太湖流域沉积物中有机氯农药空间分布特征及风险评价

为了解太湖流域表层沉积物中有机氯农药的空间分布和污染特征,采集全流域111个表层沉积物样品,用GC-μECD分析了20种有机氯农药的含量,并基于沉积物质量基准法对沉积物污染风险进行评价。结果表明:太湖流域沉积物中20种有机氯农药(OCPs)的总含量介于16. 3～96. 9 ng/g dw之间,平均值为35. 0ng/g dw,其中HCHs和DDTs是主要的检出成分,平均含量分别为12. 1、7. 6 ng/g dw,两者含量之和占总OCPs的25. 5%～85. 5%。特征化合物指数法分析结果表明,HCHs主要来源于林丹,而且该区域仍然有新的DDT输入,并且大部分p,p’-DDT通过好氧生物降解为p,p’-DDE。沉积物质量基准法评价结果显示,γ-HCH、DDTs潜在生物毒性较大。     

南京某地农业土壤中有机污染分布状况研究

对某大型矿业企业周边农业土壤中两类POPs物质——15种多环芳烃和有机氯农药（DDTs和HCHs）的残留量进行了调查。结果表明,PAHs检出率为100%,总残留量范围为312.2~27 580.9 μg·kg-1,且以四环以上多环芳烃组分为主。不同样区土壤PAHs残留量受常年风向影响明显。农业土壤中有机氯农药六六六和滴滴涕均有检出,但残留水平不高,分别为3.60 μg·kg-1(0.81~9.43 μg·kg-1)和11.13 μg·kg-1(3.31~43.81 μg·kg-1)。土壤有机氯农药的残留以p,p′ DDE和p,p′ DDT为主。土壤中HCHs的各异构体组分含量特征为α>β>γ>δ。部分采样点土壤仍可能有新的有机氯污染物来源。     

城市内湖表层沉积物中有机氯农药残留特征及风险评价

中国曾大量生产和使用有机氯农药(OCPs),目前虽已被禁止生产和农业中使用,但含三氯杀螨醇的林丹和滴滴涕(DDTs)仍在非法生产和使用。为了解农业大省江西省城市内湖OCPs的残留情况,以鄱阳湖生态经济区象湖为研究对象,用GC/ECD 分析象湖表层沉积物中8 种OCPs的残留水平,采用ArcGIS空间分析、主成分分析法探讨OCPs 的残留特征、来源及其可能的风险。结果表明,8 种OCPs 在象湖表层沉积物中均有不同程度检出,六六六( ∑ HCHs) 含量为nd~61.89 ng/g, ∑ DDTs含量为nd~81.47 ng/g。含量较高的组分为o,p'-DDT、β-HCH和δ-HCH。象湖表层沉积物中OCPs残留空间分布不均,其中象湖南边湿地花卉公园沉积物中OCPs含量相对较高。同中国其他城市内湖/内河相比,象湖表层沉积物中HCHs和DDTs残留水平偏高,这可能与象湖区域曾经作为南昌市农业发展区有关。来源解析结果表明象湖HCHs和DDTs主要来源于农药的历史使用,但近年来很可能有林丹和三氯杀螨醇的输入。风险评价结果显示目前象湖表层沉积物中DDTs类污染物对人体健康风险总体处于较低水平,但湿地花卉公园周边环境生态风险较高,对周围环境的生物毒性较大。研究结果可为城市内湖的污染控制及风险管理提供科学依据。     

三峡库区水体有机氯农药污染特征

在长江三峡库区采集了111件水体样品,并用气相色谱(GC ECD)内标法分析其有机氯农药(OCPs)的含量,探讨了研究区水体中OCPs的残留水平、分布及来源。结果表明：水体中OCPs指标,检出率为100%。HCH四种同分异构体含量范围分别为α HCH 010~608 ng/L,β HCH 048~1020 ng/L,γ HCH 009~843 ng/L,δ HCH 007~1053 ng/L;DDT类化合物检出率普遍较低,含量范围是：p,p' DDE 001~1914 ng/L,p,p' DDD 0.04~213 ng/L,p,p' DDT 007~164 ng/L。两类农药中HCHs在多数采样点上都能被检测到,在总体含量上干流断面HCHs普遍高于DDTs。长江干流重点位置与库区断面含量相比,HCHs高于断面,DDTs低于断面。HCHs在水库水体干流中的分布呈跳跃式波动,且每次含量波动幅度都要比前一次高。库区干流重点位置水体以β HCH为主,但δ HCH普遍存在。库区重点位置水体未能检测到DDT,表明其对库区水体DDTs的贡献较小。通过比值分析得出大气输入是库区水体DDT类物质的主要来源     

