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.     

Inhibition of microbial activity of activated sludge by ammonia in leachate

Leachate samples were collected from the West New Territory Landfill (WENT), Hong Kong, and characterized in the laboratory. The analytical results confirmed that it has a typical nature of aged leachate with a low BOD₅/COD ratio of 0.22 and a high strength of ammonia-nitrogen around 5 g/L. A lab-scale study was conducted to investigate the inhibition of microbial activity of the activated sludge. In the first test, glucose-based synthetic wastewater was used in two parallel reactors. The experimental results demonstrated that COD removal declined from 95.1 to 79.1% and the dehydrogenase activity of the sludge decreased from 11.04 to 4.22 μg TF/mg mixed liquor suspended solids (MLSS), when the ammonia-nitrogen concentration increased from 50 mg/L to 800 mg/L progressively. The remaining NH₃⁺-N residue in the treated wastewater increased from 0.58 mg/L to 649 mg/L extensively. In the second test, mixed wastewater samples containing glucose and raw leachate were fed into six parallel biological reactors and operated on batch mode. The experimental results showed COD removal decreased from 97.7 to 78.1% and the dehydrogenase activity decreased from 9.29 to 4.93 μg triphenyl formazon (TF)/mg MLSS, respectively, when the ammonia-nitrogen concentration increased within the same range. Microbial inhibition could also be substantiated by a decrease of specific oxygen uptake rate (SOUR) from 68 to 45 mg O₂/g MLSS. These results suggested leachate containing high-strength ammonia-nitrogen should be pretreated to an acceptable NH₄⁺-N level before it is fed into biological reactors.     

淀山湖水生生物中有机氯化合物的浓度与富集特征

为研究淀山湖水生生物中有机氯化合物的浓度与富集特征,测定了该湖水生生物样品(铜锈环棱螺、日本沼虾、鱼类)中滴滴涕(DDTs)、六六六(HCHs)、六氯苯(HCB)、多氯联苯(PCBs)的浓度。研究结果显示,在所有生物样品中均检测到了DDTs、HCHs、HCB,各生物体内的有机氯农药含量有很大差异。在8种生物样品中,乌鳢体内的有机氯化合物含量最高,这可能与乌鳢处于较高营养级,且为肉食性鱼类,体内脂肪较多有关。∑DDTs、∑HCHs、HCB的含量范围分别是55~1 135、0.5~24、6.9~91ng/g lw,其中DDTs为最主要的有机氯农药。4,4’-DDE和α-HCH在各自同系物中所占比例最高,说明淀山湖历史上曾经使用过有机氯农药,而近期没有新的污染源输入。以铜锈环棱螺为参照,有机氯农药的生物放大系数(BMFs)范围是1.2(泥鳅)~23(乌鳢);PCBs的生物放大系数范围是5.9(河川沙塘鳢)~55(乌鳢)。亲脂疏水性、低生化降解速率导致有机氯化合物能在生物组织中富集并通过食物链逐级放大。研究结果表明,有机氯化合物会沿着食物链积累放大,可能会对人体健康存在潜在的威胁。     

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     

The contamination with organochlorine pesticides and heavy metals in surface water in Küçük Menderes River in Turkey, 2000-2002

This study was conducted from 2000 to 2002 to determine the residues of organochlorine pesticides (OCP) and metals in surface water of Kü?ük Menderes River in Turkey. The results showed that Kü?ük Menderes River was still polluted with organochlorine pesticide despite the existence of bans over a long time. The concentrations of pesticides depended on the sampling season and the tendency was not the same for all detected pesticides. The DDTs (DDT, DDD, DDE) were detected in most water samples. DDD showed a high concentration among DDTs. The highest concentration among organochlorine pesticides was heptachlor epoxide by 281 ng/l. However, the residues were lower than most polluted water from other sources in the world. In most cases, they were not detectable. The studied surface water metals varied from not detected to 0.258 mg/l, and the residues were low except for Ni, Cu, and Zn.     

