Concentrations and Accumulation Features of Organochlorine Pesticides in the Baiyangdian Lake Freshwater Food Web of North China

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.     

Organochlorine Pesticides in Muscle of Wild Seabass and Chinese Prawn from the Bohai Sea and Yellow Sea,China

Muscle samples from wild seabass and Chinese prawn collected from the Bohai Sea and the Yellow Sea, China were analyzed for 22 organochlorine pesticides. DDTs were the predominant contaminants in all samples. The concentration of DDTs in seabass was 247 μg kg⁻¹ wet wt (from 4.30 to 2,089 μg kg⁻¹ wet wt). Significantly, concentration of DDTs in seabass was much higher than that in prawn (6.51 μg kg⁻¹ wet wt). Very high concentrations of DDTs and high DDT/DDTs ratio were found in seabass samples from some locations, which imply there might be new inputs of DDT into the marine environment.     

Profiles of Organochlorine Pesticides in Earthworms from Urban Leisure Areas of Beijing, China

In this study, organochlorine pesticides (HCHs and DDTs) in earthworm and soil contacted closely with it were determined for the purpose of the risk assessment of chemicals in the urban leisure environment. The level of total hexachlorocyclohexanes and (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) in earthworms was 0.6500–44.78 ng g⁻¹ and 18.97–1.112 × 104 ng g⁻¹, respectively. Absolutely high levels of DDT and its metabolites in earthworm and correlative soils samples, and the bioaccumulation factor (BAF) of DDTs probably presents certain risk to the higher trophic organisms through its food chain, especially birds.     

Persistent Organic Pollutants (PCBs and DDTs) in European Conger Eel, <Emphasis Type="Italic">Conger conger</Emphasis> L., from the Ionian Sea (Mediterranean Sea)

The present study provides novel data regarding levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (DDTs) in muscle tissue of European conger eel (Conger conger) from Ionian Sea (Mediterranean Sea). The mean concentration of PCBs (891 ng g⁻¹ lipid weight) was higher than those of DDTs (543 ng g⁻¹ lipid weight). PCB pattern was dominated by higher chlorinated congeners (hexa-CBs: 69.3 %, penta-CBs: 17.2 %, hepta-CBs: 13.3 %). Regarding DDT pattern, p,p′-DDE was prevalent in all samples (85.5 %), suggesting no recent DDT input. The total 2,3,7,8-TCDD toxic equivalent (TEQs) of coplanar PCBs, including mono-and non-ortho congeners was 0.41 pg g⁻¹ wet weight (29.92 pg g⁻¹ lipid weight). The PCB and DDT levels, as well as TEQ concentrations were lower than most of the corresponding published data for fish from Mediterranean and non-Mediterranean regions, probably reflecting a moderately contaminated area.     

Distribution and Sources of Organochlorine Pesticides in Taihu Lake, China

Thirty surface sediments, corresponding overlying water and porewater samples were collected for analysis of organochlorine pesticides (OCPs) from Taihu Lake, China in May 2010. Altogether six OCPs, i.e. hexachlorobenzene (HCB), β-hexachlorohexane (β-HCH), p,p′-DDE, p,p′-DDD, p,p′-DDT, and o,p′-DDT were detected, and the total OCPs varied from 7.84 to 32.23 ng g^?1 in sediments, from 136.97 to 2,185.14 ng L^?1 in porewater and from 24.27 to 154.07 ng L^?1 in overlying water, respectively. The highest levels of contamination in sediment was observed in southeast of the lake, while in water and porewater samples highest levels were found in Zhushan Bay, the seriously polluted area in the north part of Taihu Lake. The partition coefficient of measured OCPs between sediment-overlying water was five and six fold higher than that between sediment-porewater, indicating the different distribution patterns of OCPs among sediment, overlying water and porewater matrices. The ratios of DDT/(DDD + DDE) ranged from 0.57 to 2.28 in sediments, 0.93–13.02 in porewater and 0.84–15.98 in overlying water, respectively, suggesting the potential new source of DDTs into the lake. The ratios of o,p′-DDT/p,p′-DDT in the three matrices were centered around 0.2–0.3, indicating the o,p′-DDT in the lake was originated from historical usage of technical DDTs.     

