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1.
This study reports the levels and distribution patterns of some organochlorine pesticides (OCPs) in fish samples of the Gomti
river, India, collected from three sites. In the fish muscles ∑OCPs ranged between 2.58–22.56 ng g−1 (mean value: 9.66 ± 5.60 ng g−1). Neither spatial nor temporal trends could be observed in distribution of the OCPs. Aldrin was the predominant OCP, whereas,
HCB and methoxychlor could not be detected. α-HCH and β-HCH among the isomers of HCH and pp-DDE among the metabolites of DDT
were the most frequently detected OCPs. The results revealed that the fish of the Gomti river are contaminated with various
OCPs. 相似文献
2.
Tang Z Yang Z Shen Z Niu J Liao R 《Archives of environmental contamination and toxicology》2007,53(3):303-312
Residues of hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) and their environmental risks in surface
sediments collected from the rivers and lakes in Yangtze River Catchment of Wuhan, China, are investigated in this paper.
Based on dry weight (dw), the concentrations of ΣHCH (α-, β-, and γ-HCH) and ΣDDT (p p′-DDT, o p′-DDT, p p′-DDE, p p′-DDD) in sediments ranged from 0.10 to 21.10 ng g−1 (mean, 4.03 ng g−1 dw) and 0.79 to 35.61 ng g−1 dw (average, 6.93 ng g−1 dw), respectively. Compared with some published guideline values of organochlorine pesticides (OCPs) in sediments, the concentrations
of HCHs were at safe levels while the DDT residues would pose adverse biological effects in this studied catchment. The distribution
of OCPs in sediments indicated that the input of tributaries was an important factor for OCP residues in the mainstream of
the Yangtze River. Levels of OCPs in the sediments were influenced by total organic carbon contents, clay contents, water
contents, and pH values of sediments. The present study suggested that historical usage of technical HCH and DDT was the main
reason for OCP residues in the sediments from both rivers and lakes. Furthermore, the composition of OCPs reflected additional
sources of the holding usage of lindane and fresh inputs of dicofol mixture in this region. 相似文献
3.
Sarkar SK Binelli A Riva C Parolini M Chatterjee M Bhattacharya AK Bhattacharya BD Satpathy KK 《Archives of environmental contamination and toxicology》2008,55(3):358-371
This paper presents the first comprehensive report of the organochlorine pesticide residues (OCs) such as hexachlorocyclohexane
isomers (HCHs), dichlorodiphenyltrichloroethane and its six metabolites (DDTs), and hexachlorobenzene (HCB) in core sediments
(<63-μm particle size) from the Indian Sunderban wetland. The pooled mean values of the mass fraction of ΣHCHs, HCB, and ΣDDTs
in the sediments were 0.05–12, 0.05–1.4, and 0.05–11.5 ng g−1 dry weight, respectively. The vertical distribution of pesticides reveals an erratic pattern. The concentration of four isomers
of HCHs reveals a heterogenic distribution where γ-HCH (lindane) and β-HCH shared the dominant part. The mass fraction of
HCB did not show any sharp spatial variation. The prevailing sequence of DDT metabolites indicates an active degradation of
the parent compound in the sediments and/or inputs of already degraded pp’DDT to the region. Peak concentrations of HCH isomers
and DDT metabolites have the potential to induce ecotoxicological impact as per the sediment quality guidelines. 相似文献
4.
Vu Duc Toan 《Bulletin of environmental contamination and toxicology》2013,90(1):132-135
This work investigated the contamination status of selected organochlorine pesticides (OCPs: p,p′-DDT, p,p′-DDE, p,p′-DDD, α, β, γ, δ-HCH) in sediment of the CauBay river. Wide occurrence and remarkable residue levels of these two OCPs have been found in the study areas. ΣDDT concentrations ranged from 51.84 to 92.76 ng.g?1 dry weight, whereas ΣHCH concentrations ranged from 4.56 to 11.39 ng g?1 dry weight. All of the sampling sites exceeded the effects range median levels for DDT (>46.1 ng g?1). The analyzed results show that ΣDDT and ΣHCH displayed uniform high and low distribution, respectively. There is no recent input of DDT and HCH in the study area. 相似文献
5.
