首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Summary Chlorinated insecticidesviz p,p-DDT, aldrin, endrin and lindane stimulated the synthesis of arginine+histidine, leucine, lysine, proline, and tyrosine in maize but decreased the content of tryptophan. However, synthesis of methionine was stimulated by the application of aldrin, endrin, and lindane only. On the otherhand, synthesis of valine was inhibited by aldrin, endrin and DDT only.  相似文献   

2.
Cyprinus carpio (Linnaeus, 1758) caught in Sidi Salem Dam in 2011 were analysed for the levels of organochlorine pesticides (OCPs), including hexachlorobenzene (HCB), aldrin, heptachlor, lindane, dieldrin, endrin, and pp-DDT and its two main metabolites pp-DDD and pp-DDE, in order to evaluate the extent of contamination of the dam. Fish were sampled monthly within the dam during 2011. Muscle, liver and gill tissues were analysed by gas chromatography for the determination of OCPs. Samples had variable concentrations of OCPs, ranging from 2.26 to 17.93 ng g?1, 0.59 to 42.67 ng g?1 and 3.30 to 84.27 ng g?1, which were isolated from gills, muscle and liver, respectively. The organochlorine pesticide levels found posed no threat to human health. The highest OCP levels were found in the liver tissues. The pp-DDE concentrations and their ratios to ΣDDTs indicate aged DDT pollution and suggests that there has been no recent input of technical DDT from the agricultural areas into Sidi Salem Dam.  相似文献   

3.
Samples of water, sediments and aquatic weeds were collected from 26 sites in the Nyando River catchment of the Lake Victoria basin in 2005–2006. The objective was to investigate levels of organochlorine pesticides that have either been banned or are restricted for use in Kenya. The pesticides investigated were lindane, aldrin, endosulfan, endrin, dieldrin, DDT, heptachlor and methoxychlor. These pesticides had previously found wide applications in public health and agriculture in Kenya for control of disease vectors and crop pests respectively. Results showed that mean concentrations were highest for methoxychlor (8.817 ± 0.020?µg l?1) in water, sediments (92.893 ± 3.039 µg kg?1), and weeds (39.641 ± 3.045?µg kg?1), the weeds also tended to accumulate aldrin (15.519 ± 3.756?µg kg?1). The results show that the pesticides are still in use and are detected in the catchment. Stringent management and public awareness measures are required to enforce the ban on the organochlorine pesticides in order to safeguard the environment and ecosystems of Lake Victoria.  相似文献   

4.
RBC counts, Ht value and Hb content in both species exposed to DDT and endrin concentrations were not significantly different from those of controls. WBC counts in both species exposed to the two pesticides for 96 hr decreased significantly at different concentrations. The variance ratios of cations and anions were consistently more concentrated in the serum of DDT- and endrin-exposed fishes. Serum cholesterol was sharply elevated in all the lots exposed to pesticides. Exposure to sublethal concentrations of DDT and endrin impaired liver function, as evidenced by the transfer of major cations from hepatic tissue to the serum and by elevated serum cholesterol.  相似文献   

5.
Residues of chlorinated hydrocarbon insectidies and some of their metabolites, including p,p'-DDT, p,p'-DDD, p,p'-DDE, gamma-BHC, aldrin, dieldrin, heptachlor and heptachlor epoxide, were examined in the soils collected from 21 tea-gardens distributed in 15 countries of 6 prefectures in 1977, and from 100 locations distributed in 46 counties of 10 prefectures in 1984 in Taiwan. Although the use of these chlorinated hydrocarbon insecticides has been banned for many years, minor amounts of residues in the soils have still been detected. From 1977 to 1984, average residues of the chlorinated hydrocarbon insecticides and their metabolites in the soils of tea-gardens decreased from 5.64 to 0.06 ppb for gamma-BHC, 97 54 to 1.10 ppb for aldrin, 35.91 to 1.00 ppb for p,p'-DDE, 17.41 to 0.28 ppb for dieldrin, and 30.17 to 3.42 ppb for p,p'-DDT. But the number of positive cases increased for all chlorinated hydrocarbon insecticides tested, the residual levels were not significantly different among soils with different physiochemical properties or among soil layers. No significant amount of these insecticides was found in the processed tea.  相似文献   

6.
Using a continuous exposure technique, the toxicity of 35 compounds to the bulb mite, Rhizoglyphus echinopus (Fumouze and Robin) was examined after 48 h. Sixteen acaricides yielded an LC50 of <1.0 mg cm2. The highest toxicity was exhibited by cyclodiene GABA antagonists (dieldrin, endrin and aldrin), some organophosphate (chlorpyrifos, diazinon and azinphosethyl) and carbamate (carbofuran) anticholinesterases and a thiazolidine flubenzimine. Oxythioquinox, fenazaflor, fenazaquin and amitraz were less toxic than the cyclodienes, organophosphates and carbamates. The sodium channel agonists (DDT and pyrethroids) and several specific acaricides with other modes of action were inactive (LC50 >11.0 mg cm-2).  相似文献   