长江宜昌江段几种鱼类体中六六六、滴滴涕的残留水平

利用毛细管电子捕获气相色谱法测定了长江宜昌江段采集的几种鱼样组织内六六六(HCHs)、滴滴涕(DDTs)的残留量.结果表明,在鱼体肌肉、脂肪和肝脏这三种组织中,HCHs、DDTs主要蓄积在鱼体肝脏,其次是脂肪组织,肌肉组织中残留量较低.鱼体肌肉组织中HCHs残留量低于0.5 ng/g,肝脏中的HCHs是其脂肪组织的2倍,最高为27.6 ng/g,主要为悛睭CH所贡献,猹睭CH和洫睭CH未检出.DDTs在鱼体肌肉、脂肪和肝脏组织中的残留量分别为0.4～14.8、12.5～147、33.4～286 ng/g.鱼体组织中DDTs主要以p,p′-DDE的形式存在,p,p′-DDE残留量占∑DDTs的70%左右.与国内外不同水域的鱼体中HCHs、DDTs残留量相比较,长江宜昌江段鱼体肌肉中HCHs和DDTs残留水平较低.     

城市内湖表层沉积物中有机氯农药残留特征及风险评价——以鄱阳湖生态经济区南昌市象湖为例

中国曾大量生产和使用有机氯农药(OCPs),目前虽已被禁止生产和农业中使用,但含三氯杀螨醇的林丹和滴滴涕(DDTs)仍在非法生产和使用。为了解农业大省江西省城市内湖OCPs的残留情况,以鄱阳湖生态经济区象湖为研究对象,用GC/ECD分析象湖表层沉积物中8种OCPs的残留水平,采用ArcGIS空间分析、主成分分析法探讨OCPs的残留特征、来源及其可能的风险。结果表明,8种OCPs在象湖表层沉积物中均有不同程度检出,六六六(∑HCHs)含量为nd~61.89ng/g,∑DDTs含量为nd~81.47ng/g。含量较高的组分为o,p’-DDT、β-HCH和δ-HCH。象湖表层沉积物中OCPs残留空间分布不均,其中象湖南边湿地花卉公园沉积物中OCPs含量相对较高。同中国其他城市内湖/内河相比,象湖表层沉积物中HCHs和DDTs残留水平偏高,这可能与象湖区域曾经作为南昌市农业发展区有关。来源解析结果表明象湖HCHs和DDTs主要来源于农药的历史使用,但近年来很可能有林丹和三氯杀螨醇的输入。风险评价结果显示目前象湖表层沉积物中DDTs类污染物对人体健康风险总体处于较低水平,但湿地花卉公园周边环境生态风险较高,对周围环境的生物毒性较大。研究结果可为城市内湖的污染控制及风险管理提供科学依据。     

太湖流域铜锈环棱螺体内重金属富集量及膳食风险评价

对太湖流域6个水系铜锈环棱螺腹足肌肉团Cu、Zn、Pb、Cr、Cd、As、Hg富集量进行分析,运用单因子污染指数法评价其受污染程度,并分别采用平均每周/每月摄入量法和目标危害系数法(THQ)对其膳食风险进行评估,旨在为居民铜锈环棱螺消费安全提供参考。结果表明,洮滆水系的Cu、Zn、Pb、Cr元素富集量平均值最高,分别为112.108、248.625、4.422、7.791 mg/kg,苕溪水系Cd、As、Hg元素富集量平均值最高,分别为0.290、2.943、0.059 mg/kg。THQ评价结果显示各水系铜锈环棱螺除了As外无单一重金属潜在健康风险,但多种重金属复合暴露的健康风险(TTHQ)结果显示各水系铜锈环棱螺重金属TTHQ值均大于1,As的贡献率均超过80%,表明居民长期食用环棱螺具有重金属复合暴露健康风险及As单一重金属潜在健康风险,重金属复合暴露风险来源于As元素的污染。五个水系潜在重金属复合暴露风险排序为：洮滆水系>苕溪水系>沿江水系>黄浦江水系>杭州湾-长江口水系。     

