混配农药的联合毒性

混配农药指2种以上的农药按比例复配，旨在提高药效，延缓抗药性。为了解混配农药的毒性及其毒作用机制，有效地防治中毒，我们进行了混配农药的联合毒性实验研究和混配农药对大鼠全血胆碱酯酶活性影响的研究。     

阿维菌素与有机磷农药急性毒性的分析

阿维菌素是一种生物化学农药，属于第三代农药杀虫剂，现在很多厂家开发阿维菌素类与有机磷类或菊酯类农药的混配制剂，来发挥各自的优点，使新的制剂高效，低毒，无残留，易降解。市场应用非常广阔。本试验的目的是通过急性毒性试验的中毒症状来探讨两种农药毒作用机制的差异。     

混配农药中毒的流行病学研究

目的 查明混配农药中毒的发病水平和农药中毒的危险因素。方法 采用整群抽样方法,在江苏省和山东省的3个乡随机抽取25个行政村,按大约l：l的人数比例分为研究组(12个行政村)与对照组(13个行政村)。研究组施药员使用有机磷与菊酯类的混配农药,对照组施药员使用单一有机磷农药。在观察期内喷洒过农药的施药员均为调查对象。中毒病例经高年资职业病医师讨论核实后加以确认。结果 研究组2179名施药员,中毒率为10．1‰;对照组2615名施药员,中毒率为2．29‰,研究组中毒率高于对照组,其差异有非常显性。调整其他中毒危险因素后,使用混配农药的中毒危险是使用单一农药的3．45倍。农药中毒的其他危险因素还有：工间吸烟或进食、喷雾器发生故障或滴漏、施药后不能尽快清洗全身、个人防护不严密、长时间施药、女性施药和喷洒棉花。结论 如果单剂农药混配后毒性表现为协同或相加作用,则混配用药发生农药中毒的危险增大。应加强对施药员的健康教育和用药技术培训。     

混配农药致豚鼠皮肤变态反应的观察

农药的合理混配使用在扩大防治范围、增强药效、克服抗药性、降低毒性及增加经济效益等方面都具有重要作用 ,也是我国近年来农药发展的主要趋势。混配农药已成为近年来我国生产使用的主要农药剂型 ,它在增强杀灭害虫作用的同时 ,也可能增加对接触人群健康的潜在危害。混配农药无论在其毒作用机制代谢途径还是中毒防治等方面均有其特殊及复杂的一面[1] 。因此 ,为了安全生产和使用混配农药 ,保护接触者的健康 ,我们对新研制的 8种混配农药进行了豚鼠皮肤变态反应 (致敏 )作用观察 ,结果如下。1　材料与方法1 1　样品　 2 5 %辛·甲氰乳油、6%…     

1起混配农药中毒事故调查分析

目的 探索和完善混配农药中毒防控机制,切实保障从业人员的身体健康.方法 对莒南县某农药厂三名混配农药甲拌辛中毒病例进行流调,对该农药厂进行现场卫生学调查.结果 三名职工在2010年4月6日至2010年4月11日之间发生了亚急性中度有机磷混配农药中毒.结论 该农药厂应专人负责完善并落实职业病防护的有关制度和措施,严防类似混配农药中毒事件的再次发生.     

江苏省混配农药中毒流行病学调查报告

目的为研究混配农药中毒的发病情况和危险因素,提出预防方案以降低混配农药中毒发病率.方法对1102名混配农药施药者(接触组)和1 260名单一农药施药者(对照组)进行了流行病学调查.结果接触组中毒发病率显著高于对照组(P＜0.05),接触组与对照组在施药前后血红细胞胆硷酯酶抑制无显著性差异,施药多少、操作方式等指标是影响农药中毒发生的危险因素.结论接触混配农药发生中毒的危险性比有机磷单一农药高4.5倍.并提出了预防措施.     

混配家用卫生杀虫剂的安全性评价

目的评价混配家用卫生杀虫剂的安全性。方法按GB 15670-1995《农药登记毒理学试验方法》对15种混配家用卫生杀虫剂进行急性经口、吸入毒性试验,家兔眼刺激试验及家兔皮肤刺激试验。结果15种混配家用卫生杀虫剂急性经口、吸入毒性均为微毒级,对眼刺激强度及皮肤刺激均为低毒级。结论混配家用卫生杀虫剂属微毒农药制剂,用水作混配家用卫生杀虫剂的载体是发展的方向。     

某省五年被鉴定农药样品的特点分析

目的 对河北省2002至2006年受检的农药毒性鉴定样品的特点进行分析,为防治提供依据.方法 对5年中664份受检的农药毒性鉴定样品的种类、毒性等特点进行分析.结果 农用杀虫剂是目前研制、生产的主流,占检品的52.7%,卫生杀虫剂占22.O%,低毒农药占受检样品的70.8%;新型农药阿维菌素占农用杀虫剂的24.9%,高于传统有机磷农药的19.1%.结论 农用杀虫剂是目前河北省农药生产的主要农药,以低毒农药为主,应关注新型农药的毒理学研究.     

