典型杀虫剂类内分泌干扰物对水生溞类的毒性效应研究进展

内分泌干扰物(endocrine disrupting chemicals, EDCs),尤其是具有内分泌干扰效应的杀虫剂,因能显著影响水生生物的生长发育和生殖系统,其潜在生态毒性效应引起了人们的广泛关注。溞类在水生生态系统食物链中起着重要的连接作用,更易受到水体中残留的杀虫剂类EDCs的影响,其毒性效应在水生生态系统毒理学研究中有着重要的意义。本文重点综述了杀虫剂类EDCs对溞类产生的生长发育毒性和生殖毒性,从酶活性变化角度分析由此产生的氧化应激和神经毒性,并在基因表达水平上揭示其毒性作用机制,发现杀虫剂类EDCs通过扰乱神经系统和内分泌系统发挥作用,并展望了杀虫剂EDCs在联合毒性、多代效应的研究前景,旨在为研究杀虫剂类EDCs对大型溞的毒性作用和生态环境风险评估提供依据。     

8种拟除虫菊酯农药对稀有鲫的急性、亚慢性毒性研究

８种拟除虫菊酯对稀有鲫的急性毒性和其中２种拟除虫菊酯的亚慢性毒性研究结果表明：溴氰菊酯、高效氯氰菊酯、氯氰菊酯、甲氰菊酯、氰戊菊酯、二氯炔戊菊酯、胺菊酯、甲醚菊酯对稀有鲫均属剧毒,它们的ρ（９６ｈＬＣ５０）／μｇ·Ｌ－１分别为３．１６,３．２４,６．３１,７．２１,７．３５,３２．４５,９１．７５和８８２．６;甲氰菊酯、二氯炔戊菊酯对稀有鲫７ｄ亚慢性毒性的最低有影响浓度ρ（ＬＯＥＣ）和最高无影响浓度ρ（ＮＯＥＣ）分别为０．８８～０．４４μｇ／Ｌ,４．０～２．０μｇ／Ｌ,以ρ（９６ｈＬＣ５０）／μｇ·Ｌ－１为基准,２种拟除虫菊酯的安全系数均为０．０６～０．１２５．     

农药内分泌干扰效应研究进展

农药作为农业生产过程中的一类重要生产资料,主要用作杀虫剂、杀菌剂和除草剂等。由于农药的大量使用,目前在各类农产品及各种环境介质中都能被检测到,对饮食健康和环境安全带来潜在危害。研究发现,许多农药为内分泌干扰物,其能够干扰人类和其他生物体的内分泌系统正常功能。本文在总结国内外相关研究的基础上,对农药内分泌干扰效应的作用机理及筛选模型进行总结,对有机氯、有机磷和拟除虫菊酯等各类农药的内分泌干扰效应研究进展进行综述,并提出深入探究农药致毒作用机制和低剂量下多种农药联合毒性是本领域的重要研究方向。     

农药内分泌干扰效应研究进展

农药作为农业生产过程中的一类重要生产资料,主要用作杀虫剂、杀菌剂和除草剂等。由于农药的大量使用,目前在各类农产品及各种环境介质中都能被检测到,对饮食安全和环境健康带来潜在危害。研究发现,许多农药为内分泌干扰物,其能够干扰人类和其它生物体的内分泌系统正常功能。本文在总结国内外相关研究的基础上,对农药内分泌干扰效应的作用机理及筛选模型进行总结,对有机氯、有机磷和拟除虫菊酯等各类农药的内分泌干扰效应研究进展进行综述,并提出深入探究农药致毒作用机制和低剂量下多种农药联合毒性是本领域的重要研究方向。     

DINP的健康效应及机理研究进展

增塑剂邻苯二甲酸二异壬酯(di-isononyl phthalate,DINP)广泛应用于聚氯乙烯塑料消费品和工业产品中,因其对人体多个系统均有毒性作用,DINP的健康效应成为研究热点.笔者对近年来国内外的相关研究进行综述,对DINP的内分泌毒性、生殖发育毒性、心血管毒性、免疫毒性及神经毒性等多种毒作用及机理进行了系统阐述,并针对存在的问题进行了总结和展望,有望为环境DINP相关的人体健康效应及防治提供参考.     

