有机磷农药降解方法及应用研究新进展

现代农业的发展和有机磷农药的使用密切相关,所造成的严重的农产品和环境污染是农业发展有待解决的关键问题之一。介绍了超声波技术、吸附、洗涤和辐照等物理方法,微生物、降解酶和工程菌等生物方法,水解、氧化分解和光化学降解等化学方法对有机磷农药的降解作用及其相关的应用研究。     

戊唑醇残留分析方法实验室内质量控制研究

文章确立了小麦、香蕉中戊唑醇残留检测方法,小麦样品加水10 mL用丙酮为萃取溶剂,石油醚液液分配,中性氧化铝柱层析净化,用气相色谱(GC-NPD)检测。香蕉样品加水5 mL用丙酮为萃取溶剂,石油醚液液分配,浓缩后用气相色谱(GC-NPD)检测。分别设置不同时间批次,同一批次间的平行样及实验室内人员分析,分别从方法灵敏度、方法准确度、方法精密度及其质量控制图、标准工作液的稳定性来探讨该方法的可靠性,结果表明该方法可以作为香蕉和小麦种戊唑醇残留检测的标准分析方法。     

岩溶地下河系统中有机氯的分布特征与来源分析

选取重庆老龙洞、青木关岩溶地下河为研究对象,采用气相色谱仪-微池电子捕获检测器(GC-μECD)分析两条地下河水体中21种有机氯农药(OCPs)的浓度.结果表明,南山地下河中六六六(HCHs)和艾氏剂类化合物(ALDs)是主要检出物,青木关地下河中HCHs和甲氧滴滴涕是主要检出物.南山、青木关地下河中均未检出o,p'-DDE、p,p'-DDE、o,p'-DDD,同时,青木关地下河还未检出o,p'-DDT、狄氏剂,其余OCPs在两条地下河中检出率高达100%.青木关地下河中OCPs浓度范围为145~278 ng·L-1之间,平均值为213 ng·L-1;南山老龙洞地下河中OCPs浓度介于17.7~40.8 ng·L-1之间,平均值为32.7ng·L-1.两条地下河中各OCPs组分表现为地下河出口大于入口.通过对OCPs污染来源分析,发现两地下河流域滴滴涕(DDTs)主要来自于历史上工业DDTs输入,氯丹主要来自于大气沉降.六六六(HCHs)主要来源是林丹的输入,南山地下河属于历史污染,青木关地下河上游的甘家槽有新的HCHs输入.与国内外其他各水体相比,南山地下河水体中HCHs、DDTs浓度处于低水平;青木关下河处于中等偏高水平.结合中外用水卫生标准,发现南山地下河和青木关地下河未超过饮水安全标准.青木关应禁止农田施用有机氯农药,保护地下河生态环境.     

Biostability in distribution systems in one city in southern China：Characteristics, modeling and control strategy

This study investigated the bacterial regrowth in drinking water distribution systems receiving finished water from an advanced drinking water treatment plant in one city in southem China. Thirteen nodes in two water supply zones with different aged pipelines were selected to monitor water temperature, dissolved oxygen （DO）, chloramine residual, assimilable organic carbon （AOC）, and heterotrophic plate counts （HPC）. Regression and principal component analyses indicated that HPC had a strong correlation with chloramine residual. Based on Chick-Watson＇s Law and the Monod equation, biostability curves under different conditions were developed to achieve the goal of HPC 100 CFU/mL. The biostability curves could interpret the scenario under various AOC concentrations and predict the required chloramine residual concentration under the condition of high AOC level. The simulation was also carded out to predict the scenario with a stricter HPC goal （≤50 CFU/mL） and determine the required chloramine residual. The biological regrowth control strategy was assessed using biostability curve analysis. The results indicated that maintaining high chloramine residual concentration was the most practical way to achieve the goal of HPC ≤ 100 CFU/mL. Biostability curves could be a very useful tool for biostability control in distribution systems. This work could provide some new insights towards biostability control in real distribution systems.     