混配家用卫生杀虫气雾剂17种的毒性研究

目的对17种混配家用卫生杀虫气雾剂进行毒性研究。方法按GB15670—1995（农药登记毒理学试验方法》对17种混配杀虫气雾剂进行急性经口、吸入毒性试验，家兔眼刺激试验及家兔皮肤刺激试验。结果17种混配家用卫生杀虫气雾剂急性经口、吸入毒性除1种为低毒级外，其余均为微毒级；该次实验对其中6种气雾剂进行眼刺激及皮肤刺激试验均显示无刺激性。结论混配家用卫生杀虫气雾剂一般属微毒农药制剂，经口、吸入的毒性较小，对眼睛、皮肤的刺激性也较小。     

山东省昆配农药使用现况的调查

目的摸清山东省混配农药使用现况,提出相应的农药中毒防治措施.方法以整群抽样的流行病学调查方式确定调查范围,观察期末对辖区内所有施药员进行问卷调查.结果共收录完整问卷2 503份.施药员使用单一农药的1 405人(占56.13%),使用混配农药的1 095人(占43.87%).使用混配农药者中自配的748人(占68.12%)、使用市售制剂的350人(占31.88%).农药混配品种主要是有机磷加另一种有机磷、有机磷加拟除虫菊酯类或三元混配等.单一农药中毒罹患率0.71%,混配农药中毒罹患率1.82%(x2=6.41,P＜0.025,RR=2.56,95%CI=1.20～5.47,AR=1.11%,ARP=60.94).结论混配用药可能使农药中毒发生的机会增加,中毒原因主要与不合理混用及缺少必要的防护措施有关.     

High-performance liquid chromatographic method for the determination of occupational exposure to the pesticide abamectin

As part of a survey of occupational exposure to pesticides in greenhouses for growing ornamentals, analytical methods were developed and validated for the measurement of exposure of workers to the pesticide abamectin. Abamectin consists of a mixture of avermectin-B1a and avermectin-B1b, which are members of a class of fermentation products of the soil microorganism Streptomyces Avermitilis. Because of the high molecular weight of the avermectins (greater than 800 daltons), high-performance liquid chromatography (HPLC) was the analytical method of choice. Previously described HPLC methods that used fluorescence detection were adapted and validated for the determination of dermal exposure by the analysis of cotton gloves and foliar dislodgeable residue. IOM samplers (developed at the Institute of Occupational Medicine, Edinburgh, U.K.) for collecting the inspirable fraction of dust or aerosols were tested for the determination of airborne abamectin concentrations in greenhouses. An analytical procedure considerably simpler than published methods appeared suitable for the determination of abamectin residues on cotton gloves and on greenhouse foliage. Analytical recovery from cotton gloves, solutions of foliar dislodgeable residues, and air-sampling filters was essentially complete. However, air concentrations of abamectin could not be reliably measured by using the IOM sampling device because of breakdown during sampling. Between-day coefficients of variation for solutions of dislodgeable residue and cotton glove extracts were between 3% and 6% for abamectin concentrations between 5 and 140 micrograms/L.     

4种农药对斑马鱼的急性毒性与安全评价

目的研究4种农药对斑马鱼的毒性,为其安全使用提供依据。方法以斑马鱼为试材,采用半静态法在室内测定4种农药对斑马鱼的急性毒性并对其进行安全评价。结果 93%丁草胺原药的LC50为0.35mg/L,属高毒级农药;1.8%阿维菌素水乳剂、50%乙草胺乳油、25%咪鲜胺乳油96h的LC50分别为1.08、5.45、5.81mg/L,属中毒级农药。结论该研究为农药的安全合理使用提供了基础资料和科学依据。     

Differential sensitivity of two green algae,Scenedesmus obliqnus and Chlorella pyrenoidosa,to 12 pesticides

Growth-inhibiting tests were carried out for 12 pesticides (including 11 fungicides: fosetyl-aluminum, benomyl, metalaxyl, iprodione, dimetachlone, carbendazim, thiophanate-methyl, bismerthiazol, procymidone, zineb, chlorothalonil, and the acaricide abamectin) in the green algae Chlorella pyrenoidosa and Scenedesmus obliqnus and the differential sensitivities of the two green algae to those pesticides were compared. The results indicate that the acute toxicity of benomyl to C. pyrenoidosa and S. obliqnus is the highest among all of the pesticides tested and is close to that of the photosynthesis-inhibiting herbicides atrazine, simazine, and chlorotoluron. Meanwhile, algal species vary widely in their response to the pesticides. The results demonstrated that there was a differential response to various pesticides by the two species of algae and that the sensitivity of various species of algae exposed to chlorothalonil varied by nearly two orders of magnitude; sensitivity to thiophanate-methyl varied by more than one order. Investigations using different algal species as test organisms have demonstrated that algae vary greatly in their response to chemicals. Differential sensitivity of green species to the compounds could induce species shifts within communities.     

