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1.

Purpose

??-Hexachlorocyclohexane (HCH), ??-HCH, and lindane (??-HCH) were listed as persistent organic pollutants by the Stockholm Convention in 2009 and hence must be phased out and their wastes/stockpiles eliminated. At the last operating lindane manufacturing unit, we conducted a preliminary evaluation of HCH contamination levels in soil and water samples collected around the production area and the vicinity of a major dumpsite to inform the design of processes for an appropriate implementation of the Convention.

Methods

Soil and water samples on and around the production site and a major waste dumpsite were measured for HCH levels.

Results

All soil samples taken at the lindane production facility and dumpsite and in their vicinity were contaminated with an isomer pattern characteristic of HCH production waste. At the dumpsite surface samples contained up to 450?g?kg?1 ?? HCH suggesting that the waste HCH isomers were simply dumped at this location. Ground water in the vicinity and river water was found to be contaminated with 0.2 to 0.4?mg?l?1 of HCH waste isomers. The total quantity of deposited HCH wastes from the lindane production unit was estimated at between 36,000 and 54,000?t.

Conclusions

The contamination levels in ground and river water suggest significant run-off from the dumped HCH wastes and contamination of drinking water resources. The extent of dumping urgently needs to be assessed regarding the risks to human and ecosystem health. A plan for securing the waste isomers needs to be developed and implemented together with a plan for their final elimination. As part of the assessment, any polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) generated during HCH recycling operations need to be monitored.  相似文献   

2.
Abhilash PC  Singh N 《Chemosphere》2008,73(6):1011-1015
Concentrations of hexachlorocyclohexane isomers (alpha-HCH, beta-HCH, gamma-HCH, and delta-HCH) were studied in soils samples collected from a small scale industrial unit of Lucknow associated with lindane production. All four isomers were detected from ten sites and the total HCH isomers in the analyzed samples varied from 53 to 99mgkg(-1). Cluster analysis was performed to group the soil sites in terms of their HCH contamination level. Low alpha/gamma HCH ratios were found and they indicate recent input of HCH. There is an urgent need for the on-site remediation of these contaminated sites in order to prevent the long-term environmental pollution.  相似文献   

3.
Mean hexachlorobenzene (HCB) and hexachlorocyclohexane (HCH) concentrations, measured in seawater and air samples, confirmed the decline in levels of these compounds in Antarctic air and water. However, low α/γ-HCH ratios in air at the beginning of the sampling period suggest a predominance of fresh lindane entering the Antarctic atmosphere during the Austral spring probably due to current use in the Southern Hemisphere. Water-air fugacity ratios demonstrate the potential for HCH gas deposition to coastal Antarctic seas, while the water-air fugacity ratios for HCB imply that volatilization does not account for the observed decrease of HCB in surface seawater. HCH concentrations found in krill samples were correlated with seawater concentrations indicative of bioconcentration of HCHs from seawater.  相似文献   

4.
A new approach for the removal of the pesticide lindane (gamma-hexachlorocyclohexane or gamma-HCH) makes use of catalytic reduction of HCH to benzene over a metal catalyst, namely Pd(0). Since specific surface area plays an important role in reactivity of catalysts, this study investigated the use of bioPd(0), i.e. nano-scale Pd(0) particles precipitated on the biomass of Shewanella oneidensis, for the removal of lindane. It was demonstrated that bioPd(0) has catalytic activity towards dechlorination of gamma-HCH, with the addition of formate as electron donor, and that dechlorination with bioPd(0) was more efficient than with commercial powdered Pd(0). The biodegradable compound benzene was formed as reaction product and other HCH isomers could also be dechlorinated. Subsequently bioPd(0) was implemented in a membrane reactor technology for the treatment of gamma-HCH polluted water. In a fed-batch process configuration with formate as electron donor, a removal percentage of 98% of gamma-HCH saturated water (10 mg l(-1)) was achieved within 24h. The measured chloride mass balance approached the theoretical value. The results of this work showed that a complete, efficient and fast removal of lindane was achieved by biocatalysis with bioPd(0).  相似文献   

5.
The inhibitory potencies of BHC isomers against Na+-K+- ATPase, yeast growth and nerve conduction of the American cockroach were determined. The insecticidal and neuroexcitatory activities of a number of analogs with the same configuration as lindane in which some chlorine atoms had been replaced by other substituents were also examined against American cockroaches. The structure-activity relationships and the mode of action of lindane and its analogs were discussed. Their metabolic fate was studied extensively in vivo as well as in vitro. The critical step in the biodegradation of lindane is the cleavage of C-H bonds which we found by utilizing the isotope effect of hexadeuterated lindane.  相似文献   

