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1.
Abstract

Wine and Arak, the national alcoholic drink in Lebanon, were prepared from grape juice fortified with fenitrothion to a concentration of 20ppm. Samples of the 11 fractions produced by the fermentation and distillation steps were analyzed for fenitrothion residues using gas chromatography (GC) and enzyme‐linked immunosorbent assay (ELISA). Results of residue analyses showed that the two techniques were highly correlated (r = 0.978) and indicated that fenitrothion was stable during the fermentation steps but not during distillation. The clarified wine 35 days later contained about 85% (15.3 ppm) of the fenitrothion concentration found in the juice as determined by GC analysis. Arak was prepared by a two‐steps distillation of the clarified wine. The alcohol distillate and undistilled fraction from the first distillation contained 2.5 ppm and 5.8 ppm of fenitrothion, respectively. No fenitrothion residues were detected by both techniques in the four fractions collected from the second distillation step.  相似文献   

2.
Wine and Arak, the national alcoholic drink in Lebanon, were prepared from grape juice fortified with fenitrothion to a concentration of 20ppm. Samples of the 11 fractions produced by the fermentation and distillation steps were analyzed for fenitrothion residues using gas chromatography (GC) and enzyme-linked immunosorbent assay (ELISA). Results of residue analyses showed that the two techniques were highly correlated (r = 0.978) and indicated that fenitrothion was stable during the fermentation steps but not during distillation. The clarified wine 35 days later contained about 85% (15.3 ppm) of the fenitrothion concentration found in the juice as determined by GC analysis. Arak was prepared by a two-steps distillation of the clarified wine. The alcohol distillate and undistilled fraction from the first distillation contained 2.5 ppm and 5.8 ppm of fenitrothion, respectively. No fenitrothion residues were detected by both techniques in the four fractions collected from the second distillation step.  相似文献   

3.
Abstract

14C‐p,p'‐DDT‐bound residues in soil can be released by treatment with concentrated sulphuric acid at ambient temperatures. Within 6 days, about 70% of the bound residues was released. Bound residues released after 9 months incubation with 14C‐DDT showed the presence of DDT and DDE only while bound residues released after 18 months, contained in addition 13% DDD.

Release of bound 14C‐residues also occurs readily following inoculation of the soil‐bound residues with fresh soil or with individual microorganisms. Almost complete release of bound residues was observed after incubation for 45 days. The rate of release was rapid during the first two weeks and decreased thereafter. TLC and HPLC analysis showed that the released residues contained DDE (about 80%) and a smaller amount of DDD. The disappearance of DDT from the released residues may be attributed to its microbiological degradation to DDE and DDD, shortly after its release.  相似文献   

4.
Abstract

Laboratory studies were conducted to investigate some of the factors influencing pesticide degradation in‐ aqueous systems. Parathion added to natural water in ethanol, acetone or without organic solvent, was completely degraded within 2 wk. While most of the parathion was reduced to amino‐parathion when added in ethanol, no amino‐parathion was detected in the presence of acetone or when no solvent was added, suggesting that in the latter two cases the insecticide was aerobically degraded to other metabolites. No paraoxon was detected. When ethanol concentration was increased from 1% to 2 and 4%, the rate of parathion degradation was inversely related to the ethanol concentration. In the presence of glucose as a carbon source, approximately 50% of the parathion was reduced to aminoparathion. DDT degradation in natural water was more rapid when it was added in ethanol than when added in acetone. The only DDT metabolite detected was TDE, with about 36% conversion in presence of ethanol, and 20% when the DDT was added in acetone.  相似文献   

5.
Abstract

14C‐DDT dissipated gradually from natural water under outdoor conditions and declined to 40% of the applied radioactivity after 5 months. The losses are due to adsorption to particulates and volatilization from the water surface. In natural water DDT undergoes gradual conversion to DDE as the major degradation product and to a lesser extent to DDD. It may be concluded that DDT dissipates and degrades fairly rapidly in subtropical natural waters. Adsorption to particulate matter contributes to partial “removal” of DDT.  相似文献   

6.
Abstract

In support of field data, laboratory studies were conducted on volatilization, mineralization and binding of 14C‐p,p'‐DDT in soils at Sao Paulo. Incubation of soil for 6 weeks did not result in volatilized organics or mineralization; with >95% extractable radiocarbon in the form of p,p'‐DDT. Small amounts of bound residues (1.8%) were detected in soil. These data confirm the very slow dissipation of DDT in the field which presumably relates to the acidic pH of soil (4.5–4.8).

Bound 14C‐residues in soils treated with 14C‐p,p'‐DDT at Praia Grande and Sao Paulo could be released (5–21%) by sulphuric acid treatment. The released residue had the composition: 69–90% DDT, 7–32% DDD and 0–3% DDE. Incubation of soil bound 14C‐residues with fresh inoculum for 3 months did not result in release of 14C.