全氟化合物发育神经毒性研究进展

全氟化合物(PFCs)在工业生产和生活中广泛应用,已成为环境中一类普遍的污染物。由于PFCs污染表现出全球性、持久性和富集性等特征,其毒性备受关注。近期研究结果显示,PFCs除对肝脏、免疫系统和生殖内分泌系统等有明显影响外,还具有发育神经毒性。在总结了近年来PFCs发育神经毒性的研究进展基础上,讨论了PFCs发育神经毒性可能的几个机制,并且分析该领域研究存在的问题,提出应该加强环境相关剂量下PFCs发育神经毒性研究,关注PFCs与其他神经毒物复合暴露的发育神经毒性,以推进对实际环境中PFCs所产生的神经损伤的认识。     

联苯菊酯暴露对雌性褐菖鲉卵巢发育的影响及其毒性机制

联苯菊酯是农业、园林等领域应用广泛的拟除虫菊酯类杀虫剂,然而有关联苯菊酯对鱼类生殖毒性的研究却很少。以常见的近海鱼类褐菖鲉为受试对象,探讨联苯菊酯对鱼类卵巢发育的影响及机制。褐菖鲉在以环境相关浓度(1、10、100 ng·L~(-1))的联苯菊酯暴露50 d后,各暴露组卵巢生殖细胞发育均受到显著抑制,卵巢17β-雌二醇与睾酮含量均出现下降,caspase-3活性呈剂量依赖性上升。相对定量PCR分析显示,卵巢雌激素受体(ERβ)mRNA水平下降。结果表明,联苯菊酯诱导细胞产生凋亡,导致雌、雄激素水平和雌激素受体表达下降,环境剂量作用下对褐菖鲉卵巢发育具有显著影响。     

邻苯二甲酸二乙基己酯(DEHP)污染及其毒性研究进展

邻苯二甲酸二乙基己酯(DEHP)作为重要的增塑剂被广泛应用于涂料、食品包装、医疗器材、儿童玩具等产品中。研究表明DEHP在水、土壤、空气等各个环境要素以及食物、饮用水中已被普遍检出,并对环境产生潜在的危害。本文通过分析国内外DEHP的环境暴露和毒性效应的研究成果,总结了DEHP在室外大气、室内空气、土壤、地表水、地下水、食品和饮用水中的污染现状,并对DEHP的替代产品进行总结;此外,本文深入探讨了DEHP对水生生物和陆生生物的生态毒性效应,以及对生殖发育、肝脏、呼吸系统和神经系统等的健康毒性效应。最后,结合DEHP在环境暴露调查和毒性效应研究方面的不足,指出需要进一步加强我国DEHP的环境暴露调查,制定相关环境基准值与标准限值,开展慢性生态毒性效应和人体健康毒性效应等方面的研究。     

7种拟除虫菊酯农药对卤虫的急性毒性研究

为了研究7种拟除虫菊酯农药对美国大盐湖卤虫(GSL Artemia)的急性毒性效应,挑选18~24 h内孵出的卤虫,继续培养24 h后得到Ⅱ~Ⅲ龄卤虫无节幼体,将其暴露于所设浓度梯度的拟除虫菊酯溶液中进行24 h急性毒性实验,记录卤虫无节幼体在各浓度溶液中的死亡情况,并将所得数据进行Probit分析。结果表明,卤虫对不同拟除虫菊酯的敏感性相差较大。氯菊酯、氯烯炔菊酯、炔咪菊酯、胺菊酯、联苯菊酯、高效氯氟氰菊酯和溴氰菊酯对卤虫的24 h半致死浓度(24 h-LC50)分别为4.68、14.82、18.12、38.21、>100、>100和>100 mg.L-1。因此,在含有卤虫的盐水环境中,应尽量避免使用毒性较高的氯菊酯,而选择使用联苯菊酯、高效氯氟氰菊酯和溴氰菊酯等毒性较低的农药。     