7.
Several insecticides have been used as protectants against lettuce root aphid, including, in 1955, lindane, schradan, aldrin and endrin; the last-named giving the most promising results. With a dressing of an equal weight of 50% endrin dust added to lettuce seed, 86% reduction in aphid numbers was obtained. In 1957, a seed dressing with endrin also gave a good control, which was superior to that obtained with thimet 44D. However, in 1956 and 1958 endrin seed dressing failed to control the aphid. When a seed dressing with endrin was supplemented by an endrin spray applied to the seedlings a consistently good control resulted.
A high level of aphid control was obtained in 1958 with two sprays of diazinon applied along the lettuce rows, the first applied after singling and the other at the early rosette stage. Diazinon or endrin, applied to the soil at 4 lb. actual insecticide/acre and rotavated into the top 3 in. before sowing, also gave high levels of control.
No recommendations for the use of endrin on lettuce can be made until levels and persistence of residues are known.  相似文献   

8.
Organochlorine pesticides (OCPs) used in agriculture and for public health purposes were banned in Thailand over the past decade; however, their persistent residues have been found in several agricultural areas of the country. This may result in adverse effects to human populations. This study investigated the concentration of organochlorine pesticides residues (OCPRs) in surface water and evaluated the potential cancer risk associated with dermal contact of the local fisherman fishing in the Khlong 7 canal, Rangsit agricultural area, central Thailand. Water samples were extracted using liquid-liquid extraction (LLE) and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb or ng/ml) levels, that is, ∑ Endosulfan (α -, β -, and -sulfate) 0.082 ng/ml > DDT and derivatives 0.019 ng/ml > ∑ HCH (α -, γ -, β -, and δ -HCH) 0.014 ng/ml > aldrin and dieldrin 0.007 ng/ml > heptachlor and heptachlor epoxide 0.0068 ng/ml > endrin and endrin aldehyde 0.005 ng/ml > methoxychlor 0.001 ng/ml, respectively. Using the worst-case scenario defined as the reasonable maximum exposure (RME) to assess the potential cancer risk, five OCPs (dieldrin, 4,4′ -DDT, β -HCH, heptachlor, and heptachlor epoxide) may pose a risk of concern on a lifetime human carcinogenesis greater than one in a million.  相似文献   

9.
Determination of DDT and endrin concentrations was carried out in fishes of Nozha hydrodrome to elucidate reasons for variations in the values, since little seems to be known about pesticide residues in Egyptian freshwater fishes. This study documents and examines the accumulation and biotransformation of water-borne pesticides by the gills, liver, gonads, muscle and heart of fishes tested. The response of eel and mullet to concentrations of 0.05, 0.1, 0.5 and 1.0 ppb DDT and endrin varied among organs, the residues were highest in the liver, intermediate in the gonads and low to non-detectable in muscles and heart for both species.  相似文献   

10.
Like most of Madagascar's endemic primates, ring‐tailed lemurs (Lemur catta) face a number of threats to their survival. Although habitat loss is of greatest concern, other anthropogenic factors including environmental contamination may also affect lemur health and survival. In this study, we examined ring‐tailed lemurs from the Beza Mahafaly Special Reserve (BMSR), southern Madagascar for exposure to organochlorine (OC) pesticides and metals and examined differences in contaminant concentrations between sexes and among age groups, troops, and habitats. A total of 14 pesticides and 13 metals was detected in lemur blood (24 individuals) and hair (65 individuals) samples, respectively. p,p′‐DDT, heptachlor, aldrin, heptachlor epoxide, endrin aldehyde, and endrin were among the most prevalent pesticides detected. Surprisingly, the persistent metabolite of p,p′‐DDT, p,p′‐DDE, was not detected. The most commonly detected metals were aluminum, zinc, boron, phosphorus, silicon, and copper, whereas metals considered more hazardous to wildlife (e.g. arsenic, cadmium, lead, selenium, vanadium) were not found above detection limits. Overall, concentrations of OC pesticides and metals were low and similar to those considered to be background concentrations in other studies examining the ecotoxicology of wild mammals. Few inter‐sex, ‐age, ‐troop, and ‐habitat differences in contaminant concentrations were observed, suggesting a uniform distribution of contaminants within the reserve. Several statistically significant relationships between lemur body size and contaminant concentrations were observed, but owing to the lack of supportive data regarding contaminant exposure in wild primates, the biological significance of these findings remains uncertain. Results of this study document exposure of ring‐tailed lemurs at BMSR to multiple OC pesticides and metals and provide essential baseline data for future health and toxicological evaluations of lemurs and other wild primates, especially those in regions with expanding agricultural and mining operations. Am. J. Primatol. 71:998–1010, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