升温对铜锈环棱螺形态及春季个体增补影响的模拟实验研究

气候变暖已成为近几十年研究的热点,但是有关温度升高对螺类形态变化的研究还为数不多。利用中型室外模拟控制系统(Mesocosm)模拟百年之后长江中下游地区浅水湖泊水生态系统,实验设置对照组与升温组两个处理,以此探求水体温度升高对铜锈环棱螺(Bellamya aeruginosa)形态的影响。应用几何形态测量学得到铜锈环棱螺壳高、壳宽、轮廓面积与周长4个形态参数,并分别与质量进行回归分析。通过协方差分析比较两种处理回归方程的差异,发现螺类周长随温度升高发生显著变化,同时升温增加了螺类春季个体增补数量。升温对于螺类形态变化影响体现在以下3方面:升温显著增加了铜锈环棱螺的密度,加剧了种群个体间竞争,促使性成熟个体趋于小型化;升温改变铜锈环棱螺食物质量,通过影响螺类生长过程对螺类形态变化产生作用;升温改变了水体p H值,进而影响螺类外壳的钙化率和水体中钙可利用程度,对螺类外壳形成产生直接的影响,最终导致螺类形态变化。     

上海淀山湖及黄浦江上游鱼类物种多样性及群落结构分析

为了解淀山湖及黄浦江上游的鱼类物种多样性组成及群落结构状况,于2020年6月(夏季)和10月(秋季)在10个采样断面对鱼类样本作了定量和定性采集,并对其多样性及群落结构作了分析。2次调查共采集鱼类11 408尾、49种,隶属于9目14科37属。夏季和秋季,淀山湖5个断面合计有鱼类29种和30种,黄浦江上游5个断面有37种和29种,刀鲚(Coilia nasus)、鲫(Carassius auratus)和大鳍鱊(Acheilognathus macropterus)为主要优势种。两个水体秋季的Shannon-Wiener多样性指数(H^’)、Pielou均匀度指数(J^’)、Simpson优势度指数(C)和Margale丰富度指数(D)指数均值都高于夏季的均值。相似性分析显示淀山湖各断面之间的鱼类群落相似性高于黄浦江上游各断面之间。ABC曲线表明,淀山湖及黄浦江上游鱼类群落结构总体上并不稳定,特别是淀山湖区域。Cluster聚类和非参数多维标度排序分析可明显将鱼类群落分为黄浦江群组Ⅰ、淀峰群组Ⅱ和淀山湖群组Ⅲ,似鳊(Pseudobrama sim...     

淀山湖浮游植物叶绿素a粒径组成及其与水质因子相关性

于2005年6月至2006年5月对淀山湖小型(20～200μm)、微型(2～20μm)和微微型(<2μm)浮游植物叶绿素a和水质因子进行逐月调查研究。结果表明:小型和微型浮游植物是淀山湖水体年均叶绿素a的主要贡献者,二者贡献率之和为74.79%。淀山湖叶绿素a粒径组成百分比的季节变动与水体浮游植物群落结构季节演替密切相关:小型浮游植物叶绿素a浓度所占百分比春季最高,而微型、微微型的则分别在秋、冬季最高。相关性分析显示,小型、微型浮游植物叶绿素a浓度百分比与NH3-N含量分别呈显著正、负相关,微微型浮游植物叶绿素a百分比与BOD5呈极显著负相关。对应滤食性鱼类等水生动物的食性粒级,探讨了运用非经典生物操纵技术防治淀山湖富营养化的可行性。     

Organochlorine levels in edible fish from the Marmara Sea, Turkey

Samples of 12 edible fish species from the Marmara Sea were analyzed for organochlorines (PCBs, DDTs, HCB, HCHs, toxaphene, etc.). The results showed that the total concentrations ranged from 329.41 ng/g fat to 1453.87 ng/g fat. DDT group components made up almost half or more of organochlorine contamination. Levels in red mullet were compared with those from neighbor seas. The sum of DDTs as well as HCHs concentrations were markedly lower than in the Black Sea but higher in the Aegean Sea and Mediterranean. Thus, inflow from the Black Sea might be considered as a contamination source for DDT and HCH contamination. On the other hand, total PCB concentration (sum of congeners 28, 52, 101, 118, 138, 153 and 180) detected in this study was comparable or lower than those from the Aegean Sea and Mediterranean. Toxaphene was a minor contaminant. Measured values were below maximum residue levels for human consumption.     