Contamination by Selected Organochlorine Pesticides (OCPs) in Surface Soils in Hanoi, Vietnam 总被引:2,自引:0,他引:2
Toan VD Thao VD Walder J Schmutz HR Ha CT 《Bulletin of environmental contamination and toxicology》2007,78(3-4):195-200
An evaluation of selected organochlorine pesticide residues [p,p′- dichlorodiphenyltrichloroethane (DDT), p,p′- dichlorodiphenyldichloroethylene (DDE), p,p′- dichlorodiphenyldichloroethane (DDD), α, β, γ and δ- hexachlorocyclohexane (HCH)] in the surface soils of Hanoi, Vietnam
was carried out. Sixty representative soil samples were collected from the centre of Hanoi and five surrounding districts.
In agricultural areas, ΣDDT concentrations ranged from < 0.02 to 171.83 ng g−1 (mean 89.86 ng g−1) dry weight, whereas ΣHCH concentrations ranged from < 0.05 to 20.57 ng g−1 (mean 8.03 ng g−1) dry weight. Investigation of the ratio of different isomers in the soil samples indicates that there has been no recent
input of DDT and HCH in the study area. 相似文献
6.
Organochlorine Pesticide and Polychlorinated Biphenyl in Feathers of Resident and Migratory Birds of South-West Iran 总被引:2,自引:0,他引:2
Behrooz RD Esmaili-Sari A Ghasempouri SM Bahramifar N Hosseini SM 《Archives of environmental contamination and toxicology》2009,56(4):803-810
Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene
(HCB), α-, β-, and γ-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos.
28, 52, 101, 138, 153, and 180) were determined in tail feathers from 35 birds belonging to 15 species, all originating from
the southwest of Iran (Khuzestan, coast of the Persian Gulf) and kept in museum collections. The patterns of organochlorine
contaminants (OCs) in birds varied depending on their migratory behavior. Resident birds contained higher median PCB concentrations
(<LOQ-151 ng/g feather) than HCHs, DDTs, and HCB. Locally migrating birds had higher median concentrations of HCHs (19–83 ng/g
feather). In contrast, long-distance migrants had lower concentrations of HCB and HCHs. A positive correlation was observed
among OCs in these birds, suggesting that trophic level, feeding strategy, and taxonomic group are influencing factors for
the OC concentrations in bird feathers. An estimate of the risk associated suggests that levels of OCPs and PCBs were lower
or close to the threshold reported to affect reproduction in 1990s. 相似文献
7.
Wenyou Hu Tieyu Wang Jong Seong Khim Wei Luo Wentao Jiao Yonglong Lu Jonathan E. Naile Chunli Chen Xiang Zhang John P. Giesy 《Archives of environmental contamination and toxicology》2010,59(1):71-79
Residues of organochlorine pesticides (OCPs), hexachlorocyclohexanes (HCHs), and dichlorodiphenyltrichloroethanes (DDTs) and
their environmental risks in surface sediments collected from marine and adjacent riverine/estuarine areas in the northern
Bohai Sea, China, were investigated. Concentrations of ΣHCH and ΣDDT in sediments ranged from below detection (<LOD) to 1964.97 ng g−1 dry wt (dw; mean, 92.51 ng g−1 dw) and <LOD to 86.46 ng g−1 dw (mean, 9.23 ng g−1 dw), respectively. Concentrations of HCH and DDT were generally higher in marine than riverine sediments. Concentrations
of HCH and DDT residues found in the present study were higher than those reported in marine and river/estuary sediments from
other areas of the world. The source of HCH in sediments could be explained by the large amount of historical use, while DDT
seemed to be a combination of erosion of the weathered soils and long-range atmospheric transport. Concentrations of HCH in
sediments from the study areas did not exceed sediment quality guidelines (SQGs), with the exception of γ-HCH. However, risks
posed by concentrations of DDT observed in sediments were found to be moderate to high compared with those posed by consensus-based
SQGs. Although the mean sedimentary concentrations of HCH and DDT found in the area of the northern Bohai Sea, China were
lower than suggested SQGs in general, their concentrations in some locations were close to or above the SQGs for adverse effects
in benthic organisms and, thus, remain a cause for concern. 相似文献
8.