Pesticide use and poisoning among farmers from the county of Paty do Alferes, Rio de Janeiro, Brazil

This survey is part of a more comprehensive study on the health consequences of pesticide exposure. In the county (municipality) of Paty do Alferes, Rio de Janeiro State, Brazil, 55 agricultural workers were interviewed on the use of pesticides, use of personal protective equipment, data on health status, and symptoms related to pesticide exposure, disposal of agrochemical containers, and technical assistance. The most widely used pesticides were insecticides such as abamectin, organophosphate compounds, and pyrethroids, and fungicides such as mancozeb, chlorothalonil, and copper products. As a rule, pesticides are handled carelessly, and 92% of workers involved in the mixing, loading, and spraying of insecticides and fungicides used no protective clothing or equipment whatsoever. Some 62% of workers reported at least one illness associated with mixing or spraying pesticides. The most frequently reported symptoms were headache, nausea, vomiting, dizziness, skin irritation, and blurred vision, and 21% of affected workers required medical care. In more than half (51%) of the cases, workers reported using organophosphate insecticides from toxicological class I when they felt sick.     

混配农药施药员的生物监测

目的 探讨混配农药中的拟除虫菊酯对有机磷抑制红细胞乙酰胆碱酯酶（AChE）作用的影响。方法 在江苏和山东省随机选择1周内未接触任何农药的健康施药员作为生物监测对象,其中,混配农药组（简称混配组）65人,使用甲胺磷与溴氰菊酯（江苏省）或甲基对硫磷与氯氰菊酯（山东省）混配的农药;单一农药组（简称单一组）67人,使用甲胺磷（江苏省）或甲基对硫磷（山东省）。喷药时间为2h,其个人防护等外部条件均与本地平常情况一致。同时在当地乡镇卫生院随机选择未接触农药的健康医务人员2人为对照组。使用硫代乙酰胆碱二硫代双硝基苯甲酸（DTNB）分光光度法,分别测定喷药前、喷药后即刻和喷药后1h的红细胞AChE活力。结果 喷药后混配组和单一组的红细胞AChE活力均受到抑制,与喷药前相比差异有高度显著性（P＜0．01）;红细胞AChE活力的喷药后即刻抑制率和喷药后1h恢复率,混配组均高于单一组,但差异均无显著性（t=－0．9270,df=64.1,P=0.3574;t=-1.3413,df=64.3,P=0.1845)。结论 本次监测未观察到混配农药中的拟除虫菊酯对有机磷抑制红细胞AChE活力的作用有明显影响。     

Toxicity of Sediment-Associated Pesticides to <Emphasis Type="Italic">Chironomus dilutus</Emphasis> and <Emphasis Type="Italic">Hyalella azteca</Emphasis>

Two hundred sediment samples were collected and their toxicity evaluated to aquatic species in a previous study in the agriculturally dominated Central Valley of California, United States. Pyrethroid insecticides were the main contributors to the observed toxicity. However, mortality in approximately one third of the toxic samples could not be explained solely by the presence of pyrethroids in the matrices. Hundreds of pesticides are currently used in the Central Valley of California, but only a few dozen are analyzed in standard environmental monitoring. A significant amount of unexplained sediment toxicity may be due to pesticides that are in widespread use that but have not been routinely monitored in the environment, and even if some of them were, the concentrations harmful to aquatic organisms are unknown. In this study, toxicity thresholds for nine sediment-associated pesticides including abamectin, diazinon, dicofol, fenpropathrin, indoxacarb, methyl parathion, oxyfluorfen, propargite, and pyraclostrobin were established for two aquatic species, the midge Chironomus dilutus and the amphipod Hyalella azteca. For midges, the median lethal concentration (LC₅₀) of the pesticides ranged from 0.18 to 964 μg/g organic carbon (OC), with abamectin being the most toxic and propargite being the least toxic pesticide. A sublethal growth endpoint using average individual ash-free dry mass was also measured for the midges. The no–observable effect concentration values for growth ranged from 0.10 to 633 μg/g OC for the nine pesticides. For the amphipods, fenpropathrin was the most toxic, with an LC₅₀ of 1–2 μg/g OC. Abamectin, diazinon, and methyl parathion were all moderately toxic (LC₅₀s 2.8–26 μg/g OC). Dicofol, indoxacarb, oxyfluorfen, propargite, and pyraclostrobin were all relatively nontoxic, with LC₅₀s greater than the highest concentrations tested. The toxicity information collected in the present study will be helpful in decreasing the frequency of unexplained sediment toxicity in agricultural waterways.     