6.
Spatial distribution of lindane in topsoil of Northern France   总被引:1,自引:0,他引:1  
Lindane is a persistent organochlorine insecticide and the use of this insecticide in agriculture was banned in France in 1998. In this study we investigated the concentrations of lindane in topsoil in Northern France and used robust geostatistics to map the geographical distribution of lindane. The study was based on a 16 km × 16 km grid covering an area of ca 25 000 km2. Lindane was found in all soils, even those from non-agricultural-application areas. Very low ratios of α-/γ-HCH and δ-/γ-HCH suggested that a long time had passed since technical HCH was used in the studied area, or that emission sources of lindane were still present. A strong gradient in lindane concentration was observed, with the highest lindane concentrations in an area located in the northern region. Results suggested that some of the lindane observed in the high concentration area may have come from volatilization of old lindane applied to intensively cultivated areas, which was then transported by prevailing winds coming from the south-west and deposited in a densely inhabited depression.  相似文献   

7.
Hexachlorocyclohexane (HCH) isomers (α-, β- and γ- HCH [lindane]) were recently added to the list of persistent organic pollutants regulated by the Stockholm Convention, and therefore, the legacy of HCH and lindane production has become an issue of global relevance. The production of lindane with the much larger quantities of associated waste isomers has generated large waste deposits and contaminated sites. This article presents an overview of HCH-polluted sites in Brazil as a basis for further activities related to the Stockholm Convention. The locations of HCH stockpiles and contaminated sites in Brazil arising from production and formulation have been compiled and mapped. This shows that the measures taken over the past 25 years have not resulted in remediation of the HCH pollution. An exposure risk study has been summarised for one major site and is included to demonstrate the contemporary relevance of the contamination. Major site remediation efforts are planned at one site but people live close to several other sites, and there is an urgent need of further assessments and remediation to ensure the protection of human health and the environment. The Stockholm Convention requires a systematic approach and should be adopted for the assessment of all sites and appropriate isolation/remediation measures should be facilitated. The appropriate planning of these activities for the production site in Rio de Janeiro could be a positive contribution for Rio+20 highlighting that green economy and sustainable production also include the appropriate management of legacies of historic production of an industrial sector (here the organochlorine industry).  相似文献   

8.
Abstract

The wood charcoal treated by 1N HNO3 (WCT) was used to remove toxic chlorinated pesticide lindane (y‐HCH) residue from water by the sorption process. Using a simple first order reversible kinetics constants and half time equations, the film and pore diffusion coefficients were determined. Film diffusion was found to be rate limiting step in sorbing lindane by WCT. This was further authenticated by kinetics studies at different initial sorbate concentrations, different sorbent sizes, and different agitation speeds besides interruption test. A pore diffusion model was used to fit the data of kinetics in continuously mixed batch reactors (CMBR), and the tortuosity, external resistance, and surface diffusion effects on lindane sorption by WCT were noticed. The tortuosity values of 15 to 28 were obtained for WCT‐lindane system.  相似文献   

9.
In 2009, hexachlorocyclohexane (HCH) isomers (α-HCH, β-HCH, and γ-HCH [lindane]) were listed as persistent organic pollutants (POP) in the Stockholm Convention. Accordingly, the legacy of HCH/lindane production with the associated large HCH waste deposits has become recognized as an issue of global concern and is addressed in the implementation of the Convention. The current paper gives an overview of the major contaminated sites from lindane production of the INQUINOSA Company. This company operated from 1975 to 1988 in the city of Sabiñánigo, Spain. HCH production resulted in the production of approximately 115,000 tonnes of waste isomers which were mainly dumped in two unlined landfills. These two landfill sites, together with the former production site, are recognized sources of environmental pollution. Assessment and remediation activities at these sites are described. A dense nonaqueous phase liquid (DNAPL) contaminated inter alia with HCH isomers, benzene, chlorobenzenes, and chlorophenols as the main contaminants and an associated contaminated groundwater plume have been discovered at both landfill/dumpsites and at the former production site. The approximately 4,000 t of DNAPLs constitute a serious risk for the environment due to the proximity of the Gállego River. Since 2004, more than 20 tonnes of this DNAPL has been extracted using “pump and treat” techniques. The Aragon Regional Government and the Spanish Environmental Ministry are taking action, focusing on the treatment of DNAPL and on the transfer of the large quantities of solid POP wastes to a new landfill. A range of laboratory tests has been performed in order to plan the aquifer remediation.  相似文献   