Dissipation from wooden surfaces was fairly slow. After 20 weeks, 74% of the applied radioactivity could be recovered; 44% hexane‐non‐extractable.  相似文献   

7.
Abstract

Dissipation of 14C‐p,p'‐DDT from water was studied for 180 days under outdoor conditions. DDT dissipated rapidly with overall half‐life of 53 days. The main degradation products were p,p'‐DDE and p,p'‐DDD. A portion of 14C‐residues was found in the sediment plus biomass (pellet) and on the inner surface of the glass container. This amounted to 7.2 and 6.7% of the initially added radioactivity, respectively. After 6 months, bound14C was more as compared to extractable 14C and p,p'‐DDD was the major metabolite of p,p'‐DDT in the extractable fraction. DDT dissipated from clay plates under indoor conditions with an overall half‐life of 160 days.  相似文献   

8.
Fresh tomatoes were cut, fortified with 25 ppm (micrograms/g) of parathion (0,0-diethyl 0-4-nitrophenylphosphorothioate) and processed into either juice or ketchup. Tomato juice was canned, while ketchup was placed in bottles. All samples were stored at room temperature for analysis at two-monthly intervals. Parathion residues were measured quantitatively by GLC, while the two metabolites, aminoparathion (0,0-diethyl 0-4-aminophenylphosphorothioate) and 4-nitrophenol, were determined colorimetrically. The presence of the three compounds was confirmed qualitatively by TLC. Blanching of tomatoes resulted in about 50% reduction of parathion level. Pulping of fruits caused a further decrease in parathion residues in juice as a result of its sorption and concentration in the semi-solid pulp. About 85% of parathion added to tomatoes was lost during the processing steps. Storage of juice resulted in a gradual decrease in parathion levels, whereby only 1.7% of the original amount was detected after six months of storage. The compound was stable in ketchup for the first four months of storage but decreased thereafter to almost 7% of the original quantity added to fruits. Aminoparathion and 4-nitrophenol were detected in low levels.  相似文献   

9.
Abstract

This research is a case study on detection of pesticides in river water, sediment as well as fish samples from Tapi River, among the major rivers of Gujarat, India. To investigate the misuse, concentration level and occurrence patterns of persistent pesticides, samples were collected from the river. Chlorpyrifos, methyl parathion, hexachlorocyclohexane (HCH), dichloro diphenyl trichloroethane (DDT) and endosulfan were analyzed by gas chromatography technique with flame ionization detector (FID). Scanty reports are available, but after 1999, no such data are reported as some of these pesticides have been banned. Although these pesticides are still in use which we observed from the obtained results. In this river, the amount of endosulfan, chlorpyrifos, and methyl parathion was observed in surface water with concentrations of 37.56?µg/L, 0.86?µg/L and 0.43?µg/L, respectively. Endosulfan, DDT and methyl parathion detected in sediment were 38.38?ng/g, 0.65?ng/g and 0.77?ng/g, respectively. In fish samples, levels of endosulfan, chlorpyrifos, and methyl parathion detected were 101.28, 0.392, and 3.49?ng/g correspondingly. Results showed that highly toxic pesticides are still being used in the surrounding area, and there is an urgent need for enforcement of rules to control the production and application of such pesticides.  相似文献   

10.
The northern gannets (Sula bassanus) nesting on Bonaventure Island, Quebec, were studied from 1968 to 1984 in order to measure environmental contaminant levels and their relationship to productivity. Fresh eggs in 1969 contained a mean DDE level of 18.5 mg kg(-1) and had shells which were 17% thinner than pre-1947 samples. Unhatched eggs in 1969 had no outer calcified layer, a mean thickness 20% less than the pre-1947 mean, and mean DDE concentration of 30.6 mg kg(-1). Significantly higher levels of eight contaminants were measured in unhatched than in fresh eggs collected in 1969. DDE and shell thinning were also intercorrelated with nine other contaminants; these data strongly implicate toxic chemicals, particularly DDE, as the main cause for the low breeding success of Bonaventure gannets from 1966 to 1974. Extensive use of DDT to control forest insects around the Gulf of St Lawrence ceased in 1969. Use of DDT, dieldrin and PCBs was restricted in North America during the early 1970s. Residues of DDT, DDD, DDE, PCBs, dieldrin, HCB and chlordane-related compounds in gannet eggs decreased significantly during this study. Heptachlor epoxide remained constant while alpha-HCH appeared to increase. Estimated half-lives ranged from 3.1 years for DDD to 35.4 years for oxychlordane. The breeding success and population of the colony have coincidentally increased.  相似文献   