Ecological Risk Assessment of HCH and DDT Residues in a Sediment Core from the Küçükçekmece Lagoon,Turkey

The residues of organochlorine pesticides (HCHs and DDTs) in a dated (¹³⁷Cs and ²¹⁰Pb) sediment core from the Küçükçekmece Lagoon, an urban lake at the southern entrance of the future Canal Istanbul Project, an artificial watercourse, were analyzed with the gas chromatograph equipped with electron capture detector (GC ⁶³Ni-ECD). Concentrations of ∑HCH and ∑DDT along the core varied between 0.4 and 469.4 (average 51.4) ng g^?1 dw, and between 0.5 and 72.0 (average 7.4) ng g^?1 dw, respectively. α-HCH was the predominant isomer (98%) and followed by γ-isomer (2%). The highest concentrations of technical HCH were found in the sediments dated 1963–1972, whilst the DDT concentrations had their maximum around 1945. The highest concentrations of γ-HCH and p,p′-DDT exceeded probable-effect level values which can lead to frequently cause adverse effects on aquatic biota.     

Status of Organochlorine Contaminants in the Different Environmental Compartments of Pakistan: A Review on Occurrence and Levels

This review evaluates and summarizes the results of the studies of organochlorines-contaminated water, sediment/soil and biota in Pakistan. Pattern of occurrence of each contaminant class from different study sites is followed as DDTs > Cyclodiens > HCHs > PCBs. The studies conducted in the surrounding areas of the demolished DDT manufacturing units and obsolete pesticides stores of country showed extremely highest values of ∑DDTs, which differ significantly (p < 0.05) than those reported from the agricultural areas and fresh water bodies of the country. HCHs, heptachlor, dieldrin, and HCB were also reported in many studies, but the concentrations are comparable among all the locations in the country. The authors suggested surface run-off, dumping of waste from industries and contamination from obsolete pesticides and demolished OCPs manufacturing units as the major sources in Pakistan. Information on PCBs is scares and studies on assessment of PCBs occurrence, and spatial trends in various environmental matrices needs special attention to produce the scientific publication. The results draw attention that POPs contamination must be considered as a priority environmental concern due to their use in agricultural and industrial sector.     

Organochlorine Contaminants in Water, Sediment and Fish of Lake Burullus, Egyptian Mediterranean Sea

Lake Burullus is one of the Delta lakes, connected with the Mediterranean Sea through El Boughaz opening. Concentrations of organochlorine contaminants were measured in water, sediments and biota of the lake because of concerns about their effects on its productivity. The concentrations of chlorinated hydrocarbons decreased in the order of PCBs > DDTs > TC > HCHs for all water samples collected from Lake Burullus during 2006. Higher concentrations were recorded during summer season, this clearly affected by higher agricultural and sewage activities. The concentrations of DDTs in water were ranged from 0.07 to 221.9 ng L(-1); 46.3-656.5 ng L(-1); 94.3-882.6 ng L(-1) and 24.8-233 ng L(-1) during winter, spring, summer and autumn, respectively. Among DDTs metabolites p,p-DDE was the most dominant with a maximum of 520.13 ng L(-1) recorded at station 10 (El Boughaz opening). In sediment samples, PCBs concentrations were ranged from 4.6 to 213.9 ng g(-1) with an average 47.2 ng g(-1); dry weight. Total pesticides were higher than PCBs for mostly all sediment samples of Lake Burullus. Concentrations of DDTs in fish tissues were ranged from 2.76 to 24.23 ng g(-1) and from 14.16 to 45.13 ng g(-1); wet weight for Oresochromus niloticus and Clarries sp., respectively.     

Mercury concentrations are low in commercial fish species of Lake Ziway, Ethiopia, but stable isotope data indicated biomagnification

Stable isotope ratios of nitrogen (δ¹⁵N) and carbon (δ¹³C), complemented by stomach content data, were used to assess the food web structure and trophic transfer of mercury (Hg) in four commercial fish species of Lake Ziway, Ethiopia: Nile tilapia (Oreochromis niloticus), catfish (Clarias gariepinus), Tilapia zillii, and golden carp (Carassius auratus). Total mercury (THg in mg kg⁻¹, ww) concentrations were low, with mean values of 0.033, 0.034, 0.025, and 0.011, in C. gariepinus, T. zillii, C. auratus, and O. niloticus, respectively. The relationships between mercury concentrations against total length (TL) and total weight (TW) were positive and significant in T. zillii, C. auratus, and C. gariepinus (P<0.01), but not in O. niloticus, which even showed a decreasing tendency with increase in TL and TW. Regression of log THg vs. δ¹⁵N among all fish species showed a significant correlation, indicating that mercury is biomagnifying along the food web of Lake Ziway. Isotope ratios indicated that C. gariepinus occupied the highest trophic level of the food web of Lake Ziway; but contained similar THg concentrations as T. zillii, which is located at a lower trophic level, probably due to a faster growth rate of C. gariepinus, and thus an example of biodilution.     

