in sediments and soils near this lake were extremely high(several thousand m g/g dry wt.),suggest-ing serious pollution by this compound(Wu et al., 1999).Relatively high HCB residues were determined in tea leaves obtained from Shanghai(Nakata et al.,2002) and human milk from Dalian and Shenyang,northeast China(Kunisue et al.,2004).HCB in pine needles in China is higher than that in European countries(Xu et al.,2004).These facts suggest the possibility of a recent use of HCB in China,while the total amount of application may be small.
3.5.PCBs
In Lake Tai,higher concentrations of PCBs were found in carp(280ng/g lipid wt.),followed by other freshwater?shes(110–180ng/g),birds(150ng/g)and shrimp(60ng/g)(Table3).PCB residues were appar-ently low in carp from the?shpond(14G3.4ng/g) compared to those in Lake Tai,suggesting the use of?sh feed with less contamination of PCBs.On the other hand,PCB levels in marine organisms from Hangzhou Bay were relatively low,and showed a large variation between species(Table3).The concentrations ranged from7.3ng/g lipid wt.in?le?sh and280ng/g in mantis shrimp,with a mean and standard deviation of 93G74ng/g in marine organisms.The bluespotted mudskipper showed lower concentrations of PCBs (14G6.6ng/g lipid wt.)than those in other marine
FRESHWATER FISH
MARINE FISH
Composition (%)
: 3Cl: 4Cl : 5Cl : 6Cl: 7Cl: 8Cl
https://www.doczj.com/doc/b415376857.html,parison of PCBs compositions in?shes collected from freshwater(Lake Tai)and marine(Hangzhou Bay)environments. 426H.Nakata et al./Environmental Pollution133(2005)415–429
?shes,and these levels were 1–2orders of magnitude lower than those of same species in the Ariake Sea,Japan (Nakata et al.,2003).Similar to HCH and CHL concentrations,PCB levels in freshwater ?shes from Lake Tai were signi?cantly higher than those in Hangzhou Bay (p !0.005;Fig.2).This indicates the presence of local source of PCBs in Lake Tai.
PCB compositions in ?shes from Lake Tai were relatively consistent,and penta-and hexa-chlorinated congeners were dominant,followed by tetra-and hepta-chlorinated biphenyls (Fig.7).PCB congeners CB-153,-138,-118and -101were the prevalent congeners in lake ?shes,accounting for 9.7–21%,10–18%,7.5–14%and 4.5–7.3%of the total PCB con-centrations,respectively (Fig.8).In contrast,only a few PCB congeners were found in shrimp and birds in Lake Tai (Fig.8).While the major congeners in shrimp and birds were almost the same as in lake ?shes,the levels of tri-and tetra-chlorobiphenyls were signi?cantly lower in shrimp/birds than in ?shes.These results
050
100
050
100
050
100
R e l a t i v e c o n c e n t r a t i o n
050
100
050
100
50
100
28+3549+64441+658+77691+91084+92+910997+1187+11811101513144+141312151413171817171817202019196+2019193Cl
4Cl 5Cl 6Cl 7Cl 8Cl
Fig.8.Relative isomers/congeners compositions of PCBs in ?shes,shrimps and birds collected from Lake Tai,China.Vertical bars represent concentrations of individual congeners relative to the most major congener (IUPAC 153),which was treated as 100.
427
H.Nakata et al./Environmental Pollution 133(2005)415–429
indicate the metabolism of lower chlorinated PCB congeners in shrimp and bird.
PCB compositions in marine ?shes showed the prevalence of hexa-congeners,although a large variation was found between species (Fig.7).A higher proportion of tri-chlorinated congeners was found in halfsmooth tongue?sh,accounting for 57%of P
PCBs.In Bombay duck,hepta-CB congeners occupied 38%of P https://www.doczj.com/doc/b415376857.html,parison of PCB compositions between freshwater and marine ?shes indicated that tri-,hepta-and octa-chlorinated congeners were dominant in marine ?shes,whereas freshwater ?shes contained a greater percentage of tetra-CBs than marine ?shes.These results may indicate the di?erent sources of technical PCBs between marine and freshwater environments.
Sediments and soils collected around Shanghai con-tained relatively higher concentrations of PCBs,with mean levels of 0.46ng/g dry wt.in sediments and 0.51ng/g in soils.In general,low concentrations of PCBs were found in sediments and soils from Lake Tai,Hangzhou Bay and Haining.These results imply the presence of PCB sources in urban and industrialized areas in China.Hexachlorobiphenyls were the prevalent congeners in sediments and soils,accounting for 69and 80%of the P
PCBs,respectively.CB-138,-153and -144C 149were the major congeners in sediments and soils.
It has been reported that approximately 10000tonnes of PCBs have been produced in China during 1965and 1974(Qin et al.,2003).The domestic products of technical PCBs in China are named PCB 3and PCB 5,and their compositions are almost similar to those of Aroclor 1242and 1254,respectively (Jiang et al.,1997).Most of these products had been used as dielectric ?uids in capacitors (Jiang et al.,1997).
The presence of higher proportions of penta-and hexa-PCB congeners in lake ?shes may suggest the use of a highly chlorinated PCB product,such as PCB 5,around Lake Tai.On the other hand,the variable compositions of PCBs in marine ?shes imply that there are di?erent sources of PCB inputs into the coastal waters around Hangzhou Bay.However,PCB levels in ?shes and birds were generally low when compared with those in other countries (Kannan et al.,1995;Kunisue et al.,2003).PCB concentrations were also low in mussels,foodstu?s and human tissues collected from China (Nakata et al.,2002;Monirith et al.,2003;Kunisue et al.,in press ).These observations indicate that the amount of usage of PCBs may be small in China,while the local source of this contaminant is present around Lake Tai.
4.Conclusions
In this study,we determined concentrations of organochlorines,such as DDTs,HCHs,CHLs,HCB
and PCBs,in sediments,soils and wildlife collected from Lake Tai,Hangzhou Bay,and the Shanghai city region in China.The results indicated that DDT was the major contaminant in most samples analyzed in this study.Although the use of DDT was o?cially banned in China more than 20years ago,the concentrations and compositions in ?shes suggest fresh input of this pesticide into the coastal environment around Hangzhou Bay.HCH,CHL and PCB concentrations in Chinese ?shes imply the presence of local sources of these contaminants in freshwater environment around Lake Tai.However,these levels were comparable to or lower than those ?shes from other Asian and Oceanian countries.Considering these observations,further investigations on the moni-toring of DDT pollution are needed to assess the risks of wildlife and human health in China.
Acknowledgements
We sincerely thank Professor K.Kannan (Wads-worth Center,New York State Department of Health,State University of New York at Albany)for critical reading of the manuscript and making a number of helpful suggestions.We wish to thank Dr.Kim,E-Y.(Ehime University,Japan)for assistance determining bird,species,and the sta?in China and Japan for their cooperation in collecting samples.This research was partly supported by the grant-in-aid (no.13027101)for Scienti?c Research on Priority Area (A)(Contamination and Risk Assessment of Endocrine Disrupters in Wildlife)from the Ministry of Education,Culture,Sports,Science,and Technology of Japan and a Grant-in-aid for Joint Research Project under the Japan–China Cooperation Program.
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