School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.
Standards Development Branch, Ontario Ministry of the Environment and Climate Change, Toronto, Ontario, Canada.
Environ Toxicol Chem. 2018 May;37(5):1430-1445. doi: 10.1002/etc.4088. Epub 2018 Apr 11.
Neonicotinoids are a group of insecticides commonly used in agriculture. Due to their high water solubility, neonicotinoids can be transported to surface waters and have the potential to be toxic to aquatic life. The present study assessed and compared the acute (48- or 96-h) toxicity of 6 neonicotinoids (acetamiprid, clothianidin, dinotefuran, imidacloprid, thiacloprid, and thiamethoxam) to 21 laboratory-cultured and field-collected aquatic invertebrates spanning 10 aquatic arthropod orders. Test conditions mimicked species' habitat, with lentic taxa exposed under static conditions, and lotic taxa exposed under recirculating systems. Median lethal concentrations (LC50s) and median effect concentrations (EC50s; immobility) were calculated and used to construct separate lethal- and immobilization-derived species sensitivity distributions for each neonicotinoid, from which 5th percentile hazard concentrations (HC5s) were calculated. The results showed that the most sensitive invertebrates were insects from the orders Ephemeroptera (Neocloeon triangulifer) and Diptera (Chironomus dilutus), whereas cladocerans (Daphnia magna, Ceriodaphnia dubia) were the least sensitive. The HC5s were compared with neonicotinoid environmental concentrations from Ontario (Canada) monitoring studies. For all neonicotinoids except imidacloprid, the resulting hazard quotients indicated little to no hazard in terms of acute toxicity to aquatic communities in Ontario freshwater streams. For the neonicotinoid imidacloprid, a moderate hazard was found when only invertebrate immobilization, and not lethality, data were considered. Environ Toxicol Chem 2018;37:1430-1445. © 2018 SETAC.
新烟碱类杀虫剂是一类常用于农业的杀虫剂。由于其高水溶性，新烟碱类杀虫剂可能会被运移到地表水中，并有可能对水生生物产生毒性。本研究评估和比较了 6 种新烟碱类杀虫剂（乙酰甲胺磷、噻虫嗪、噻虫啉、吡虫啉、噻虫胺和噻虫砜）对 21 种实验室培养和野外采集的水生无脊椎动物的急性毒性（48 或 96 小时），这些无脊椎动物跨越了 10 个水生节肢动物目。测试条件模拟了物种的栖息地，其中静水生物类群在静态条件下暴露，流水生物类群在循环系统中暴露。计算了半数致死浓度（LC50）和半数效应浓度（EC50；不动性），并用于为每种新烟碱类杀虫剂分别构建基于致死效应和基于不动性效应的物种敏感性分布，从中计算出第 5 百分位数危害浓度（HC5）。结果表明，最敏感的无脊椎动物是蜉蝣目（Neocloeon triangulifer）和双翅目（Chironomus dilutus）的昆虫，而枝角类（Daphnia magna，Ceriodaphnia dubia）的敏感性最低。将 HC5 与安大略省（加拿大）监测研究中的新烟碱类环境浓度进行了比较。除了吡虫啉之外，对于所有其他新烟碱类杀虫剂，基于急性毒性的危害商表明，它们对安大略省淡水溪流中的水生群落没有危害或危害很小。对于新烟碱类杀虫剂吡虫啉，如果只考虑无脊椎动物的不动性而不考虑致死性数据，则发现存在中度危害。Environ Toxicol Chem 2018;37:1430-1445. © 2018 SETAC.