Levels and trends of persistent organic pollutants in ringed seals (Phoca hispida) from Central West Greenland, with particular focus on polybrominated diphenyl ethers (PBDEs)

Polybrominated diphenyl ethers (PBDEs) and the organochlorine compounds polychlorinated biphenyls (PCBs), DDTs, HCB, chlordane-related pesticides, HCH and toxaphene were analysed in blubber of juvenile ringed seals from Central West Greenland collected between 1982 and 2006. The longest time series could be established for PBDEs, partly based on archived material, while PCBs and DDTs covered a study period from 1994-2006. All organochlorines showed decreasing trends, most pronounced for DDT and HCH with an annual change of 8%. BDE-47 had a significantly increasing trend of 5% annually. It was the only BDE congener consistently above the detection limit, with annual median concentrations between 0.78 ng/g lw to 3.54 ng/g lw, i.e. about 10 times lower than values from East Greenland observed in a similar time trend study on ringed seal blubber [Rigét F, Vorkamp K, Dietz R, Rastogi SC. Temporal trend studies on polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in ringed seals from East Greenland. J Environ Monit 2006; 8: 1000-5]. A clear East>West difference was also found for PCBs and DDTs, but not for chlordanes, toxaphene or HCHs. Sigma 10-PCB, Sigma DDT and Sigma Chlordanes had similar annual median concentrations, typically exceeding SigmaPBDE by two orders of magnitude. The concentrations of HCH and toxaphene were in an intermediate group, with highest annual median concentrations of 135 ng/g lw and 20 ng/g lw, respectively. For most compound groups, the circumpolar trend previously established under for example the Arctic Monitoring and Assessment Programme was confirmed, but apparently, more data are needed for chlordane-related compounds and toxaphene. Statistical analyses of the compound patterns in the ringed seal samples revealed significantly greater differences between seals from East and West than between different sampling years. Higher proportions of PCBs and DDTs and lower proportions of chlordanes and HCHs were found in seals from East Greenland than in those from West Greenland. Based on principal component analysis of individual congener and compounds, seals from East Greenland were found to contain higher proportions of the higher chlorinated CB congeners. Varying patterns between sampling locations may be caused by different exposure situations related to contaminant emissions and transport, but different feeding habits may also affect the contaminant composition.     

Organochlorine pesticide and polychlorinated biphenyl residues in feathers of birds from different trophic levels of South-West Iran

Persistent organochlorine pesticides (OCPs), such as dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), alpha, beta and gamma-hexachlorocyclohexane (HCH) isomers, together with polychlorinated biphenyl (PCB) congeners (IUPAC Nos. 28, 52, 101, 138, 153 and 180), were determined in tail feathers from 37 birds belonging to 18 species, all originating from the South-West of Iran (Khuzestan, coast of the Persian Gulf). This is the first report on organochlorine contaminants in feathers from museum collections and it is an indication of the concentrations of OCPs and PCBs in the past (1991-1996). Median concentrations of HCHs, DDTs, PCBs and HCB were 22, 14, 11 and 10 ng/g feather, respectively. Significant correlations (p<0.05) were calculated between OCPs (except HCB) and PCBs in the bird feathers. p,p'-DDE and gamma-HCH were the most abundant OCPs, while CB 180, CB 138 and CB 101 were the predominant PCB congeners in almost all species. Significant differences (p<0.05) in the mean concentrations of DDTs and PCBs were detected among species grouped according to their feeding habits. Levels of DDTs and PCBs were highest in the carnivorous species and lowest in the herbivorous species. Levels of OCPs and PCBs in feathers of bids in the 1990s were generally below the thresholds reported to affect reproduction.     

Evaluation of the concentration of HCH, DDT, HCB, PCB and PAH in the sediments along the lower stretch of Hugli estuary, West Bengal, northeast India