Organochlorine Pesticides in Green Mussel, <Emphasis Type="Italic">Perna viridis,</Emphasis> from the Cienfuegos Bay,Cuba

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.     

HCH and DDT in Sediments from Marine and Adjacent Riverine Areas of North Bohai Sea, China

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.     

Distribution of HCHs and DDTs in Soils from Beijing City, China

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.     

HCH and DDT Residues in Bivalves <Emphasis Type="Italic">Anodonta woodiana</Emphasis> from the Taihu Lake,China

The present article attempts to use freshwater bivalves Anodonta woodiana for monitoring the pollution of hexachlorocyclohexane isomers (α-, β-, γ-, δ-HCH), dichlorodiphenyltrichloroethanes (o, p′, p, p′-DDT) and metabolites (p, p′-DDE, p, p′-DDD) in the Taihu Lake, China. A total of 36 bivalves were sampled from 4 sites of Huzhou city, Dapu of Yixing city, Xueyan of Changzhou city, and Wulihu of Wuxi city around the lake in August–October 2004. The organochlorines were detected in all bivalves, and the mean concentration of ΣDDTs (7.07 ng/g wet weight) was significantly higher than that of ΣHCHs (2.37 ng/g wet weight). Overall, ΣHCHs are at the highest concentrations in the bivalves from the Dapu and Huzhou site, whereas ΣDDTs are at highest concentrations in the bivalves from the Wulihu site. Compositions of ΣHCHs were predominated by α- and γ-HCH isomers in the bivalves from all four study sites. Among these sampling sites, p, p′-DDT exhibited the highest percentage in the bivalves from Huzhou site. Furthermore, significant regional variations in compositions of both ΣDDTs and ΣHCHs had been identified. The residue levels of ΣDDTs and ΣHCHs in the bivalves of the present study were much lower than the corresponding residue limits for aquatic products of Ministry of Agriculture of China, FDA, and FAO/WHO. These findings suggest that Anodonta woodiana could serve as a unique bioindicator to monitor the HCH and DDT pollutions in the freshwater environment.     

Contamination Profile of DDTs in the Shark <Emphasis Type="Italic">Somniosus microcephalus</Emphasis> from Greenland Seawaters

DDT isomers were detected in all the liver and muscle samples of Greenland sharks Somniosus microcephalus (n?=?15) caught in Greenland seawaters. The mean concentrations of ΣDDTs (sum of o,p’ and p,p’ DDT, DDD, and DDE isomers) were 1094?±?818 ng/g lipid weight (lw) in the muscle and 761?±?416 ng/g lw in the liver. The p,p’-DDE accounted for 48%?±?41% and 53%?±?54% of the total DDT residue in the white muscle and liver, respectively. The lipid content was 48%?±?10% in the muscle and 43%?±?17% in the liver. Female sharks showed the highest concentrations of ΣDDTs. The youngest shark showed higher concentrations of ΣDDTs in the liver than the older sharks. To our knowledge, this is one of the few investigations on DDT levels in S. microcephalus where concentrations were correlated to lipid content and sex/size.     

Organochlorine Pesticides in the Soil in Linfen,China

Ten soil samples collected in Linfen were analyzed for 21 organochlorine pesticides. The concentration of total organochlorine pesticides ranged from 4.3 to 23.2 ng g⁻¹ in soil from urban areas and from 26.3 to 247.4 ng g⁻¹ in soil from industrial plants. The highest levels of contamination were observed in northwest and central Linfen, reflecting the distribution of industrial plants. The HCH and DDT profiles revealed that the sources were associated mainly with lindane and technical DDT, respectively, while HCHs in the soil of industrial plants might originate from a new source.     