除虫菊酯和迷迭香对大鼠大脑突触体ATP酶的活性影响

除虫菊酯越来越广泛地被应用于农业和家庭昆虫防治,主要通过作用于膜结合蛋白而对动物起神经毒性.迷迭香因其抗氧化功能而被应用于很多商业化的除虫菊酯产品中.本实验以大鼠大脑突触体ATP酶为研究对象,对除虫菊酯和迷迭香的药理学进行了研究.用Percoll梯度离心法分离突触体,通过检测无机磷的量来测定总ATP酶和Mg2 -ATP酶活性.结果表明,除虫菊酯在浓度为10 μmol/L时总ATP酶和Mg2 -ATP酶分别降低到对照的80.3%和46.9%.迷迭香在浓度为0.3～30 μmol/L时几乎不影响ATP酶活性,当浓度上升到3 000 μmol/L时,总ATP酶活性降低到66.8%,而Mg2 -ATP酶活性降低到54.5%. 10 μmol/L 除虫菊酯和30 μmol/L迷迭香混合物引起总ATP酶和Mg2 -ATP酶分别降低到72.9%和33.4%.结论: 1) 除虫菊酯能抑制大鼠大脑ATP酶活性; 2) 迷迭香只在高浓度下才对ATP酶有抑制作用; 3) 迷迭香能增强除虫菊酯对ATP酶的抑制作用.图3参19     

抗生素与三唑类杀菌剂混合物对羊角月牙藻的长期毒性相互作用研究

地表水中抗生素与农药的混合暴露及其潜在生态与健康风险受到广泛关注。然而,目前关于抗生素与农药混合毒性研究大多仅考虑急性毒性,缺乏其长期毒性相互作用的研究。以较为广泛使用的2种抗生素土霉素(OXY)、环丙沙星(CIP)和1种三唑类杀菌剂农药戊唑醇(TCZ)及其二元混合物为研究对象,以生态系统中初级生产者绿藻(羊角月牙藻)为受试生物,研究目标混合物在暴露时间为96、120、144和168 h的长期毒性相互作用。结果表明,单一物质及其混合物随暴露时间延长而毒性增大;同一暴露时间点的单一污染物毒性大小顺序为OXYTCZCIP;混合物毒性相互作用与浓度、混合物组分和暴露时间三者密切相关;混合体系的拮抗作用均出现在高浓度区域,而中、低浓度区域呈协同作用或加和作用; OXY-CIP与CIPTCZ混合体系的协同作用随着暴露时间延长而协同作用逐渐增大。研究结果对水环境中抗生素与农药复合污染生态风险评估具有重要的现实意义。     

新烟碱类农药的污染现状及转化行为研究进展

新烟碱类(neonicotinoids)农药自在20世纪80年代中期引入以来,便发展成为世界上使用最广泛的一类杀虫剂。近年来,该类化合物在环境中被不断检出,并通过饮用水和食物等方式进入食物链,给人类健康带来极大的安全隐患。文章综述了新烟碱类杀虫剂在空气、土壤、水相、生物体和人体中的暴露浓度,以及这类农药在环境中的转化行为。目前针对新烟碱类杀虫剂的环境暴露研究仍十分有限,需要更全面调查其在多环境介质中的暴露状况以综合评价其生态风险。关于新烟碱类化合物的毒理学研究主要集中在急性毒性试验,而对于其他形式的毒性效应有待进一步研究。最后对新烟碱农药未来的研究重点和方向提出了展望。     

卫生用农药对居室环境影响与评价

研究了以拟除虫菊酯类农药为主要配方的各种类型卫生用农药在居室介质材料上的降解速率及残留时间。试验表明，拟除虫菊酯类农药对家蚕毒性极大。推荐ＳＯＳ／Ｕｍｕ原位法测定家庭卫生用农药的致遗传毒性，该法简便、准确，并能根据酶诱导率了解毒性程度，剂量－反应关系明显。     

Efficacy of fenvalerate as contact poison against the larval development and viability of mutant form (Sepia) of Drosophila melanogaster (Meigen)

Fenvalerate, a synthetic pyrethroid, was analysed for its toxic effects on Drosophila melanogaster. It has been estimated that LC50 0.0166 micro 1/100 ml food is threshold of lethality. These studies have also revealed that fenvalerate is toxic as it had a pronounced effect on the rate of development and viability.     