11.
Abstract

The growth and total carbohydrate contents of Nostoc muscorum and Tolypothrix tenuis were greatly and significantly reduced by the application of parathion. “Chlorophyll a”, carotene biosynthesis and the rate of glucose absorption were enhanced after supplementation of parathion to the culture media of both cyanobacteria. Nitrogen released to the media, total nitrogen content and total nitrogen fixed were increased in both organisms‐ Increase in protein content was accompanied by remarkable drop in amino, peptide and ammonia fractions‐ Phosphorus uptake, RNA, DNA and total phosphorus content were accelerated to reach maximum accumulation at the highest insecticide level. In metabolism study using 14C‐labelled compound, parathion was readily degraded by Nostoc and Tolypothrix. Following ten days incubation, the aqueous fractions contained 21.1% and 18.1% of the initial activity in Nostoc and Tolypothrix respectively. TLC analysis of the hydrolytic products revealed the presence of three metabolites: p‐aminophenol, p‐nitrophenol and aminoparathion.  相似文献   

12.
Abstract

Laboratory experiments were conducted to determine the effect of DDT, fauna and flooding on microbial growth in a sandy loam. Results indicated that soil microorganisms can tolerate the presence of DDT. Earthworms singly or in combination with springtails affected the average population of fungi in the DDT‐untreated samples and of aerobic bacteria in the DDT‐treated soils. Soil animals did not appear to have any effect on the populations of anaerobic bacteria. However, waterlogging brought about a decrease in aerobic bacteria and fungal populations, and an increase in anaerobic bacteria in both soils.  相似文献   

13.
Xin J  Liu X  Liu W  Jiang L  Wang J  Niu J 《Chemosphere》2011,84(3):342-347
This study provides the first intensive investigation of Dichlorodiphenyltrichloroethanes (DDT) distribution in typical paint factories and shipyards in China where DDT containing antifouling paint were mass produced and used respectively. DDTs were analyzed in soil, sludge and sediment samples collected from three major paint factories and two shipyards. The results showed that the total DDTs concentrations detected in paint factory and shipyard sites ranged from 0.06 to 8387.24 mg kg−1. In comparison with paint factory sites, the shipyard sites were much more seriously contaminated. However, for both kinds of sites, the DDTs level was found to be largely affected by history and capacity of production and use of DDT containing antifouling paint. (DDE + DDD)/DDT ratios indicated that DDT containing antifouling paint could serve as important fresh input sources for DDTs. It can be seen that most samples in shipyards were in ranges where heavy contamination and potential ecological risk were identified.  相似文献   

14.
Abstract

The effects of temperatures and solar radiation on the dissipation of 14C‐p,p'‐DDT from a loam soil was studied by quantifying volatilization, mineralization and binding. The major DDT loss occurred by volatilization, which was 1.8 times more at 45oC than at ambient temperature (30°C). Mineralization of DDT slowly increased with time but it decreased slightly with increase in temperature. Binding of DDT to soil was found to be less at higher temperatures (35 and 45°C) as compared to ambient temperature. Degradation of DDT to DDE was faster at higher temperatures.

Exposure of non‐sterilized and sterilized soils treated with 14C‐DDT to sunlight in quartz and dark tubes for 6 weeks resulted in significant losses. Volatilization and mineralization in quartz tubes were more as compared to dark tubes. The volatilized organics from the quartz tubes contained larger amounts of p,p'‐DDE than the dark tubes. Further, higher rates of volatilization were found in non‐sterilized soils than in sterilized soils. The results suggest that faster dissipation of DDT from soil under local conditions relates predominantly to increased volatilization as influenced by high temperature and intense solar radiation.  相似文献   

15.
Abstract

Organochlorine pesticide and herbicide levels were monitored in samples of a variety of edible finfish harvested from the Maryland section of the Chesapeake Bay and its tributaries over a five‐year period (1976–80). Qualitative and quantitative information was obtained for the various polychlorinated biphenyls (PCB's), heptachlor, α‐BHC, chlordane, DDD, DDE, DDT, dieldrin, endrin, heptachlor‐epoxide, lindane, mirex, methoxychlor, aldrin, toxaphene, hexachlorobenzene, kepone and dacthal.

In addition to analyses of the flesh of the animals, organochlorine residue levels were determined in roe or gonad tissue of several samples. Striped bass, white perch and yellow perch samples showed significantly higher concentrations of certain of these substances in roe or gonad tissue, especially PCB's, chlordane, DDD and dieldrin. Significantly higher levels of six organochlorine residues were found in the gonad tissue of striped bass; however, similar studies on gonad tissue of American Shad, harvested from the same region, show no such enhancement. Rather, the reverse is true; levels of certain organochlorine residues are higher in flesh tissue.