Distribution and Potential Human Risk of Organochlorine Pesticides in Market Mollusks from Dalian, China 总被引:2,自引:0,他引:2
Hongliang Jia Yaqing Chang Yeqing Sun Degao Wang Xianjie Liu Meng Yang Diandou Xu Bo Meng Yi-Fan Li 《Bulletin of environmental contamination and toxicology》2010,84(3):278-284
Levels of organochlorine pesticides (OCPs) were analyzed in mollusk samples collected from markets in Dalian, China. Among
14 OCPs screened, chlordane (Chls), dichlorodiphenyltrichloroethane (DDT) and 1,2,3,4,5,6-hexachlorocyclohexane (HCH) were
dominant compounds with the medians of 30.2, 5.31 and 2.03 ng/g wet weight (ww), respectively. Source analysis showed that,
much higher concentrations of Chls in mollusk samples were the result of usage of the chemical in the city, HCH in samples
were mainly due to historical technical HCH usage, and a small amount of fresh use of DDT might exist, causing high portion
of p,p′-DDT in samples. Cumulative distribution functions for the concentrations of the selected OCPs were compared to several threshold
criteria, indicating that concentrations in most mollusk samples were lower than the safe lines. The concentration data of
selected OCPs were used for risk assessment, and human exposure levels were compared to noncancer and cancer benchmarks. 相似文献
9.
Hu W Huang B Zhao Y Sun W Gu Z 《Bulletin of environmental contamination and toxicology》2011,87(5):561-566
Residues of organochlorine pesticides (OCPs), dichlorodiphenyltrichloroethane (DDT) and hexachlorocyclohexane (HCH), their
risks and affecting factors in 544 representative soils collected from a typical alluvial plain of the Yangtze River Delta
region, China, were investigated. Mean concentrations of ΣDDT and ΣHCH in soils were 88.8 and 99 ng/g, respectively. Historical
application of DDT and HCH were the major sources of their residues in soils. Concentrations of DDT in soils had relative
greater levels of contamination, while concentrations of HCH were almost at safe levels. Residues of DDT and HCH in soils
were affected by soil types as well as soil textures. 相似文献
10.
Distribution of HCHs and DDTs in Soils from Beijing City, China 总被引:13,自引:0,他引:13
Li X Zhu Y Liu X Fu S Xu X Cheng H 《Archives of environmental contamination and toxicology》2006,51(3):329-336
Concentrations of HCH isomers, DDT, and its metabolites have been measured in 63 soil samples collected in the urban area
and outskirts of Beijing City. HCHs and DDTs were observed in all samples and their geometric mean levels were 5.78 and 38.21
ng g−1, respectively. The spatial distribution of OCPs in Beijing was clearly showed by the contour map, suggesting the sites with
the higher level of OCPs are located in the west and the south region and urban areas within the study regions.” Furthermore,
a t-test showed a significant difference of the level of some compounds between urban and outskirts areas. The temporal distribution
of HCHs and DDTs suggested that the historical application of OCPs has a great effect on the residual level. The ratios of
(α-/γ -HCH (p,p’-DDE+p,p’-DDD)/p,p’-DDT, and o,p’-DDT/p,p’-DDT indicated the present of lindane and impure dicofol besides
technical HCHs and technical DDTs in Beijing. The potential risk of HCHs and DDTs was assessed on the basis of some current
guideline values for soil. The level of OCPs in our study area was compared with other studies. 相似文献
11.
Chunnian Da Ke Wu Jie Jin Minjun Yu 《Bulletin of environmental contamination and toxicology》2017,98(6):784-790
Twenty-two organochlorine pesticides (OCPs) were investigated in Anhui reach of Huaihe river, China. Seventeen out of 22 OCPs were detected by GC-MS. The mean concentrations of OCPs followed the order: HCHs?>?DDTs?>?HCB?>?chlordanes?>?endosulfans. Levels of total HCHs and total DDTs ranged from 2.54 to 13.91 ng g?1 (mean?=?7.52 ng g?1) and 0.016 to 2.54 ng g?1 (mean?=?0.45 ng g?1), respectively. The concentrations of DDTs were lower than those of HCHs. Compared with the other rivers in China, DDTs and HCHs were relatively lower or similar. Statistical analysis indicated that the OCPs concentration differences were not insignificant between upstream, midstream and downstream. The compound compositions suggested that historical usage of lindane and fresh DDT were the main sources. The regression analysis indicated that TOC has influence on the levels of HCHs and little influence on the levels of DDTs in the sediments. 相似文献
12.
