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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.

Purpose

Hexachlorocyclohexane (HCH) isomers (??-, ??- and ??- (Lindane)) were recently included as new persistent organic pollutants (POPs) in the Stockholm Convention, and therefore, the legacy of HCH and Lindane production became a contemporary topic of global relevance. This article wants to briefly summarise the outcomes of the Stockholm Convention process and make an estimation of the amount of HCH waste generated and dumped in the former Lindane/HCH-producing countries.

Results

In a preliminary assessment, the countries and the respective amount of HCH residues stored and deposited from Lindane production are estimated. Between 4 and 7 million tonnes of wastes of toxic, persistent and bioaccumulative residues (largely consisting of alpha- (approx. 80%) and beta-HCH) are estimated to have been produced and discarded around the globe during 60 years of Lindane production. For approximately 1.9 million tonnes, information is available regarding deposition. Countries are: Austria, Brazil, China, Czech Republic, France, Germany, Hungary, India, Italy, Japan, Macedonia, Nigeria, Poland, Romania, Slovakia, South Africa, Spain, Switzerland, Turkey, The Netherlands, UK, USA, and former USSR. The paper highlights the environmental relevance of deposited HCH wastes and the related POPs?? contaminated sites and provides suggestions for further steps to address the challenge of the legacy of HCH/Lindane production.

Conclusion

It can be expected that most locations where HCH waste was discarded/stockpiled are not secured and that critical environmental impacts are resulting from leaching and volatilisation. As parties to the Stockholm Convention are legally required to take action to stop further POPs pollution, identification and evaluation of such sites are necessary.  相似文献   
3.
Petroleum ether extracts of leaves, stem and inflorescence of Parthenium hysterophorus Linn. at 500, 1000, 2000 and 5000 ppm concentrations were tested in the laboratory for their toxic effects on the mean life span and progeny production of adults of the mustard aphid, Lipaphis erysimi (Kalt.). The investigations revealed a significant decrease in life span and progeny production with treatment. Among the three plant parts tested for their efficacy, the leaf extract showed the most significant effect in causing a dose dependent decline in both the life span and progeny production.  相似文献   
4.
Changes in the principal sources of Pb in overbank sediment profiles have been documented for two Spanish areas by using Pb isotopes and Pb concentrations. These locations (Madrid and Tinto–Odiel basin) represent two of the most contaminated regions in Spain. The Community of Madrid is characterized by heavy industrial and urban activity, focused mainly in Madrid City. The Tinto–Odiel basin drains the Iberian Pyrite Belt, which hosts many polymetallic massive sulphides and is heavily affected by mining activities in their headwaters. It has been proven that the influence of anthropogenic activity is reflected in these overbank deposits by variations in Pb concentrations that, in general, correlate with shifts in the 206Pb/207Pb ratio. Rivas profile (downstream of Madrid) was found to be the most anthropogenically influenced site. The sediments within this profile which were recently deposited (170 ± 40 years BP) have the least radiogenic signatures. 206Pb/207Pb ratios ranged between 1.1763 and 1.1876 indicating significant contributions of anthropogenic Pb. In contrast, profiles upstream of Madrid possess an average 206Pb/207Pb ratio of 1.2272. It is difficult to clearly identify the most prominent source as the sediments appear to be characterized by an input from several sources. The floodplain profiles in the Tinto–Odiel basin exhibit uniform 206Pb/207Pb ratios ranging from 1.1627 (Odiel river) to 1.1665 (Tinto river). These ratios are similar to the ones possessed by sulphide ores in the area and differ from the ratios of other nonmineralized formations in the basin, indicating that mining activities are the primary, if not sole, source of Pb to the sediments.  相似文献   
5.
The enzymatic activity of five enzymes viz. Glutathione S-transferases, Esterases, NADH dehydrogenase, NADH oxidase and Glutathione reductase were assessed under the influence of Indole butyric acid (IBA) (400 ppm) in the nymphs (48-52h old) of mustard aphid, Lipaphis erysimi fed on radish plants treated for 13, 25 and 37h. The activity of Glutathione S-transferases, Esterases and NADH dehydrogenase increased compared to that found in the control of the same age group of nymphs and it was concluded that these enzymes might be involved in the metabolism of IBA. The other two enzymes, NADH oxidase and Glutathione reductase showed no significant increase in their activity compared to that in the control of the same age group. It was hypothesized that the latter enzymes do not play any significant role in the metabolism of IBA.  相似文献   
6.
The activity of catalase, glutathione peroxidase, superoxide dismutase, O-demethylase, ATPase and succinate dehydrogenase, belonging to two main classes of detoxification enzymes (i.e. hydrolases and oxido-reductases), mostly involved in metabolism and degradation of xenobiotics in insects, were assessed under the influence of kinetin, a plant growth regulator (PGR). The nymphs (48-52 hr old) of Lipaphis erysimi (Kalt.) were permitted to feed on radish plant, Raphanus sativus L. treated with kinetin (400 ppm) for 13, 25 and 37 hr. It was found that the activity of catalase, glutathione peroxidase and superoxide dismutase increased significantly when compared with the control of the same age group, which indicated that these enzymes might be playing a significant role in the metabolism of kinetin in this insect. The activity of O-demethylase showed an increase up to 25 hr of the treatment but it decreased under prolonged treatment whereas the activity of succinate dehydrogenase fluctuated insignificantly. ATPase showed a decrease in the activity with the treatment suggesting kinetin's interference in synthesis of ATPase.  相似文献   
7.
Overbank and stream sediments have been studied in the Community of Madrid. Four vertical profiles have been sampled corresponding to Guadarrama, Jarama, and finally Manzanares River, where two profiles have been studied upstream (El Pardo profile) and downstream (Rivas profile) Madrid city. Sieved samples (<63 µm) were subjected to total (ICP-MS/ICP-OES and INAA) and partial analysis (ICP-MS). AMS radiocarbon dating techniques revealed a young age (170 ± 40 years BP) at 2.40–2.65 m depth for Rivas profile. It has not been possible to detect pristine or pre-industrial overbank sediments, since in the rest of the studied profiles, anthropogenic wastes were found even in the lower levels. Three main sources of sediment have been detected in the area. Granitic and arkosic geology, located in the northern part of Madrid (U, Th, W, K, Na, or rare earth elements); clays located in the southeast of Madrid (Ni, Cr, or V), and finally an anthropogenic source has been identified (Au, Ag, Pb, Zn, or Sb) in Rivas profile. The influence of the anthropogenic activity has been established based on the contents distribution of contaminant elements in the profile. This can be associated to the growth of industrial activities and population in the city of Madrid during the last decades. The comparison of the profiles by a k-means cluster analysis showed some similarities for these samples that could have analogous sources (anthropogenic and geological).  相似文献   
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