Cytotoxicity assessment of monocrotophos in Paramecium caudatum and Oxytricha fallax

Experiments were conducted to evaluate the toxic effects ofmonocrotophos in ciliate models Paramecium caudatum and Oxytricha fallax. In acute toxicity studies higherconcentrations of monocrotophos caused marked increase in mobility of cells exhibiting rocking movements within two mins of exposure but were decreased after 30 mins. LC50 value by mortality curve for 3 hr acute toxicity test of Oxytricha fallax and Paramecium caudatum was found 307.744 +/- 33.27 mg l(-1) and 332.284 +/- 57.52 mg l(-1) respectively. Oxytricha fallax was found sensitive than Paramecium caudatum to monocrotophos. In acute exposure cells showed deformities such as swelling, oval shaped deformity and in higher concentrations shortening of longitudinal axis with blackening of cytoplasm occurred. The length of paramecia was reduced prominently. Similarly enlargement of contractile vacuole and stress egestion of food vacuoles was also observed. The morphological studies showed the changes in shape, size, colour and width of Paramecia and Oxytricha. Frequencies of macronuclear aberrations were significant showing deformities such as rod shaped, elongation, fragmentation, diffusion and total absence of nucleus and were concentration dependent. The data provided in the present study on interaction of pesticides with nuclear structure can be of immense value because most of these pesticides have been reported to have carcinogenic, mutagenic and teratogenic properties.     

Persistence and dissipation of synthetic pyrethroid pesticides in red soils from the Yangtze River Delta area

Laboratory incubation trials were conducted to investigate the effects of several factors on the persistence as well as the dissipation of three synthetic pyrethroid pesticides in red soils obtained from the Yangtze River Delta region in China. The pyrethroids selected for investigation were cypermethrin, fenvalerate, and deltamethrin, which continue to be used extensively to control pests on farmland in the region despite the concern that they are highly toxic to certain vertebrate and mammalian species. Data from this exploratory study showed that the dissipation half-lives (T _1/2) tended to correlate with soil pH and soil organic matter contents, but not with soil cation-exchange capacity. The T _1/2 values were seen to be shorter in soil samples fertilized with glucose than without. The rates of pyrethroid dissipation also tended to increase with increasing initial soil concentration, but were largely unaffected by whether the pesticides were present in the soil separately or as a mixture. Another noteworthy observation is that microbial activity appeared to dominate the degradation process. Findings of this type could offer valuable clues for future research directions in reducing pesticide persistence in soil, which in turn could lead to the ultimate reduction of environmental pollution caused by pyrethroid application to farmland in the region. Project supported by Chinese Academy of Sciences (Project No. KSCX2-YW-N-038) and the National Key Basic Research Support Foundation (973), China (No. 2002CB4108010).     

Toxicity of the pyrethroid bifenthrin insecticide

Bifenthrin is a chiral synthetic pyrethroid insecticide that has been commonly used for agricultural and domestic pest control over the past decades. Due to its widespread application, residues of bifenthrin has been frequently detected in environmental media, residential areas and biota, thus posing potential risks to the health of wildlife and humans. In particular, bifenthrin exhibits high acute lethal toxicity to aquatic species, and it is the primary contributor to the toxicity of insecticides in waters. Additionally, bifenthrin can also cause sublethal toxic effects on various non-target organisms, including developmental toxicity, neurobehavioral toxicity, oxidative damage, immune toxicity and endocrine disrupting effects. Here we review recent studies about the fate of bifenthrin in the environment and biological systems, the toxicity of the chiral parent compound bifenthrin and the toxic effects of main metabolites. The adverse effects of bifenthrin, identified from both in vitro and in vivo studies, and the potential underlying mechanisms are presented. We discuss the enantiomeric difference in the toxicological effects of bifenthrin, since enantiomers of chiral compounds show different interactions with biological systems. Pyrethroid insecticides metabolites are not acutely toxic, but they have sublethal toxicity, such as endocrine disrupting effects and immunotoxicity. We provide emerging evidence for toxic effects of several main metabolites.     

Effect of agrochemicals on earthworms

This review describes the toxic effects of agrochemicals on earthworms. Carbamates are described as extremely toxic to earthworms in comparison to organophosphorus insecticides. Some pesticides have drastic effect on the nervous system of the earthworm. Earthworm can accumulate heavy metals from the soil in higher levels than any other animal. Mercury is twenty times more toxic than chromium.