Darija Ko?ul Snje?ana Herceg Romani? Zorana Kljakovi?-Ga?pi? Jere Ve?a 《Bulletin of environmental contamination and toxicology》2009,83(6):880-884
The distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was investigated in Mediterranean
blue mussel collected at four locations in Mali Ston Bay few times a year in 2005–2007. OCPs were found in all samples and
levels ranged between 0.07 and 7.58 ng g−1 dry wt. Levels of PCBs ranged between 0 (below detection limit) and 21.55 ng g−1 dry wt. For most analyzed compounds there were no significant level changes between the 3 years. Exceptions are decreased
levels of β-HCH, DDD, and PCB-138 and increased levels of γ-HCH and DDT in 2007. However, mussels from this area are applicable
for human diet. 相似文献
13.
Concentrations and Accumulation Features of Organochlorine Pesticides in the Baiyangdian Lake Freshwater Food Web of North China 总被引:3,自引:0,他引:3
Guocheng Hu Jiayin Dai Bixian Mai Xiaojun Luo Hong Cao Jianshe Wang Fengchao Li Muqi Xu 《Archives of environmental contamination and toxicology》2010,58(3):700-710
Organochlorine pesticides (OCPs), such as hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT), are ubiquitous
anthropogenic environmental contaminants. They are persistent, broad-spectrum toxicants that accumulate in the food web with
potential risks to the ecosystem and human health. HCHs were the predominant contaminants in Baiyangdian Lake, North China.
Concentrations of HCHs and DDTs ranged from 58 to 563 ng/g lipid weight (lw) and 21 to 401 ng/g lw, respectively, for aquatic
biota samples. The highest levels of HCHs and DDTs were observed in muscles of yellow catfish. The mean concentrations of
OCPs were 4.6 ng/L for water, 95 ng/g dry weight (dw) for aquatic plants, and 14 ng/g dw for sediments. Among the isomers
and metabolites, α-HCH and p,p′-1,1-di(p-chlorophenyl)-2,2-dichloroethylene (p,p′-DDE) were the predominant congeners in biota samples. Correlations between log lipid-normalized concentrations of HCHs and
DDTs and trophic levels (TLs) based on analysis of stable isotopes of nitrogen confirmed that persistent organic pollutants
were magnified in the Baiyangdian Lake food web. Significant positive relationships were found for α-HCH and p,p′-DDT and their trophic magnification factors, which were 1.6 and 1.7, respectively. These results provide evidence of biomagnification
of persistent organic pollutants (POPs) in freshwater food webs. 相似文献
14.
Occurrence and Ordination of Dichlorodiphenyltrichloroethane and Hexachlorocyclohexane in Agricultural Soils from Guangzhou,China 总被引:2,自引:0,他引:2
On a global scale tropical regions in developing countries are thought to be significant source areas of organochlorine pesticides
(OCPs), owing to a long history of widespread use and only a recent production ban or restriction on the application of these
pesticides. In the present study, 32 soil samples were collected in 2004 from agriculture lands around the urban area of Guangzhou,
in southern China, and analyzed for residues of OCPs including p,p’-DDT, p,p’-DDE, p,p’-DDD, and α-, β-, γ-, and δ-HCH. The dry weight concentrations of ΣHCH (ΣHCH = α-HCH + β-HCH + γ-HCH + δ-HCH) ranged from
0.2 to 103.9 ng/g, with a median of 4.4 ng/g. Residues of ΣDDT (ΣDDT = p,p’-DDT + p,p’-DDE + p,p’-DDD) ranged from 7.6 to 662.9 ng/g, with a median of 67.3 ng/g. The predominance of β-HCH among HCHs in most soil samples
suggested that they were from historical contamination rather than recent input. The mean HCH α/γ-ratio of 2.72 was lower
than that of technical HCHs, possibly due to more loss of α-HCH via evaporation from soil with time, conversion of γ-HCH to
α-HCH or recent application of lindane in the region. The mean ratio of (DDE + DDD)/ΣDDT was 0.54, indicating that quite a
portion of DDT in soils was degraded since its official ban in 1983. Higher DDT concentrations with lower (DDE + DDD)/ΣDDT
ratios at a few sites suggested possible local DDT sources via the application of Dicofol. A positive but weak correlation
(r = 0.449, p < 0.01) between DDT residues and TOC contents implied that soil organic matter might enhance adsorption of DDT in soils in
the tropical regions. Hierarchical cluster analysis and principal component analysis were also performed to study the distribution
and compositional patterns of OCPs as well as their sources and environemtal fates within the study area. 相似文献
15.