Risk assessment of dermal exposure of greenhouse workers to pesticides after re-entry

On 18 farms for rose culture in greenhouses in The Netherlands, dermal exposure of hands and forearms to abamectin (avermectin B₁), dodemorph (4-cyclododecyl-2,6-dimethylmorpholinium acetate) and bupirimate (5-butyl-2-(ethylamino)-6-methyl-4-pyrimidinyl dimethylsulphate) was measured during crop activities. Dermal exposure during cutting (75 workers) amounted to 13 g/h, 1.8 mg/h, and 2.2 mg/h for abamectin, dodemorph and bupirimate, respectively. Dermal exposure to abamecting and dodemorph during sorting (21 workers) and bundling (30 workers) was comparable with that during cutting. From the dependence of dermal exposure on the amount of dislodgeable foliar residue (DFR) a transfer factor was estimated to be 1,200, 4,550, and 2,400 cm²/h for abamectin, dodemorph and bupirimate, respectively. For sorting and bundling these factors were of the same order of magnitude. The results suggested that work rate was also a determinant of dermal exposure.The within-farm variance of dermal exposure during cutting appeared to account for approximately 30% of the unexplained part of the variation remaining after regression on DFR and application technique. The final unexplained part in the variation of dermal exposure during cutting was amongst others due to the variation between the different farms in which the measurements were performed.A health risk evaluation of the observed levels of dermal exposure after re-entry of greenhouses led to the conclusion that a health hazard may exist, especially after application of high rates of relatively toxic pesticides which easily penetrate the skin.     

谈我国混配农药中毒的预防对策

根据流行病学现场调查发现的具体问题,提出预防混配农药中毒的对策：禁止无原则、无实验根据的随意混配;禁止或限制生产和使用高毒混配农药;严格规范混配农药标签的内容及形式;加强对农药市场的监督管理,严禁非法生产和经销混配农药;探索和推广由专业人员统一负责的集中施药模式;加强对施药员的技术培训,提高用药的科学性;加强对施药员的健康教育,提高其自我防护意识。     

杀虫剂复配对淡色库蚊杀灭效果的实验研究

目的探讨杀虫剂复配对淡色库蚊的杀灭效果，为合理有效地进行蚊虫化学防治提供依据。方珐参照WHO生物测定方法和唐振华药物联合作用试验方法。结果对于DDVP、残杀威、氯氰菊酯、三氯杀虫酯4种化学杀虫剂，分别选择2种作用机制不同的杀虫剂复配对抗DDVP、抗残杀威和抗氯氰菊酯3种抗性品系淡色库蚊均起到明显的杀虫增效作用，DDVP和残杀威2种作用机制相同的杀虫剂复配对抗DDVP品系淡色库蚊无明显的杀虫增效作用。结论作用机制不同的杀虫剂复配可对蚊虫起到明显的杀虫增效作用，作用机制相同的杀虫剂复配对蚊虫无明显的杀虫增效作用，选择杀虫效力较强的配方可提高蚊虫防治效果。     

Assessment of antifertility activities of abamectin pesticide in male rats

The effects of abamectin pesticide on fertility of adult male Sprague-Dawley rats were investigated. Adult male rats were exposed to tap water containing 0, 571, 857, or 1714 ppm abamectin for 6 weeks. Based on fluid consumption, animals received 0, 1.19, 1.87, and 2.13 mg/animal/day abamectin, respectively. Fertility was significantly reduced in male rats ingesting abamectin at all three doses in that the number of females impregnated by them was significantly reduced. The number of viable fetuses was significantly reduced in females mated with males that ingested abamectin at 1.87 or 2.13 mg/animal/day. Significant increases in the total number of resorptions and the number of females with resorptions were observed in females mated with the exposed males at all three concentrations. The body weight gain and water consumption were significantly lower in males that ingested 2.13 mg/animal/day abamectin. Likewise, ingestion of abamectin at all three concentrations caused a significant increase in the weight of testes. Epididymal and testicular sperm counts and daily sperm production were significantly decreased in exposed males. The serum level of testosterone was significantly reduced, whereas the serum level of follicle-stimulating hormone was significantly increased in males that ingested abamectin at a concentration of 2.13 mg/animal/day. Histological evaluation of the testes revealed several abnormalities including infiltration with congested blood vessels with marked hemorrhage and a significant accumulation of connective tissue surrounding the seminiferous tubules. These results strongly suggest the adverse effects of abamectin pesticide on male rat fertility.