5种杀虫剂对3种淡水浮游动物的急性毒性

探讨了5种不同类型杀虫剂(毒死蜱(Chlorpyrifos)、三氟氯氰菊酯(Cyhalothrin)、丁硫克百威(Carbosulfan)、阿维菌素(Abamectin)和锐劲特(Fpronil))对3种淡水浮游动物(大型溞(Daphnia magna)、萼花臂尾轮虫(Brachionuscalyciflorus)和尾草履虫(Paramecium caudatum))的急性毒性作用。通过单一急性毒性试验,检测了5种常用杀虫剂对3种淡水浮游动物的24 h(大型溞和萼花臂尾轮虫)和1 h(尾草履虫)半致死浓度(LC50)。结果表明,随杀虫剂质量浓度增加,5种杀虫剂的毒性均明显增强,3种浮游动物的死亡率上升,呈明显的浓度-效应关系。5种杀虫剂对大型溞的24 h-LC50依次为0.001 mg/L、0.000 001 mg/L、0.078 mg/L、0.001 mg/L、0.098 mg/L,毒性均为剧毒;对萼花臂尾轮虫的24 h-LC50依次为0.081 mg/L、0.003 mg/L、0.062 mg/L、0.005 mg/L、0.476 mg/L,毒死蜱、三氟氯氰菊酯、丁硫克百威、阿维菌素为剧毒,锐劲特为高毒;对尾草履虫的1 h-LC50依次为0.434 mg/L、1.904 mg/L、4.851 mg/L、4.024 mg/L、33.393 mg/L,毒死蜱表现为高毒,三氟氯氰菊酯、丁硫克百威、阿维菌素为中毒,锐劲特为低毒。3种淡水浮游动物对杀虫剂的敏感性从大到小依次为大型溞、萼花臂尾轮虫、尾草履虫。从敏感性来说,大型溞和萼花臂尾轮虫均为较好的进行杀虫剂水环境生态效应评价的受试动物;尾草履虫由于时效快,在毒死蜱的检测中可作为优先考虑的受试动物。     

Trends in Pesticide Use and Efficacy During 26 Years of Changing Agriculture in Southern England

We report on trends in agricultural pesticide use from1970 to 1995 inclusive in arable crops on the SouthDowns, West Sussex, U.K. Information is given on theproportion of cropped area treated with pesticides,the percentage spray area, the number of pesticideapplications per field, and the number of compoundsapplied per field for herbicides, foliar fungicidesand insecticides. Compared to national publishedfigures, our data are broadly representative of thenational picture; they provide a complete and detailedtime series whereas national figures are available foronly 7 out of the 26 yr. In general, the areatreated (fungicides, insecticides) and the intensityof use (all three types of pesticide) increased overthe 26 yr. The spectrum of activity of theherbicides applied to arable crops increased from anaverage of 22 weed taxa susceptible in 1970 to 38 weedtaxa susceptible in 1995. The odds on herbicide andfungicide use in break crops were, respectively, 93%and 99% lower than average; odds on insecticide usein spring cereals were 98% lower than average. Comparing winter wheat on the most traditional farm(grass/cereal rotation) with the most modern one(monoculture winter wheat), the proportion of fieldstreated with herbicides was similar, but the odds onbeing treated with fungicides were 129% higher on themodern farm. Insecticides were used in only 2% ofthe fields on the traditional farm, while on themodern farm over the same time period, 79% of thefields were treated. This fits previously observeddifferences in wildlife abundance on the two farms.     

Effect of Dursban 480 EC (chlorpyrifos) and Talstar 10 EC (bifenthrin) on the physiological and genetic diversity of microorganisms in soil