Residues of organochlorine pesticides (OCPs) in upper reach of the Huaihe River, East China 总被引:11,自引:0,他引:11
Residues of HCHs and DDTs in surface water and suspended particulate matter (SPM) from upper reach of the Huaihe River, East China, were investigated. Levels of total HCHs (∑HCH) and total DDTs (∑DDT) in water detected by GC-ECD ranged from 0.85 to 12.77 ng L−1 and from 3.54 to 33.59 ng L−1, respectively. According to European and America water quality guidelines, HCHs were within safe levels while DDT would pose adverse biological effects. Distribution of OCPs in water indicated that input of tributaries was important factor for the Huaihe River. For OCPs in SPM, concentrations varied from 1.01 to 25.22 ng g−1 for ∑HCH and not detected to 4.74 ng g−1 for ∑DDT. Compared with sediment quality guidelines, HCHs and DDTs might have an ecological risk. The main reason for OCPs residues in the Huaihe River was usage of lindane and technical DDT. Furthermore, composition of DDTs reflected fresh inputs of dicofol mixture in some sites. 相似文献
16.
The green mussel, Perna viridis, was used to measure bioaccumulated levels of organochlorine pesticides in the marine environment of Cuba. Samples were collected in the Cienfuegos Bay between January and December 2010. The organochlorine pesticides (i.e. DDT, Dieldrin, Chlordane, Endosulfan, HCB, Aldrin, Heptachlor and Lindane) were quantified by gas chromatography. The sum of all organochlorine pesticides in P. viridis was 6.31 ng g−1. The concentration ranged from 3.53 to 4.42 ng g−1 dry weight (dw) for DDTs (i.e. sum of pp’ DDT, pp’ DDD, op’ DDE and pp’ DDE); 1.7–1.9 ng g−1 dw for Dieldrin; 0.17–0.20 ng g−1 dw for Chlordanes; 0.14–0.16 ng g−1 dw for Endosulfan; 0.11–0.17 ng g−1 dw for HCB; 0.07–0.11 ng g−1 dw for Aldrin; 0.046–0.054 ng g−1 dw for Heptachlor and 0.035–0.039 ng g−1 dw for Lindane. These levels can be considered as low when compared to reported values from similar studies conducted elsewhere in the world. The concentrations of all organochlorines residues detected in this study fell below the EU Maximum Residue Limits. 相似文献
17.
Organochlorine Pesticides in Consumer Fish and Mollusks of Liaoning Province, China: Distribution and Human Exposure Implications 总被引:4,自引:0,他引:4
Zheng Liu Hongmei Zhang Minhui Tao Shaobin Yang Liwei Wang Ying Liu Dandan Ma Zhiming He 《Archives of environmental contamination and toxicology》2010,59(3):444-453
Fish and mollusk samples were collected from markets located in 12 cities in Liaoning province, China, during August and September
2007, and 22 organochlorine pesticides (OCPs) were detected. DDT, HCH, endosulfan, chlordane, and HCB were the dominating
OCPs, with mean concentrations and ranges of, respectively, 15.41 and 0.57 to 177.56 ng/g, 0.84 and below detection limit
(BDL) to 22.99 ng/g, 1.31 and BDL to 13.1 ng/g, 1.05 and BDL to 15.68 ng/g, and 0.63 and BDL to 9.21 ng/g in all fish and
mollusk samples. The concentrations of other OCPs generally were low and were detectable in a minority of samples, reflecting
the low levels of these OCPs in the study region. In general, OCP concentrations were obviously higher in fish than in mollusks,
and higher in freshwater fish than in marine fish, which indicated, first, that freshwater fish are more easily influenced
than seawater fish and mollusks by OCP residues in agricultural areas and, second, that there are different biota accumulation
factors for OCPs between fish and mollusk. To learn the consumption of fish and mollusk, 256 questionnaires were sent to families
in 12 cities of Liaoning province. Using the contamination data, average estimated daily intakes of OCPs via fish and mollusk
consumption were calculated, which were used for exposure assessment. The public health risks caused by exposure to OCPs in
the course of fish and mollusk consumption were compared to noncancer benchmarks and cancer benchmarks. 相似文献
18.