11.
This report describes the selective isolation of dieldrin- and endrin-degrading bacteria from soil with high degradation activity toward dieldrin and endrin. Several enrichment cultures from the soil were arranged with several structural analogs of dieldrin and endrin as a growth substrate and examined for their degradation activities toward dieldrin and endrin. An enrichment culture with 1,2-epoxycyclohexane (ECH) was found to aerobically degrade dieldrin and endrin. Denaturing gradient gel electrophoresis (DGGE) indicated that three types of bacteria were predominant in the ECH enrichment culture. Of the three major bacteria, two isolates, Burkholderia sp. strain MED-7 and Cupriavidus sp. strain MED-5, showed high degradation activity toward dieldrin and endrin. The degradation efficiencies of strain MED-7 and MED-5 were 49% and 38% toward dieldrin, respectively, and 51% and 40% toward endrin, respectively, in the presence of ECH for 14 days. These results indicated that ECH was a useful substrate for selective and efficient isolation of dieldrin- and endrin-degrading bacteria from soil containing numerous bacteria. Interestingly, the two isolates could also degrade dieldrin and endrin even in the absence of ECH. These are the first microorganisms demonstrated to grow on dieldrin and endrin as the sole carbon and energy source under aerobic conditions.  相似文献   

12.
Chlordane, aldrin and dieldrin act on the bipolar neurones and the repolarization of the photoreceptors. Only aldrin and dieldrin disturb photoreceptor excitability. Taking account of experimental results previously obtained with DDT and HCH, a relation between chemical structure and retinian toxicity has been proved.  相似文献   

13.
Endrin is persistent organic pollutants that contaminate soil in many parts of the world. In this study, endrin was used as the substrate for a degradation experiment with the white rot fungi of the genus Phlebia. The results of tolerance test showed that the tolerance level of Phlebia acanthocystis and Phlebia brevispora to endrin was higher than that of other fungi, and the tolerance coefficient of both strains to 1.0 mg/L endrin exceeded 0.9 in solid PDA medium. P. acanthocystis and P. brevispora could degrade endrin efficiently in pure culture, especially P. acanthocystis had the highest degradability of more than 80% after 20 d incubation. Compared with low-nitrogen medium, PDB medium is more suitable for the biodegradability of two fungi. Several hydroxylated products such as 8-hydroxyendrin and two monohydroxyendrin were detected, indicating that endrin was initially branched to different monohydroxylated products in fungal degradation. Moreover, a carboxylic acid product was obtained from P. acanthocystis culture, suggesting that the carboxylation reaction occurred in bioconversion of endrin. The fungal cytochrome P450 enzymes play significant role in the in the initial hydroxylation process on endrin degradation. This is the first report that endrin is converted to hydroxylated and carboxylated metabolites by microorganisms.  相似文献   

14.
从长期受六六六污染的土壤中获得高效降解六六六的富集液 ,其对六六六 4种异构体的降解效果均为10 0 % ,但至今未能获得纯培养。根据国外报道的六六六脱氯基因linA序列 ,设计并合成一对引物 ,通过PCR技术从富集液总DNA中扩增了 4 71bp的基因片段 ,命名为linN ,测序结果表明linN与报道的脱氯基因linA和linA2的同源性达 99% ,与linA1的同源性达 97%。将linN定向克隆到pET 2 9α表达载体中 ,转化至E .coliBL2 1,经IPTG诱导后可表达分子量约 17kD的蛋白 ,表达产物占菌体总蛋白的 30 %左右 ;诱导后转化子的降解能力明显提高 ,粗酶也有很好的降解效果 ,为进一步分离纯培养和构建多功能农药残留降解菌提供了基础  相似文献   

15.
16.
This work describes the potential applicability of chemically and thermally treated date stones for removing drin pesticides (aldrin, dieldrin and endrin) from aqueous solutions. The effect of several parameters, such as sorbent particle size, adsorbent dose, shaking speed, shaking time, concentration of pesticide solution and temperature, was evaluated by batch experiments. Pesticide determination was carried out using stir bar sorptive extraction and gas chromatography coupled with mass spectroscopy. Maximum removal efficiency (93%) was reached using 0.1 g of acid-treated date stones (ATDS) (63–100 μm) and 100 mL of aldrin (0.5 mg L−1). The removal efficiency of drin pesticides decreased in the order of aldrin, dieldrin and endrin, and decreased as the temperature rose. Adsorption data were processed according to various kinetic models. Lagergren and Morris-Weber equations were applied to fit the kinetic results. The second order model was the most suitable on the whole, and intra-particle diffusion was found to be the rate-controlling the adsorption process. According to adsorption kinetic data, 3.5 h were considered as the equilibrium time for determining adsorption isotherms. Adsorption data were analyzed by the Langmuir, Freundlich and Dubinin–Radushkevich adsorption approaches. Experimental results showed that the Freundlich isotherm model best described the adsorption process. In addition, thermodynamic parameters such as ΔH, ΔS and ΔG were calculated. Negative values of ΔH and ΔG indicate the exothermic and spontaneous nature of pesticide adsorption on ATDS.  相似文献   