Gas chromatographic/mass spectrometric analysis of partially dechlorinated 1,1-diphenyl ethane and ethylene

Gas chromatographic relative retention time data and 70 eV electron impact mass spectra of partially dechlorinated derivatives of 1,1-bis-p-chlorophenyl-2,2,2-trichloroethane (DDT), and the corresponding, 2,2-dichloroethylene (DDE) are presented.The mass spectra of all partially dechlorinated ethane intermediates are characterized by fragmentation across the aliphatic CC bond, whereas the mass spectra of the corresponding olefins are characterized principally by CCl bond rupture. The mass spectral data, coupled with the observed systematic decrease in relative retention time that is a function of aromatic chlorine substitution, provides an almost complete set of relative retention time data for the homologous series of compounds between both DDT and 1,1-diphenylethane and DDE and 1,1,-diphenylethylene.     

Prenatal DDT and DDE exposure and child IQ in the CHAMACOS cohort

Although banned in most countries, dichlorodiphenyl-trichloroethane (DDT) continues to be used for vector control in some malaria endemic areas. Previous findings from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort study found increased prenatal levels of DDT and its breakdown product dichlorodiphenyl-dichloroethylene (DDE) to be associated with altered neurodevelopment in children at 1 and 2 years of age. In this study, we combined the measured maternal DDT/E concentrations during pregnancy obtained for the prospective birth cohort with predicted prenatal DDT and DDE levels estimated for a retrospective birth cohort. Using generalized estimating equation (GEE) and linear regression models, we evaluated the relationship of prenatal maternal DDT and DDE serum concentrations with children's cognition at ages 7 and 10.5 years as assessed using the Full Scale Intelligence Quotient (IQ) and 4 subtest scores (Working Memory, Perceptual Reasoning, Verbal Comprehension, and Processing Speed) of the Wechsler Intelligence Scale for Children (WISC). In GEE analyses incorporating both age 7 and 10.5 scores (n = 619), we found prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales (p-value > 0.05). In linear regression analyses assessing each time point separately, prenatal DDT levels were inversely associated with Processing Speed at age 7 years (n = 316), but prenatal DDT and DDE levels were not associated with Full Scale IQ or any of the WISC subscales at age 10.5 years (n = 595). We found evidence for effect modification by sex. In girls, but not boys, prenatal DDE levels were inversely associated with Full Scale IQ and Processing Speed at age 7 years. We conclude that prenatal DDT levels may be associated with delayed Processing Speed in children at age 7 years and the relationship between prenatal DDE levels and children's cognitive development may be modified by sex, with girls being more adversely affected.     

Breast cancer incidence and exposure to pesticides among women originating from Jaipur

Environmental contamination by pesticides has been documented in biotic and abiotic components. These persistent organic pollutants are lipid soluble, nonbiodegradable, and endocrine disrupters. The present study was therefore planned to determine whether the levels of these pesticides like DDT and its metabolites DDD and DDE, dieldrin, heptachlor, and HCH and its isomers (alpha, beta, and gamma) were higher in blood of breast cancer patients when compared with normal women who did not suffer from major diseases like blood pressure, tuberculosis, diabetes, thyroid dysfunction, arthritis, cancer, etc. and had not undergone any major surgery. The results indicated that organochlorine pesticides taken for analysis were found significantly high in breast cancer patients irrespective of age, diet, and geographic distribution.     

Evaluation of the aerobic biodegradation of trichloroethylene via response surface methodology

Response surface methodology (RSM) was used to evaluate the effect of additives for enhancing the aerobic biodegradation of trichloroethylene (TCE). The parameters investigated include the initial TCE concentration, addition of extra bacteria, use of toluene as an inducer and hydrogen peroxide as terminal electron acceptor (TEA). Without additive, degradation efficiencies of >or=80% were obtained for TCE concentrations<700 mg/L. According to the second-order polynomial RSM and biodegradation results, the use of toluene to induce enzyme production inhibited degradation at TCE concentrations<300 mg/L. The addition of hydrogen peroxide did improve the overall degradation efficiency but decreased the degradation rate. The RSM model for toluene, extra bacteria and TEA predicted that the best approach to optimize degradation of high TCE concentrations is to ensure adequate population in conjunction with supplemental TEA.     

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.     