This investigation was undertaken to determine the impact of the insecticides Dursban 480 EC (with organophosphate compound chlorpyrifos as the active ingredient) and Talstar 10 EC (with pyrethroid bifenthrin as the active ingredient) on the respiration activity and microbial diversity in a sandy loam luvisol soil. The insecticides were applied in two doses: the maximum recommended dose for field application (15 mg kg^?1 for Dursban 480 EC and 6 mg kg^?1 for Talstar 10 EC) and a 100-fold higher dose for extrapolation of their effect. Bacterial and fungal genetic diversity was analysed in soil samples using PCR DGGE and the functional diversity (catabolic potential) was studied using BIOLOG EcoPlates at 1, 3, 7, 14, 28, 56 and 112 days after insecticide application. Five bacterial groups (α, β, γ proteobacteria, firmibacteria and actinomycetes) and five groups of fungi or fungus-like microorganisms (Ascomycota, Basidiomycota, Chytridiomycota, Oomycota and Zygomycota) were analysed using specific primer sets. This approach provides high resolution of the analysis covering majority of microorganisms in the soil. Only the high-dose Dursban 480 EC significantly changed the community of microorganisms. We observed its negative effect on α- and γ-proteobacteria, as the number of OTUs (operational taxonomic units) decreased until the end of incubation. In the β-proteobacteria group, initial increase of OTUs was followed by strong decrease. Diversity in the firmibacteria, actinomycetes and Zygomycota groups was minimally disturbed by the insecticide application. Dursban 480 EC, however, both positively and negatively affected certain species. Among negatively affected species Sphingomonas, Flavobacterium or Penicillium were detected, but Achromobacter, Luteibacter or Aspergillus were supported by applied insecticide. The analysis of BIOLOG plates using AWCD values indicated a significant increase in metabolic potential of microorganisms in the soil after the high-dose Dursban application. Analysis of respiration demonstrated high microbial activity after insecticide treatments; thus, microbial degradation was relatively fast. The half-life of the active insecticide compounds were estimated within the range of 25 to 27 days for Talstar and 6 to 11 days for Dursban and higher doses stimulated degradation. The recommended dose levels of both insecticides can be considered as safe for microbial community in the soil.     

Organochlorine levels in human blood from residents in areas of limited pesticide use in Sudan

Ninety-nine human blood samples were collected from the riverine region of northern Sudan and the traditional and mechanized rain-fed areas of western and eastern Sudan, representing areas of limited pesticide use in Sudan. Blood samples were analyzed for organochlorine pesticides by gas liquid chromatography (GLC) followed by electron-capture detection (ECD). p,p′-DDE (a metabolite of DDT), heptachlor epoxide, β-hexachlorocyclohexane (β-HCH), and dieldrin were detected in all locations surveyed. The level of total organochlorine burden was highest in the traditional rain-fed area, followed by the mechanized rain-fed area, and the riverine area. A highly significant correlation was observed between total organochlorine blood burden and the age of the donors (r = 0.608**).     

新烟碱类杀虫剂对蜜蜂的急性毒性及风险评价

为新烟碱类杀虫剂合理使用提供科学依据,本研究采用饲喂法和点滴法测定了9种新烟碱类杀虫剂对蜜蜂的急性毒性效应,且根据风险商值法进行了风险评价,氟啶虫酰胺和吡蚜酮作为对照药剂。试验结果表明:6种新烟碱类杀虫剂(噻虫胺、呋虫胺、吡虫啉、烯啶虫胺、氟啶虫胺腈和噻虫嗪)对蜜蜂经口和接触毒性的48 h-LD50值为1.73×10-3(1.37×10-3~2.45×10-3)~35.3×10-2(30.5×10-2~41.4×10-2)μg·蜂-1,均属于高毒级;其次为氯噻啉,该药剂对蜜蜂经口和接触毒性的48 h-LD50值为56.4×10-2(40.9×10-2~95.5×10-2)和2.05(1.13~3.18)μg·蜂-1,分别为高毒和中毒;而啶虫脒和噻虫啉对蜜蜂经口和接触毒性的48 hLD50值为2.57(1.94~3.75)~9.85(8.23~11.6)μg·蜂-1,为中毒级。对照药剂氟啶虫酰胺和吡蚜酮对蜜蜂经口和接触毒性的48h-LD50值均100μg·蜂-1,为低毒级。风险评价结果表明:噻虫胺、呋虫胺、吡虫啉、噻虫嗪、氯噻啉、烯啶虫胺和氟啶虫胺腈对蜜蜂具有不可接受的风险,啶虫脒、噻虫啉和对照药剂氟啶虫酰胺、吡蚜酮对蜜蜂的风险可接受。因此,在害虫综合治理中,应谨慎使用新烟碱类杀虫剂,以免对蜜蜂产生严重的毒副作用。     

The human serum paraoxonase—Polymorphism and specificity

Human serum contains EDTA‐sensitive (Ca⁺⁺‐dependent) and EDTA‐stable (albumin) paraoxonases which hydrolyse paraoxon, 0,0‐diethyl,0–4‐nitrophenyl phosphate.

In Caucasians the EDTA‐sensitive enzyme shows a genetically determined polymorphism which is governed by two alleles. In typical Mongoloid or Negro populations this polymorphism is expressed to a lesser degree, and in a few samples (e.g. Aborigines) it cannot be observed at all. The distribution of the activity of the EDTA‐stable (albumin) paraoxonase is unimodal.

