新烟碱类杀虫剂对非靶标生物毒性效应的研究进展

Advances in Research on Toxic Effects of Neonicotinoid Insecticides on Non-target Organisms

新烟碱类杀虫剂是目前全球市场占有率最高的一类杀虫剂,它们选择性作用于昆虫烟碱型乙酰胆碱受体,以往普遍认为其对非靶标生物毒性较低。然而,越来越多的证据表明,新烟碱类杀虫剂的暴露会对非靶标生物造成负面影响。本文综述了新烟碱类杀虫剂对水生生物、非靶标昆虫、鸟类和哺乳动物等多种非靶标生物的毒性,以及对人类健康的影响。新烟碱类杀虫剂对各类生物均具有急性致死毒性,但不同物种之间半数致死浓度(LC50)或半数致死剂量(LD50)差别较大,由低至高依次为昆虫(0.01~2.38 mg·L^-1,3.7~81 ng·bee^-1)、甲壳动物(0.59~37.75 mg·L^-1)、鱼类(1.2~241 mg·L^-1)、鸟类(15~>2000 mg·kg^-1)和哺乳动物(82~>5000 mg·kg^-1)。新烟碱类杀虫剂对非靶标生物的亚致死毒性表现在降低繁殖力和生长速度、降低活动性、影响神经系统、扰乱代谢平衡、损伤DNA等。总体上看,吡虫啉的毒性最高,呋虫胺和烯啶虫胺的毒性较低。啶虫脒、噻虫啉、噻虫嗪和噻虫胺的毒性大小顺序随物种不同而不同。对于水生生物和非靶标昆虫,噻虫啉和噻虫胺的毒性较高,而对于鸟类和哺乳动物,啶虫脒的毒性较高。最后针对现有研究的不足,提出了今后的研究方向,以期为该类杀虫剂的风险评估和合理施用提供科学依据。

Neonicotinoid insecticides have become the most widely used class of insecticides in the global market.These insecticides act selectively on insect nicotinic acetylcholine receptors,and thus they were generally considered to be less toxic to non-target organisms.However,there is increasing evidence that exposure to neonicotinoid insecticides can have a negative impact on non-target organisms.This article reviews the toxicity of neonicotinoid insecticides to a variety of non-target organisms such as aquatic organisms,non-target insects,birds and mammals,as well as the influence of neonicotinoid insecticides on human health.These insecticides had acute lethal toxicity to all types of organisms,but the observed median lethal concentrations(LC50)or lethal dose(LD50)differed greatly among different species,with the order from low to high being insects(0.01~2.38 mg·L^-1,3.7~81 ng·bee^-1),crustaceans(0.59~37.75 mg·L^-1),fish(1.2~241 mg·L^-1),birds(15~>2000 mg·kg^-1)and mammals(82~>5000 mg·kg^-1).The sub-lethal toxicity of neonicotinoid insecticides to non-target organisms included reducing fecundity and growth rate,reducing activity,affecting nervous system,disturbing metabolic balance,damaging DNA,etc.Overall,imidacloprid had the highest toxicity,while dinotefuran and nitenpyram had the lowest toxicity.The order of toxicity of acetamiprid,thiacloprid,thiamethoxam and clothianidin varied with species.For aquatic organisms and non-target insects,thiacloprid and clothianidin had higher toxicity.For birds and mammals,acetamiprid had higher toxicity.Finally,based on the shortcomings of the existing researches,the future research directions are proposed,aiming to provide scientific basis for risk assessment and rational application of these insecticides.