Assessment of organochlorine pesticide residue levels in dairy milk and buffalo milk from Jaipur City, Rajasthan, India

The widespread application of pesticides in agriculture, public health, and industry and in and around the home can result in the accumulation of pesticides in the environment. Therefore, a survey has been conducted during 1993-1996 to investigate the magnitude of contamination of bovine milk with organochlorine pesticide (OCP) residues from Jaipur City, Rajasthan, India. Milk samples, i.e., dairy (toned and whole) and buffalo milk, were collected seasonally, and pesticide residues were assessed using a gas chromatograph (GC) with an electron capture detector (ECD). The results indicate that all the milk samples were contaminated with dichlorodiphenyltrichloroethane (DDT) and its metabolites (DDE and p,p'-dichlorodiphenyldichloroethane [DDD]), isomers of hexachlorocyclohexane (HCH; alpha, beta, and gamma), heptachlor and its epoxide, and aldrin. Seasonal variations of these pesticide residue levels were also observed in all the milk samples. Samples collected during winter season were found to contain higher residue levels as compared to other seasons.     

长江口九段沙水域有机氯农药分布

对九段沙（HCHs）水域采集滩涂水样以及沉积物，进行GC-ECD检测，研究有机氯农药的分布。结果表明，九段沙水域水体中六六六含量为6．6～17．1ng／L，平均值9．93ng／L，滩涂沉积物中的六六六含量为2．32～6．30ng／g；九段沙水域水体中滴滴涕（DDTs）含量4．99～46．6ng／L，平均值为18．53ng／L，滩涂泥样中的滴滴涕（DDTs）含量5．9～70．83ng／g。从异构体成分分析，九段沙水域受到了陆上林丹使用的影响，但是东海海水的冲刷能降低林丹所占六六六含量的比例；另外滴滴涕则显示较早期的污染，表现为代谢物（DDD和DDE）含量较高的现象，同时调查发现该水域在近期可能有滴滴涕输入。     

Further studies on the influence of zeolite type A on metal transfer in the activated sludge process

Investigations were carried out to determine the effect of zeolite type A on metal removal by activated sludge using laboratory activated sludge simulations. They were operated at constant aerator sludge age and settler surface loading. Different concentrations of raw zeolite and zeolite extracted from washing powder (0, 15, 30, 60, 120 mgl^?1) were introduced into the simulations. The zeolite was added at two degrees of calcium exchanged for sodium, 25 and 75% of the maximum exchange capacity. Metals were added at concentrations typical of mixed domestic-industrial waste waters. The results show that there was no adverse effect on metal removal by the laboratory activated sludge simulations in the presence of zeolite type A.     

DDT and HCH residue load in mother's breast milk: a survey of lactating mother's from remote villages in Agra region

Breast milk is the natural and optimal food for the infants. In addition to meeting the nutritional needs, breast milk provides numerous immunological, developmental, psychological, ecological and practical advantages. The levels of the DDT and HCH residues in human milk collected from remote rural part of Agra were analysed. Beta and gamma isomers of HCH accounts for the major residue of total HCH excreted in breast milk. Delta-HCH was not detected in the samples. 95% of the samples were found to be contaminated with DDT and its metabolites. DDD was found in 88% of the samples analyzed. The total concentration of DDT and HCH were found lower than the previous studies carried out in India. The study shows the decreasing levels of these organochlorine pesticides from the environment. Total concentration of total DDT is higher than total HCH.     

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.     

Development of extraction method of pharmaceuticals and their occurrences found in Japanese wastewater treatment plants

In this study, occurrence of 66 PPCPs (pharmaceuticals and personal care products) in liquid and solid phases of sewage sludge was elucidated. The extraction methods for the PPCPs from sludge were newly developed employing Pressurized Liquid Extraction (PLE) and Ultrasonic Solvent Extraction (USE). As an appropriate method, PLE using water (pH2), PLE using methanol (pH4), and USE using mixture of methanol and water (1/9,v/v, pH11) was found most effective because total recovery of most of the PPCPs indicated 40 to 130%. The developed extraction method with previously developed method for liquid phase analysis was applied to field survey at wastewater treatment plants (WWTPs) in Japan. 56 compounds were detected from the primary sludge and 61 compounds were detected from the excess sludge. The concentration was ranged between several ng/g and several μg/g. Solid-water distribution coefficient (Log K_d) ranged between 0.9 L/kg (Caffeine) and 3.7 L/kg (Levofloxacin) for primary sludge and between 1.4 L/kg (Sulpirid) and 4.3 L/kg (Mefenamic acid) for excess sludge.     