Detailed analyses of persistent organic pollutants (POPs) such as hexachlorocyclohexane (HCH) isomers (HCHs), dichlorodiphenyltrichloro ethane (DDT) and its metabolites (DDTs), hexachlorobenzene (HCB) and congeners of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in surface sediments from the coastal estuarine environment of West Bengal, northeast India allowed the evaluation of the contamination status, distribution and possible pollution sources. HCH, DDT, HCB, PCB and PAH were identified compounds in all the samples, whereas the concentrations of chlorinated pesticides (trans-eptachlorepoxide, dieldrin, endrin, metaoxychlor and mirex) were below the detection limits and were not of great concern. The pesticides did demonstrate markedly different distributions reflecting different agricultural and domestic usage in the region. The range of concentrations of HCH, HCB, DDT and PCBs in the sediments were 0.11-0.40, <0.05-0.98, 0.18-1.93 and 0.18-2.33 ng/g dry wt, respectively. Overall elevated levels of HCB, DDT and PCB were recorded at Babughat, a very closely located site of the metropolitan megacity Calcutta. Fluoranthene (flu) and pyrene (py), the dominant 4-ring PAHs, also showed an abrupt elevated concentrations at Babughat with values of 214 and 144 ng/g dry wt, respectively. Among the isomers and metabolites of HCH, DDT and PCB, alpha-HCH, pp'-DDT and PCB (101), PCB (118), PCB(153) and PCB (138) were found to be dominant. High ratios of metabolites of DDT to SigmaDDTs reveal recent use of DDT in this coastal environment. Fluoranthene, pyrene, 1,2-benzo(a)anthracene and chrysene formed the dominant congeners out of 19 identified PAHs. The sources of contamination are closely related to human activities such as domestic and industrial discharge, automobile exhausts, street runoff, slum sewage, agricultural chemicals and soil erosion due to deforestation as well as atmospheric transport. This study is compared to other coastal and estuarine environments in India and abroad. The baseline data can be used for regular ecological monitoring, considering the industrial and agricultural growth around this important estuarine ecosystem.     

Chlorinated biphenyls and pesticides in migrating and resident seabirds from East and West Antarctica

The unhatched eggs of the following seabirds were analyzed to quantify PCBs, hexachlorobenzene (HCB), α-, β-, γ-, δ-hexachlorocyclohexanes (HCHs), o,p' and p,p' isomers of DDT, DDD and DDE: resident Adèlie (Pygoscelis adèliae, ADPE) and Emperor (Aptenodytes forsteri, EMPE) penguins, migrating snow petrel (Pagodroma nivea, SNPT) and South Polar skua (Catharacta maccormicki, SPSK) from the Ross Sea (East Antarctica); and migrating Brown skua (Catharacta antartica, BRSK) and resident ADPE from the Brainsfield Strait (West Antarctica). The general aims were to evaluate the contaminant accumulation in eggs of migrating and resident species in the two study areas, and to compare levels in penguins and skuas nesting in East and West Antarctica. PCB congener and HCH and DDT isomer profiles were also assessed. Comparisons were evaluated using seven PCB congeners (IUPAC nos. 28, 52, 101, 118+149, 138, 153, and 180), p,p'-DDE, ΣDDTs, and ΣHCHs. Higher contaminant concentrations were detected in migrating seabirds (South polar skua and brown skua)>sub-Antarctic species (snow petrel)>Antarctic species (penguins) from both the sampling sites, suggesting contamination events at lower latitudes for those birds migrating northward. HCHs showed the lowest concentrations in all species (from 0.03±0.03 ng/g wet wt in SPSK to 1.81±1.23 ng/g wet wt in ADPE from West Antarctica), and PCBs were the most abundant contaminants (from 4.34±2.15 ng/g wet wt. in EMPE to 53.41±19.61 ng/g wet wt. in brown skua). Among pesticides, it is relevant the detection of p,p'-DDT in Adèlie penguin from West Antarctica and in both species of skua; the detection of this pesticide can confirm its actual use in certain malaria-endemic countries from where it is transferred through the long range transport to the polar regions. Contaminants did not show any significant temporal trend during a ten year time span, from 1994/95 to 2004/05, in organisms collected in East Antarctica and they did not indicate any latitudinal gradient along the Ross Sea coasts.     

Occurrence, distribution and possible sources of organochlorine pesticide residues in tropical coastal environment of India: an overview

Organochlorine pesticides (OCPs) are an important potential component of chemical pollutants used extensively for agriculture and sanitation purposes in India as these are comparatively cheap and effective. These persistent organic compounds such as HCH isomers, DDT and its metabolites are the predominant chemical contaminants found along the Indian coast and thus constitute both alluring and grave areas of scientific research. Our objective in the paper is to provide a comprehensive account of the distribution of organochlorine pesticides in biotic and abiotic compartments of the Indian coastal environment, make some comments on their environmental sources, their movement through the food chain and possible ecotoxicological risk of health in biota including humans. The prevalent HCH, DDT and HCB concentrations differ markedly in eastern and western coast of India reflecting differing agricultural and other usage and their ultimate input into the coastal environment by several rivers and the bioturbation activities of macrozoobenthos (bivalve mollusks, polychaetous annelids, etc.). In several cases, the DDT levels exceeded the effects range-low (ER-L) and could thus cause acute biological impairments, in comparison with the sediment quality guidelines. Contributions of DDT metabolites (DDT, DDD and DDE residues) vary in different Indian coastal regions predominated by pp'-DDT and pp'-DDD. Measured concentrations of HCHs were lower than DDTs that might be due to higher water solubility, vapor pressure and biodegradability of the latter. HCH and DDT residues in fish in India were lower than those in the temperate countries indicating a lower accumulation in tropical fish, which might be related to rapid volatilization of this insecticide in the tropical environment. The concentrations of other chlorinated pesticides (aldrin, dieldrin, eldrin, methoxychlor, endosulfan sulphate) were lower and not generally of great concern.     