10.
Persistent organochlorines such as polychlorinated biphenyls (PCBs), DDTs, chlordane compounds (CHLs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were determined in the blubber of minke whale and its diet collected from the Antarctic and the North Pacific Oceans. Residue levels of these compounds (except HCB) in minke whale from the Antarctic were apparently lower than those from the North Pacific. This is due to the lower levels of these pollutants in the southern hemisphere than in the northern hemisphere and the specific feeding habit of the minke whale from the Antarctic which feeds on lower trophic organisms, primarily euphausiids. The north-south difference for HCB residue levels was small, reflecting its dispersible nature through long-range atmospheric transport. Compositions of DDT and CHL compounds in minke whale from the Antarctic were similar to those from the North Pacific. However, the composition of HCH isomers was different between the Antarctic and the North Pacific as was observed in their diet, suggesting a larger or on-going usage of lindane in the southern hemisphere countries. In minke whale from the Antarctic, the elevated level of PCBs residues was noted during a period of 1984 to 1993, implying a continuous discharge of PCBs in the southern hemisphere. A similar discharge was also suggested in the North Pacific, while a decreasing contamination by DDTs was apparent.  相似文献   

11.
Previously unreported metabolites from the urine of rats treated with lindane have been identified as configurational isomers of 2,4,5,6- and 2,3,4,6-tetrachloro-2-cyclohexen-1-ol. In addition, an intermediate metabolite from the incubation of lindane with liver preparations, under N2, has been identified as the configurational isomer γ-3,4,5,6-tetrachlorocyclohex-1-ene. The pathways leading to these metabolites appear to have an important role in the metabolism of lindane by mammals.  相似文献   

12.
The Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) method was applied to the extraction of 14 organochlorine pesticides (OCPs) residues from commercial fruit pulps available in supermarkets in Fortaleza, Northeastern Brazil. The analyses were carried out by gas chromatography (GC), coupled to an electron-capture detector (ECD), and were confirmed by GC-tandem mass spectrometry (MS). The parameters of the analytical method, such as accuracy, precision, linear range, limits of detection and quantification, were determined for each pesticide. The results showed good linearity (R2 ≥ 0.9916) and the overall average recoveries were considered satisfactory obtaining values between 69 and 110%, RSD of 2–15 %, except for hexachlorobenzene (HCB) in açai, acerola and guava pulp samples. The OCPs were detected in guava (α–HCH; lindane) and soursop (α, β–HCH isomers) samples. The QuEChERS method and GC–ECD were successfully used to analyze OCPs in commercially available Brazilian fruit pulps and can be applied in routine analytical laboratories.  相似文献   

13.
α-HCH, β-HCH, and γ-HCH (lindane) were listed as persistent organic pollutants in the Stockholm Convention. Therefore, they need to be globally addressed including the wastes remaining from historic use and production. While at most lindane production sites the unintentionally produced 85 % HCH waste isomers have been deposited, at a former pesticide factory in Hamburg-Moorfleet HCH waste isomers have been recycled from 1953 to 1984 by thermal decomposition to chlorobenzenes and resulted in high polychlorinated dibenzo-p-dioxin/polychlorinated dibenzofuran (PCDD/PCDF)-contaminated residues. The management of the PCDD/PCDF-contaminated waste from the former pesticide factory in Hamburg has been assessed and quantified. Based on past accredited PCDD/PCDF measurements, the registered 3,700 tonnes of disposed thermal HCH decomposition residue contained 333 to 854 kg of PCDD/PCDF toxicity equivalent (I-TEQ) in 53–102 tonnes total sum of PCDD/PCDF. The wastes have been deposited together with other wastes in landfills in Hamburg and other parts of Germany. For the Georgswerder landfill (Hamburg), where approximately 50 % of the PCDD/PCDF is disposed, current and previous situation and remediation activities are described. While PCDD/PCDF leaching from the landfill is controlled and incinerated, more water soluble organochlorines (vinyl chloride, cis-1,2-dichlorethene, chlorobenzenes) and benzene remain as a challenge for groundwater management. A comprehensive aftercare program has been established and will need to be operated by future generations including renewal of containment systems. Former lindane/HCH productions need—in addition to HCH deposits—to be assessed for possible recycling practice of HCH and related PCDD/PCDF-containing deposits. This could systematically be addressed within the Stockholm Convention implementation.  相似文献   