Mutagenic and cytotoxic potential of Endosulfan and Lambda-cyhalothrin - In vitro study describing individual and combined effects of pesticides

Excessive use of pesticides poses increased risks to non target species including humans. In the developing countries, lack of proper awareness about the toxic potential of pesticides makes the farmer more vulnerable to pesticide linked toxicities, which could lead to diverse pathological conditions. The toxic potential of a pesticide could be determined by their ability to induce genetic mutations and cytotoxicity. Hence, determination of genetic mutation and cytotoxicity of each pesticide is unavoidable to legislate health and safety appraisal about pesticides. The objective of current investigation was to determine the genotoxic and cytotoxic potential of Endosulfan（EN） and Lambda-cyhalothrin（LC）; individually and in combination. 3-（4,5-Dimethylthiazol-2-yl）-2,5-Diphenyltetrazolium Bromide（MTT） assay was utilized to determine cytotoxicity, while two mutant histidine dependent Salmonella strains（TA98, TA100） were used to determine the mutagenicity of EN and LC.Moreover, mutagenicity assay was conducted with and without S9 to evaluate the effects of metabolic activation on mutagenicity. Even though a dose dependent increase in the number of revertant colonies was detected with EN against both bacterial strains, a highly significant（p 〈 0.05） increase in the mutagenicity was detected in TA98 with S9. In comparison, data obtained from LC revealed less mutagenic potential than EN. Surprisingly,the non-mutagenic individual-concentrations of EN and LC showed dose dependent mutagenicity when combined. Combination of EN and LC synergistically induced mutagenicity both in TA98 and TA100. MTT assay spotlighted comparable dose dependent cytotoxicity effects of both pesticides. Interestingly, the combination of EN and LC produced increased reversion and cytotoxicity at lower doses as compared to each pesticide, concluding that pesticide exposure even at sub-lethal doses can produce cytotoxicity and genetic mutations, which could lead to carcinogenicity.     

溴氰虫酰胺及其代谢物在土壤和葱中残留行为

论文建立了溴氰虫酰胺及其代谢产物J9Z38在土壤和葱中残留量的高效液相色谱三重四级杆串联质谱(LC-MS/MS)测定方法,其最小检出量分别为0.1×10-9g和0.5×10-9g;溴氰虫酰胺和J9Z38在葱和土壤样品中最低检出浓度均为0.01 mg/kg。在0.01~0.1mg/kg添加水平下,溴氰虫酰胺在土壤和葱中添加回收率分别为87.8%~99.3%和79.6%~100.3%,相对标准偏差分别为1.6%~4.6%和5.1%~7.2%;J9Z38在土壤和葱中添加回收率分别为76.0%~100.8%和77.8%~98.9%,相对标准偏差分别为5.6%~10.0%和4.2%~8.3%,均符合农药残留量分析的要求。同时,为了解100 g/L溴氰虫酰胺油悬剂在葱上施用后,溴氰虫酰胺在土壤和葱中的残留消解动态及最终残留状况,在北京和山东两地开展了大田试验研究。结果表明,溴氰虫酰胺在土壤和葱中的残留消解半衰期分别为1.3~2.6 d和2.4~4.3 d,属于易降解农药。100 g/L溴氰虫酰胺油悬剂按推荐剂量和1.5倍推荐剂量在葱中各施药3次和4次,距最后一次施药1 d时,溴氰虫酰胺在葱中最高残留量为0.13 mg/kg,表明100 g/L溴氰虫酰胺油悬剂在葱中使用后,溴氰虫酰胺在葱中的残留量较低。     

液液萃取-气相色谱法测定地表水中17种有机氯农药研究

建立了二氯甲烷液液萃取-气相色谱法同时测定地表水中17种有机氯农药的方法。标准曲线线性良好,17种化合物的相关系数R2均大于0.999。当取样量为200 mL时,方法检出限在0.015μg/L~0.062μg/L之间。以超纯水样品进行基质加标实验,重复测定6次的相对标准偏差为1.2%~6.2%,平均加标回收率为72.8%~93.5%。方法简单快捷,精密度良好,准确性高,适用于地表水中痕量有机氯农药的测定。     

气相色谱在果蔬农药残留检测中的应用进展

结合农药残留分析的重要性,文章主要综述了目前农药残留检测的常用分析方法——气相色谱法(GC)、气相色谱-质谱法(GC-MS)以及气相色谱-光谱法,并展望今后农药残留技术的发展方向。     

有机磷农药降解酶的研究进展

有机磷农药的不合理使用造成农药残留严重超标,对环境的污染及危害也日益严重,因此,有机磷农药降解方法的研究成为了当今的热点之一。本文综述了有机磷降解酶的发展及其基因工程的研究情况,对降解酶的应用现状进行了简要介绍,最后指出了有机磷降解酶技术未来的研究方向。     

浅谈黑龙江及乌苏里江流域废水中污染物排放特征

以跨界流域黑龙江和乌苏里江为研究对象,通过合理的流域断面设置,对流域废水中的污染物及农药残留进行分析测定,通过监测结果为以后的污染防治提供依据。