Many authors supposed that paraoxonase is an arylesterase (EC 3.1.1.2) which means that it is also able to hydrolyse phenylacetate or β‐naphthylacetate. New investigations have shown that the human serum fractions splitting paraoxon can be separated from those hydrolysing phenylacetate and related substrates.

The polymorphism of the EDTA‐sensitive human serum paraoxonase can be applied to investigations concerning specificity. From this it becomes evident that this enzyme is rather specific. Already slight changes of the paraoxon molecule lead to a decrease of activity. On the other hand the enzyme seems to hydrolyse also phosphonic acid esters and 4‐nitrophenylacetate in the same way like paraoxon (polymorphism).

There is a linkage relationship of paraoxonase with cystic fibrosis and DNA markers. According to these results the (EDTA‐sensitive) paraoxonase locus is on the human chromosome 7.

A high serum paraoxonase level actually protects serum cholinesterase (EC 3.1.1.8) and has to be considered in biological monitoring of workers exposed to parathion.     

Induction of micronuclei in bone marrow cells and hepatotoxicity of one of the most common over-the-counter pyrethroid insecticide products in Nigeria

Increasing environmental pollution in the tropics is creating a breeding ground for mosquitoes, leading to increasingly frequent use of insecticides to combat home infestation of mosquitoes, the vector of malarial parasites. Household members are therefore more prone to aerosol exposure and subsequent health effects. We assessed the hepatotoxic and clastogenic effects in rats exposed to different levels of aerosols of one of the insecticides most commonly in used in Nigeria. There were significant (p?2 in the groups of rats exposed to the aerosols when compared with the control group. In addition, rats exposed to the insecticide aerosols have elevated activities of serum enzymes: γ-glutamyl transferase, aspartate amino transferase and alanine amino transferase, as well as number of micronuclei scored in the bone marrow, at levels that are significantly (p?相似文献   

4种农药对3种拟菊酯杀虫剂在不同光源下的光解效应

以太阳光、氙灯、高压汞灯为光源,研究了哒嗪硫磷、多菌灵、克百威、丁草胺4种农药对氯氰菊酯、溴氰菊酯、氰戊菊酯3种拟菊酯杀虫剂的光解速度及光解效应的影响。结果表明：哒嗪硫磷、多菌灵对氯氰菊酯等3种拟菊酯杀虫剂在3种不同光源的光照处理下均表现出光敏降解效应;然而在太阳光及高压汞灯光源的光照处理下,克百威和丁草胺对３种拟菊酯杀虫剂具有光猝灭降解作用。太阳光照射下氯氰菊酯等3种拟菊酯杀虫剂的光解率与其单位面积上的药剂剂量成反比;而哒嗪硫磷等4种农药对3种拟菊酯杀虫剂的光敏或光猝灭效率与此4种农药的剂量成正相关     

Determination of trace amounts of chlorinated insecticides and fungicides in ginseng using capillary gas chromatography and 63Ni electron capture detector

A method for the simultaneous determination of a series of chlorinated insecticides and fungicides as residues in ginseng is presented in this article. Pulverized samples are subjected to Soxhlet extraction with acetone-petroleum ether and the extract is partitioned between petroleum ether and aqueous sodium sulfate solution (2:98). The combined petroleum ether phase is cleaned up by sulfuric acid and analyzed by capillary gas chromatography using ⁶³Ni electron capture detector. Recoveries from the different concentrations for 11 kinds of chlorinated insecticides and fungicides are between 92.40 and 103.7% with coefficients of variations ranged 1.22 and 9.53% without samples, and between 89.00% and 104.10% with coefficients of variations between 1.16% and 9.16% with samples. The detection limits are 0.2- 7.0 ng/kg.     

大亚湾海域多氯联苯及有机氯农药研究

1999年 8月 4日采集了大亚湾次表层水、悬浮颗粒物和表层沉积物并用气相色谱 (电子捕集检测器 )分析了其中 12个多氯联苯 (PCBs)和 18个有机氯农药样品。总PCBs含量 ,水体中介于 91.1～ 135 5 .3ng/L ,沉积物中为 (0 .85～ 2 7.37)× 10 -9;总HCHs含量水体中介于 35 .5～ 12 2 8.6ng/L ,沉积物中则为 (0 .32～ 4 .16 )×10 -9;总DDTs含量在水体中介于 2 6 .8～ 975 .9ng/L ,沉积物中为 (0 .14～ 2 0 .2 7)× 10 -9;而在悬浮颗粒物中均未检出。水体和沉积物中DDT/(DDE DDD)比值较大 ,表明近期仍有此类化学物质输入大亚湾海域。本研究为大亚湾养殖海区提供难降解有机污染物的现状资料。