Persistent organochlorine compounds in peregrine falcon (Falco peregrinus) eggs from South Greenland: levels and temporal changes between 1986 and 2003

Thirty-seven addled peregrine falcon eggs collected in South Greenland between 1986 and 2003 were analysed for their content of the organochlorine compounds polychlorinated biphenyls (PCBs), dichlorodiphenyl tricloroethane (DDT) and its degradation products, hexachlorocyclohexane (HCH) isomers and hexachlorobenzene (HCB). PCBs and DDT (including metabolites) were by far the most abundant OC groups, with median concentrations of 55 and 40 microg/g lw, respectively. The concentrations were high in an Arctic context, but similar to previously reported levels from Alaska and Norway and slightly lower than concentrations measured in eggs from industrialised regions. Geographical differences may be of importance, considering the migration of peregrine falcons and their prey. SigmaHCH and HCB had median concentrations of 0.39 and 0.17 microg/g lw, respectively. On average, DDE accounted for 97% of SigmaDDT, but was below critical levels for eggshell thinning. All compound groups showed a weak decreasing trend over the study period, which was statistically significant for HCB and close to being significant for SigmaHCH. The weak decrease of SigmaPCB and SigmaDDT is different from other time trend studies from Greenland, usually showing a more pronounced decrease in the beginning of the study period, followed by a certain stabilisation in recent years.     

Levels and distribution of organochlorines in fish from Indonesia

Organochlorines such as PCBs, DDTs, HCHs, CHLs and HCB were determined in pooled whole body homogenized of fish samples collected from five locations during 1998 and 2003 in order to understand their contamination status, temporal and spatial variation in Indonesian waters. PCBs and DDTs were the predominant contaminants with concentrations from 9.7 to 2700 ng/g lipid wt. and 12 to 1100 ng/g lipid wt., respectively, while HCHs (nd-24 ng/g lipid wt.), CHL compounds (nd-81 ng/g lipid wt.) and HCB (0.22-28 ng/g lipid wt.) were one to two orders of magnitude lower. Among the locations, PCBs and CHLs were higher in the samples from highly industrialized and thickly populated-locations, whereas OC pesticides such as DDTs and HCHs were particularly more prominent in suburban and rural areas. Levels of OCs observed in the waters surrounding Java Island were higher than those in Sumatra Island, implying significant use of OCs in highly populated Java Island. Concentrations of PCBs and DDTs in fish from Jakarta Bay were significantly lower in the samples collected in 2003 as compared to fish in 1998, indicating decreasing trend of these compounds in the Indonesian environment. Recent estimated average daily intakes of PCBs (0.81 microg/person/day), DDTs (1.1 microg/person/day), HCHs (0.018 microg/person/day), CHLs (0.010 microg/person/day) were much lower than the threshold values recommended by various agencies, suggesting minimal risk of this compound via fish ingestion to Indonesians.     

Distribution and fate of persistent organochlorine pesticides in coastal marine environment of Mumbai

Multi-compartment monitoring of residue levels of OCPs in coastal marine environment of Mumbai has been studied. The concentration of total HCHs in seawater varied from 0.16 to 15.92 ng/L and concentrations of total DDT varied from 3.01 to 33.21 ng/L. The total HCH concentration in the sediment samples was in the range of 3.8 to 16.2 ng/g. Gamma-HCH contributed almost 55% to the total HCH. In sediment samples the DDT has higher mean concentration in comparison to its metabolite DDE and DDD. The concentration of total HCHs in different marine species varied from 0.87 to 33.73 ng/g and concentrations of total DDT varied from 0.38 to 34.1 ng/g. The variation in the beta-HCH in different compartments is not significant and this could be due to the high persistence and metabolically inactive nature of this isomer. The alpha-HCH is found to be more dominant in fish samples whereas the gamma-HCH is major contributor in the sediment samples.