14.
α-Hexachlorocyclohexane (HCH), β-HCH, and γ-HCH (lindane) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention. Therefore, the chemicals need to be globally addressed, including the disposal of historic wastes. At most sites, the approximately 85 % of HCH waste isomers were dumped. At a former lindane factory in Hamburg and some other factories the HCH, waste was recycled producing residues with high polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) levels. The soil and ground water under the former pesticide factory was/is highly contaminated with HCH (260 tons), chlorobenzenes (550 tons), and PCDD/PCDF (6 kg toxic equivalents (TEQ)). This contamination did not result from disposal operations but from spillages and leakages during the 30 years of the factory's production history. A containment wall has been constructed around the production area to prevent the dispersal of the pollutants. The ground water is managed by a pump and treat system. Over the last 15 years, approximately 10–30 tons of this pollution reservoir has been pumped and incinerated. For the contaminated production buildings, specific assessment and demolition technologies have been applied. In addition to their HCH waste isomer deposition, former lindane/HCH productions need to be assessed for possible recycling practice of HCH and related PCDD/PCDF contamination of the production area and buildings. Since such recycling activities have taken place at several factories in different countries, the experience of assessment and management of the described production area and contaminated buildings could be valuable. Such assessment could be addressed within the frame of the Stockholm Convention.  相似文献   

15.
We use air mass back trajectory analysis of persistent organic pollutant (POP) levels monitored at a regional background site, Ko?etice, Czech Republic, as a tool to study the effectiveness of emission reduction measures taken in the last decade in the region. The representativity of the chosen trajectory starting height for air sampling near ground was ensured by excluding trajectories starting at time of inversions lower than their starting height. As the relevant pollutant sources are exclusively located in the atmospheric boundary layer, trajectory segments above this layer were also excluded from the analysis. We used a linear time weight to account for the influence of dispersion and deposition on trace components abundances and to quantify the ground source loading, a continuous measure for the influence of surface emissions. Hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), DDT, and two time periods, the years 1997–1999 and 2004–2006, were studied. The pollutant levels transported to Ko?etice decreased for all substances except HCB. Except for lindane seasonal emissions were insignificant. Increasing emissions of HCB were at least partly linked to the 2002 floods in the Danube basin. Major emissions of 1997–1999 which decreased significantly were in France (lindane), western Poland, Hungary and northern ex-Yugoslavia (technical HCH), and the Czech Republic (DDT). Emissions remaining in 2004–2006 include HCB and DDT in the northern Czech Republic, HCB and PCBs in Germany. Besides changes in emission strength meteorological factors influence the level of transported pollutant concentrations. The prevailing air flow pattern limits the geographic coverage of this analysis to central Europe and parts of western Europe. However, no POP monitoring stations exist in areas suitable for a possible extension of the study area.  相似文献   

16.
To categorize the marine environmental health status, the Oslo and Paris commissions have recently formulated Ecological Quality Objectives (EcoQOs) for many ecological features including the contamination of coastal bird eggs with mercury and organochlorines. In this study, we describe spatial and temporal patterns of egg contamination around the North Sea and compared them to the EcoQOs. Concentrations of mercury, polychlorinated biphenyl (??PCB) congeners, dichlorodiphenyltrichloroethane (??DDT) and derivatives, hexachlorobenzene (HCB) and hexachlorocyclohexane (??HCH) isomers were analysed in two tern species (Sterna hirundo and Sterna paradisaea) and Oystercatcher (Haematopus ostralegus) eggs collected between 2008 and 2010 in a total of 21 sites in seven countries surrounding the North Sea. Hg, ??PCB and HCB were highest in the southern sites, while ??DDT and ??HCH concentrations were greatest in eggs from the western North Sea and the Elbe estuary. There were rarely any consistent decreases over time for any compounds. In the terns, Hg, HCB and ??HCH increased at most sites, ??PCB and ??DDT in Sweden and Norway. In the Oystercatcher, HCB and ??HCH increased at more than the half of the sites, ??PCB, ??DDT and Hg at several German sites. In the terns, Hg, ??PCB and ??DDT exceeded the EcoQO in all, HCB in most years and sites. At most sites, ??HCH fulfilled the EcoQO in some study years. In the Oystercatcher, Hg, ??PCB and ??DDT exceeded the EcoQO in all or most years and sites. HCB and ??HCH fulfilled the EcoQO in some or all years at most sites. The EcoQO was exceeded most frequently in estuaries. We conclude that EcoQOs are suitable for drawing contamination patterns of the coastal North Sea in an easily understandable manner, offering the opportunity to harmonize the EcoQOs with coordinated environmental monitoring programmes.  相似文献   