Removal of nutrients and heavy metals from anaerobic waste by aerobiological treatment

This study was conducted to investigate the effectiveness of aerobic biological treatment in removal of nitrogen, phosphorous, and heavy metals from a unique anaerobic liquid waste, produced at a solid waste-to-methane anaerobic digestion facility. Laboratory scale continuous flow activated sludge reactors were employed in this study. The liquid waste has moderate BOD/COD ratio with BOD concentration of 1300 mg/L and high concentration of essential nutrients, making the liquid waste biologically treatable. Results showed that aerobic biological treatment can remove nitrogen and phosphorous on the order of 85%. Metal removal efficiencies vary widely for 11 metals studied in this investigation.     

Triclosan in wastewaters and biosolids from Australian wastewater treatment plants

Triclosan (TCS) is an antimicrobial agent widely used in many personal care products. This study investigated the occurrence of TCS in effluents, biosolids and surface waters, and its fate in wastewater treatment plants (WWTPs). The aqueous concentrations of TCS in nineteen effluents from Australian WWTPs ranged from 23 ng/L to 434 ng/L with a median concentration of 108 ng/L, while its concentrations in nineteen biosolids ranged from 0.09 mg/kg to 16.79 mg/kg on dry weight basis with a median concentration of 2.32 mg/kg. The removal rates for TCS in five selected WWTPs were found to range between 72% and 93%. Biological degradation was believed to be the predominant removal mechanism for TCS in the WWTPs. However, adsorption onto sludge also played a significant role in the removal of TCS in the WWTPs. TCS at concentrations up to 75 ng/L was detected in surface waters (outfall, upstream, and downstream) from five rivers receiving effluent discharge from WWTPs. Preliminary risk assessment based on the worst-case scenario showed that the TCS concentrations in surface waters might lead to risks to aquatic organisms such as algae. Based on the TCS levels in the biosolids, application of biosolids on agricultural land may also cause adverse effects in the soil environment.     

Biodegradation of phthalic acid esters by acclimated activated sludge

The microbial degradation by acclimated activated sludge of three phthalates, priority pollutants listed by both the China National Environmental Monitoring Centre and the U.S. EPA, i.e., dimethyl (DMP), di-n-butyl (DBP), and di-n-octyl (DOP) phthalate was investigated. The experimental results demonstrated that DMP and DBP with the shorter alkyl-side chain phthalic acid esters (PAEs) can be rapidly degraded—nearly 90% within 3 d for DMP and 8 d for DBP. However, the degradation rate of DOP was slow. The degradation of PAEs can be described by the first-order reaction model. The first-order rate constants (k₁) of three PAEs determined in this study can correlate with the corresponding second-order hydrolysis rate constants (K_OH).     

富氧生物膜法修复微污染水源的机理研究

采用弹性立体填料、微孔曝气富氧生物接触氧化法修复上海市受污染的川杨河水,生物填料在进水氨氮浓度2.6～3.1 mg/L和水温20℃～22℃下,7 d自然挂膜培养成功, 氨氮去除率达90%以上。 生化池运行一段时间后,必须根据生物膜厚度和其除污染效率,适时适度冲洗填料和排除池底积泥,以防止好氧生物膜出现厌氧运行状况和影响除污染效果。在川杨河水源水质浊度90～300 NTU、 NH+4-N 0.5～10.0 mg/L、CODMn4.0～10.8 mg/L、污染指数为2～8及生物修复工艺HRT为1.3 h、DO为7.5～10.2 mg/L、g/w为0.5/1的正常运行条件下,观察到膜上的生物相丰富, 微生物种类繁多, 主要是好氧的异养菌和自养菌。生物膜较薄,一般厚度为0.09～0.13 mm,在原水污染物氨氮浓度较低,曝气充足,水中溶解氧浓度高,好氧生物膜传质阻力小、速度快,污染物氨氮的生物降解速率很快,只需较短的水力停留时间,就能达到很高的氨氮去除率。微孔曝气气液传质充分,水中溶解氧充足,膜内无厌氧层存在。好氧生物膜内处于完全的好氧状态,硝化反应比较完全。污染的去除主要是填料上的好氧生物膜在起作用。