All mean values, and virtually all individual values of organochlorine concentrations in the edible portion of the fish were within the U.S. Food and Drug Administration guideline, where such guidelines have been established.  相似文献   

16.
ABSTRACT

The aim of this study was to determine the level of chlorinated hydrocarbon residues in selected edible mushrooms from north-eastern Poland. The experiment was carried out on 45 samples consisting of 15 fruiting bodies each of the following species: Boletus edulis, Imleria badia and Cantharellus cibarius. Dried samples were subjected to extraction of lipids with a Soxhlet and a standard procedure—based on the decomposition of lipids by concentrated sulfuric acid and the release of organic insecticides to the hexane layer—was used to determine chlorinated hydrocarbons. The quantitative determination of DDT, DDE, DDD and γ-HCH were conducted using gas chromatography with electron capture detection (GC-ECD). Chlorinated hydrocarbons were found in all tested samples. The contents of these compounds varied between all three species. Mean content of γ-HCH in B. edulis, I. badia and C. cibarius was: 2.60; 4.83; 7.52 µg kg?1 of lipids, while the content of ΣDDT was: 57.02; 25.20; 127.10 µg kg?1 of lipids, respectively. These results show that mushrooms from the north-eastern part of Poland can be used as potential bio-indicators of environmental contamination with chlorinated hydrocarbons. Moreover, the studied fungi could still be used as food due to the low levels of analyzed organochlorine compounds.  相似文献   

17.
The transformation of DDT was studied in an anaerobic system of dissimilatory iron-reducing bacteria (Shewanella decolorationis S12) and iron oxide (α-FeOOH). The results showed that S. decolorationis could reduce DDT into DDD, and DDT transformation rate was accelerated by the presence of α-FeOOH. DDD was observed as the primary transformation product, which was demonstrated to be transformed in the abiotic system of Fe2+ + α-FeOOH and the system of DIRB + α-FeOOH. The intermediates of DDMS and DBP were detected after 9 months, likely suggesting that reductive dechlorination was the main dechlorination pathway of DDT in the iron-reducing system. The enhanced reductive dechlorination of DDT was mainly due to biogenic Fe(II) sorbed on the surface of α-FeOOH, which can serve as a mediator for the transformation of DDT. This study demonstrated the important role of DIRB and iron oxide on DDT and DDD transformation under anaerobic iron-reducing environments.  相似文献   

18.
Abstract

Effect of acute doses of technical grade of dichloro diphenyl trichloro ethane (DDT) and piperonyl butoxide (PB) on hepatic micro‐somal cytochrome P450 (Cyt. P450) and cytosolic glutathione‐S‐transferase (GST) activity in pigeon were studied after 24 hours of treatment. A completely reverse trend of changes in Cyt. P450 and GST activity were found as increase in Cyt. ?450 paralleled with decrease in GST activity following exposure to DDT. However, intensity of changes in Cyt. P450 was greater than that of GST. A dose dependent decrease in Cyt. ?450 and GST activity was observed after PB treatment. The study may, therefore, throw some light on metabolic alterations in wild birds resulting from environmental pollution by DDT and allied chemicals.  相似文献   

19.
Abstract

Genotoxicity of the insecticide methyl parathion was investigated in Salmonella typhimurium and Escherichia coli bacterial test systems for the detection of back mutations and DNA‐damage. Methyl parathion was mutagenic to S. typhimurium strain TA100 after activation with rat liver microsomal and cytosolic enzymes. In DNA repair tests, methyl parathion was effective in inducing damage to the S. typhimurium strain TA1538 which lack excision repair compared to the strain TA1978 which is proficient in excision repair mechanisms. Normal laboratory light conditions had no effect on the mutagenicity tests, however, exposure of methyl parathion in the petri dish containing the tester strain TA100 and rat liver microsomal and cytosolic enzymes reduced the mutagenic activity and increased the toxic effects of methyl parathion.  相似文献   

20.
"Semellon" grape juice fortified with a high level of 25 ppm parathion was fermented using Saccharomyces cerevisiae var. ellipsoideus. After 12 days inte parathion levels in the wine and lees were 10.3 and 156 ppm, respectively; the paraoxon, aminoparathion, and p-nitrophenol levels in the wine were 0.16, 0.20, and 4.5 ppm, respectively, and in the lees were 0.04, 3.1 and 10 ppm, respectively. Thus, hydrolysis of parathion to p-nitrophenol and parathion sorption to sedimented particulate matter were important pathways for parathion residue reduction in the wine. The 56-day-old finished wine just prior to bottling contained 8.8 ppm parathion, 0.04 ppm paraoxon, 0.21 ppm aminoparathion, and 3.0 ppm p-nitrophenol. Two months storage at 24 degrees, 12 degrees, 4 degrees, and -20 degrees C had no effect on paraoxon and aminoparathion residue levels in the wine; parathion residues in wine decreased at all storage temperatures.  相似文献   

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