17.
This study is focused on the effective removal of recalcitrant pollutants hexaclorocyclohexanes (HCHs, isomers α, β, γ, and δ) and chlorobenzenes (CBs) present in a real groundwater coming from a landfill of an old lindane factory. Groundwater is characterized by a total organic carbon (TOC) content of 9 mg L?1, pH0?=?7, conductivity?=?3.7 mS cm?1, high salt concentration (SO42?, HCO3?, Cl?), and ferrous iron in solution. The experiments were performed using a BDD anode and a carbon felt (CF) cathode at the natural groundwater pH and without addition of supporting electrolyte. The complete depletion of the four HCH isomers and a mineralization degree of 90% were reached at 4-h electrolysis with a current intensity of 400 mA, the residual TOC (0.8 mg L?1) corresponding mainly to formic acid. A parallel series reaction pathway was proposed: HCHs and CBs are transformed into chlorinated and hydroxylated intermediates that are rapidly oxidized to non-toxic carboxylic acids and/or mineralized, leading to a rapid decrease in solution pH.  相似文献   

18.
Gamma-hexachlorocyclohexane (gamma-HCH or lindane), one of the most commonly used insecticides, has been mainly used in agriculture. Organochloride compounds are known to be highly toxic and persistent, causing serious water and soil pollution. The objective of the present study is the evaluation of the anaerobic degradation of alpha-, beta-, gamma-, delta-HCH in liquid and slurry cultures. The slurry system with anaerobic sludge appears as an effective alternative in the detoxification of polluted soils with HCH, as total degradation of the four isomers was attained. While alpha- and gamma-HCH disappeared after 20-40d, the most recalcitrant isomers: beta- and delta-HCH were only degraded after 102d. Intermediate metabolites of HCH degradation as pentachlorocyclohexane (PCCH), tetrachlorocyclohexene (TCCH), tri-, di- and mono-chlorobenzenes were observed during degradation time.  相似文献   

19.

Background, aim, and scope  

Lindane, technically 1, 2, 3, 4, 5, 6-hexachlorocyclohexane (γ- HCH), is the most commonly detected organochlorine pesticide from diverse environmental compartments. Currently, India is the largest consumer and producer of lindane in the world. The production of lindane results in the generation of large quantities of waste HCH isomers (mainly α-, β- and δ-). All these isomers are toxic and have a long-range environmental transport potential. The aim of this study was to monitor the seasonal variation of HCH isomers in an open soil–plant–rhizospheric soil system of a contaminated industrial area. For this, selected plant species and their rhizospheric soil (soil samples collected at a depth range of 0–45 cm near to the root system) and open soil samples (soil samples collected (0–30 cm depth) from 1–1.5 m away from the plant root system) were collected for 2 years (two summer seasons and two winter seasons).  相似文献   

20.
The insecticide gamma-hexachlorocyclohexane (gamma-HCH or lindane), which has been extensively used for agricultural and medical purposes, presents high persistence and toxicity to the environment and low solubility. This study intends to assess the efficiency of an anaerobic reactor to degrade HCH isomers contained in soil slurry cultures. This study was developed in two phases: experiments in flasks to optimize the process parameters, and assessment of the slurry process in the anaerobic slurry reactor operated for an approximate period of a year. The influence of different environmental conditions was evaluated: the HCH concentration (25-100 mg HCH kg-1), the type of substrate (volatile fatty acids or starch), the sludge concentration (2-8 g VSS l-1) and the replacement of spiked soil to simulate a fed-batch operation (10-50%). The best results were obtained when the reactor was operated with a sludge concentration of 8 g VSS l-1, starch concentration of 2 g COD l-1 and soil replacements of 10-20%. Under these conditions, alpha- and gamma-HCH were completely degraded after 10d while nearly 90% beta- and delta-HCH were removed only after 50 d. According to the obtained results related to the total degradation of the HCH isomers and the degradation rates, especially high for alpha- and gamma-HCH, the anaerobic slurry reactor appears to be a good alternative for the degradation of the HCH isomers present in polluted soil.  相似文献   

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