Investigating the Spatial Trends in the Level of Organic Contaminants in the Ethiopian Rift Valley Lakes Using Semipermeable Membrane Devices

Organic pollutants in the Ethiopian Rift Valley Lakes are the major factors that contribute to severe environmental problem. SPMDs were deployed for the analysis of selected organic pollutants for 1?month at 2 sites in Lakes Hawassa, Ziway and Koka, Ethiopia. From SPMDs placed in the three lakes, the predominant OCPs were DDT which comprise 67% and followed by endosulfan 23% of the total organochlorine pesticides (OCPs) retrieved. The highest level of OCPs, in general, was found in the SPMDs deployed in Lake Ziway with the mean concentration of 308.5 ng/SPMD. However, the concentrations of polychlorinated biphenyls (PCBs) were the highest in the SPMDs deployed in Lake Hawassa with mean concentration of 50.2 ng/SPMD. Spatial variation on the accumulation of OCPs and PCBs among the lakes depends on the shoreline activities, distance of the lakes from point and non-point sources, and the biofouling factors.     

Levels and Sources of Organochlorine Pesticides in Surface Sediment from Anhui Reach of Huaihe River,China

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.     

Toxicity of Chloride Under Winter Low-Flow Conditions in an Urban Watershed in Central Missouri,USA

The objective of this study was to determine the levels of organochlorine pesticides HCB, α-β-γ-HCH, pp′DDE, op′DDT and pp′DDT in adipose tissue of females living in Puebla, Mexico. Organochlorine pesticides were analyzed in 75 abdominal adipose tissue samples taken during 2010 by autopsy at the Forensic Services of Puebla. The results were expressed as mg/kg on fat basis. In analyzed samples the following pesticides were detected: p,p’-DDE in 100% of samples at mean 1.464 mg/kg; p,p’-DDT in 96.0.% of samples at mean 0.105 mg/kg; op′DDT in 89.3% of monitored samples at mean 0.025 mg/kg and β-HCH in 94.7% of the samples at mean 0.108 mg/kg. To show if organochlorine pesticide levels in monitored female’s adipose tissues are age dependant, the group was divided in three ages ranges (13–26, 26–57 and 57–96 years). The mean and median levels of all organochlorine pesticides increase significantly (p < 0.05) from the first to second and from the first to third group. At the same time, the increase of mean and medians levels from the second to third group were not statistically significant (p > 0.05). The present results compared to previous ones from 2008 indicates an increase in the concentrations during the 2010 study, but only the differences for pp’DDE and op’DDT were statistically significant. The 2010 group of females was older compared to the 2008 group. The presence of organochlorine pesticide residues is still observed, indicating uniform and permanent exposure to the pesticides by Puebla inhabitants.     

Sixty-Year Sedimentary Record of DDTs, HCHs, CHLs and Endosulfan from Emerging Development Gulfs: A Case Study in the Beibu Gulf, South China Sea

The temporal distribution of organochlorine pesticides (OCPs) was examined in the ²¹⁰Pb dated sediment core from the Beibu Gulf, South China Sea. The total OCPs concentrations were in the range of 0.93–26.6 ng g^?1 dry weight. Dichlorodiphenyltrichloroethanes (DDTs) (0.17–24.8 ng g^?1), Hexachlorocyclohexanes (HCHs) (0.04–0.51 ng g^?1), Chlordane related compounds (CHLs) (0.22–1.72 ng g^?1) and endosulfan (n.d.–0.91 ng g^?1) were the predominant compounds. Similar to most Chinese coastal areas, the levels of DDTs in the Beibu Gulf became elevated since the early 1990s, especially since 2000 despite the ban in 1983 in China. This suggests that the concentrations of DDTs were controlled by several processes, such as land reclamation and soil runoff. The isomer ratios of (p,p′-DDE + p,p′-DDD)/p,p′-DDT, p,p′-DDT/DDTs along with construction land expansion indicated that economic activities, land reclamation, soil runoff and the use of DDT-containing antifouling paints might be responsible for the input of DDT. The ratios of α-HCH/γ-HCH (and γ-HCH/HCHs) and trans-chlordane/cis-chlordane (TC/CC) indicated fresh inputs of lindane and chlordane, respectively. In addition, CC was found to be degraded faster than TC under anaerobic conditions in sediments from the Beibu Gulf.     

Persistent DDE in the Mesopotamian Wetlands of Southern Iraq

Screening of potential pollutants in surface sediments revealed that almost all persistent organochlorine pesticides were not detected in the newly flooded Mesopotamian wetlands of southern Iraq. This observation suggests that there has been minimal input of organochlorine pesticides recently except for p,p′-DDE which was the only pesticide residue detected (0.29–2.33 μg/kg). It was found in all samples indicating its ability to persist under severe drying of previously exposed surface sediments, high temperature, and intensive solar radiation. p,p′-DDE appears to have a negative relationship with wetland biota, such as zooplankton.