Wepener V Smit N Covaci A Dyke S Bervoets L 《Bulletin of environmental contamination and toxicology》2012,88(2):277-282
The study determined current exposure of tigerfish in Lake Pongolaqpoort to organohalogens. Levels of DDT, PCB, HCB, HCH,
PBDE and CHLs were measured in tigerfish muscle on a seasonal basis. Historical use of DDT was reflected in the bioaccumulation
patterns (5,400–6,000 ng/g lipid) as well as current use of HCBs (7.7–15.7 ng/g lipid) in the agricultural areas. External
factors, i.e. increased flow did not play a role in organic pollutant exposure. Levels are a function of the lipid content
of the muscle tissue, i.e. 3.8% during low and 9% during high flow, implying that organohalogen exposure remains fairly constant
throughout the year. 相似文献
19.
Persistent Organochlorine Compounds in Human Milk Collected in Croatia Over Two Decades 总被引:1,自引:0,他引:1
B. Krauthacker A. Votava-Rai? S. Herceg Romani? D. Tje?i?-Drinkovi? Do. Tje?i?-Drinkovi? E. Reiner 《Archives of environmental contamination and toxicology》2009,57(3):616-622
The distribution and time trend of organochlorine pesticide (OCP), polychlorinated biphenyl (PCB), and polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran (PCDD/PCDF) concentrations in human milk samples from Croatia collected in 1981–2003
are presented. Between 1981/1982 and 1987/1989, the concentrations of HCB, β-HCH, DDE, and total PCBs decreased about 50%,
while for the last decade, the concentrations have been decreasing very slowly. In 2002/2003 the range of PCB congeners and
OCPs was from below the limit of determination to 332 ng g−1 milk fat. PCDD/PCDF concentrations in human milk samples collected in 1981–2000 ranged between 5.2 and 26.7 pg I-TEQ g−1 milk fat and showed a decreasing trend. 相似文献
20.
Jie Chi 《Bulletin of environmental contamination and toxicology》2009,82(4):510-515
Organochlorine pesticides (OCPs) concentrations in sediments and sediment trap fluxes of particulate organic carbon and OCPs
were measured from October 2006 to May 2008 in the urban reach of Haihe River, Tianjin, China, in order to investigate vertical
fluxes and accumulation of OCPs in sediments. The concentrations of OCPs in sediments (dry weight basis) were in the range
of 2.08–10.07 ng/g (mean 4.70 ng/g) for HCHs (α-, β-, γ-, δ-HCH), 5.82–43.39 ng/g (mean 17.43 ng/g) for DDTs (p,p′-DDE, p,p′-DDD,
o,p′-DDT, p,p′-DDT). Compared with data reported in Haihe River 2003, the levels of OCPs showed a significant decrease between
2003 and 2008. This is mainly attributed to significant decrease of production and usage of HCHs and DDTs and biodegradation
of HCHs and DDTs in sediment. Concentrations of HCHs and DDTs in sediments were well correlated with sediment organic carbon
contents. Concentrations of OCPs in settling particles (dry weight basis) ranged from 21.2 to 138.4 ng/g (mean 52.6 ng/g)
for HCHs, 30.0–245.7 ng/g (mean 87.1 ng/g) for DDTs, which were 2.2–48.2-fold higher than those associated with sediments.
β-HCH was the dominant HCH isomer in both sediments and settling particles. Among DDTs, p,p′-DDE was found to be dominant
in sediments, while p,p′-DDT was the predominant form in settling particles. This suggests that further biodegradation of
OCPs occurred during the course of sedimentation and burial. The annual sediment trap flux of OCPs in Haihe River in the urban
area of Tianjin was 177–211 μg/m2 yr for HCHs and 213–341 μg/m2 yr for DDTs, respectively. 相似文献