17.
Heme compounds, in combination with a reducing agent and oxygen, can express various activities of cytochrome P-450 enzymes. In the present study it was found that a mixture of hemin and excess cysteine was able to degrade the insecticide DDT partially. The major products were three water-soluble, non-toxic conjugates of DDT metabolites with cysteine which had lost two or three of the five chlorine atoms of DDT per molecule and whose structures were elucidated by gas chromatography/mass spectrometry. In 0.05 M NH4HCO3, pH 7.7/ethanol (5:6, by vol.), the degradation reaction catalyzed by the hemin-cysteine model system was at least 8 x 10(4) times faster than the uncatalyzed reaction. In the presence of a designed 24-residues polypeptide or beta-casein, two DDT-binding proteins, an additional fourfold increase in the rate of DDT degradation was observed. Although the concentrations of DDT and cysteine occurring in an organism would be expected to be lower than those in the experiments described, the formation of water-soluble conjugates of DDT metabolites with cysteine (and other amino acids) could also play a role in metabolism and excretion of DDT in vivo.  相似文献   

18.
The systematic identification and determination of many kinds of pesticides were tried by a combination of column, thin-layer and gas chromatography. Pesticides in the first division,1) e.g., aldrin, DMC ethylene, CPAS, DDDS, o,p′-DDT, p,p′-DDT, heptachlor, quintozene, Telodrin and tetrasul, were separated from pesticides in the second division,1) e.g., α-BHC, β-BHC, γ-BHC, trifluralin, CPA, CNP, nitrofen, endrin, dieldrin, dicofol, etc. by column chromatography. Further, pesticides in the first division were separated from each other and determined approximately by thin-layer and gas chromatography.

The recoveries of these pesticides, except for aldrin and CPAS, were about 100%. The recoveries of aldrin and CPAS were about 70 %, due to decomposition during the procedures, or to adsorption on the adsorbent during the column chromatography. It was presumed from GC-MS data that CPAS was decomposed to DDDS, tetrasul and other compounds during the procedures.  相似文献   

19.
Ninety-three wild-type isolates identified as actinomycetes were tested against 11 organochlorine pesticides (OPs): aldrin, chlordane, DDD, DDE, DDT, dieldrin, heptachlor, and heptachlor epoxides, lindane, and methoxychlor. Qualitative screening agar assays displayed 62-78% tolerance of strains to OPs. Four strains designed M4, M7, M9 and M15 were selected based on multi-OP-tolerance, and identified as members of the streptomycetes group. Different growth profiles were observed in cultures of the four selected streptomycetes cultured in synthetic medium containing 5-50 microg x l(-1) aldrin or chlordane or lindane. Increase of aldrin removal by the selected microorganisms was concomitant with the 4.8-36.0 microg x l(-1) pesticide concentration range. After 72 h of streptomycete M7 growth in synthetic medium containing 48.0 microg x l(-1) aldrin, the remaining OP concentration in the supernatant was approximately 10% of the initial concentration. Also, in stationary growth phase less than 2.5 microg x l(-1) aldrin residual concentration was detected in the medium.  相似文献   

20.
Basic studies and applications on bioremediation of DDT: A review   总被引:2,自引:0,他引:2  
The persistent insecticide DDT (1,1,1-trichloro-2,2-bis (4-chlorophenyl) ethane) has been widely used for pest control in the management of mosquito-borne malaria and is still used for that purpose in some tropical countries. Considering the potential for negative effects due to DDT contamination, it is necessary to determine effective methods of remediation. Several methods have been used to degrade or transform DDT into less toxic compounds. Bacteria and white-rot fungi (WRF) have been shown to enhance the degradation process in soil using both pure and mixed cultures. Recently, a biological approach has been used as an environmentally-friendly treatment, using new biological sources to degrade DDT, e.g. brown-rot fungi (BRF), cattle manure compost (CMC) and spent mushroom waste (SMW). In this review, the abilities of BRF, CMC and SMW to degrade DDT are discussed, including the mechanisms and degradation pathways. Furthermore, application of these sources to contaminated soil is also described. The review discusses which is the best source for bioremediation of DDT.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号