八种新烟碱类杀虫剂对地熊蜂工蜂的毒性及风险评估

【目的】评价新烟碱类杀虫剂对地熊蜂Bombus terrestris工蜂的毒性和生态风险性,为温室施用新烟碱类杀虫剂提供科学依据。【方法】分别采用饲喂法和接触法测定了噻虫嗪、噻虫胺、啶虫脒、吡虫啉、烯啶虫胺、呋虫胺、噻虫啉和氟吡呋喃酮8种新烟碱类杀虫剂对地熊蜂成年工蜂的急性经口和急性接触毒性。同时评估了8种新烟碱类杀虫剂对地熊蜂工蜂的生态风险性。【结果】8种杀虫剂经饲喂法测定,噻虫胺对地熊蜂成年工蜂的毒性最高,24 h和48 h的LD 50值分别为0.0433和0.0330μg a.i./蜂;氟吡呋喃酮毒性最低,24 h和48 h的LD 50值分别为72.4119和67.9079μg a.i./蜂。接触法测定的毒性与饲喂法测得的结果一致,噻虫胺的毒性最高,24 h和48 h的LD 50值分别为0.0220和0.0192μg a.i./蜂;氟吡呋喃酮的毒性最低,24 h和48 h的LD 50值分别为141.7641和130.3062μg a.i./蜂。生态风险评估表明,啶虫脒、噻虫啉和氟吡呋喃酮对地熊蜂成年工蜂的经口毒性和接触毒性均表现为低风险,吡虫啉、烯啶虫胺和呋虫胺的毒性表现为中等风险。噻虫嗪和噻虫胺对地熊蜂成年工蜂的经口毒性表现为中等风险,而接触毒性则表现为高风险。【结论】检测的8种新烟碱类杀虫剂中啶虫脒、噻虫啉与氟吡呋喃酮对地熊蜂成年工蜂的毒性为低毒,而噻虫嗪、噻虫胺、吡虫啉、烯啶虫胺、呋虫胺这5种杀虫剂均为高毒。在设施蔬菜花期使用地熊蜂授粉时,建议禁用这5种中、高风险的新烟碱类杀虫剂,以避免对熊蜂授粉的危害,而另3种低风险药剂可根据田间试验情况合理施用。

Toxicity and risk assessment of eight neonicotinoid insecticides to workers ofBombusterrestris(Hymenoptera: Apoidea)

【Aim】 This study aims to evaluate the toxicity and ecological risk ofneonicotinoid insecticides to Bombus terrestris workers so as to provide a scientific basisfor application of neonicotinoid insecticides in greenhouse. 【Methods】 The acute oral and contact toxicities of eight neonicotinoid insecticides, including thiamethoxam,clothianidin, acetamiprid, imidacloprid, nitenpyram, dinotefuran, thiacloprid, andflupyradifurone, to adult workers of B. terrestris were tested by feeding and contact methods, respectively, and the ecological risk of these neonicotinoid insecticides to B.terrestris was assessed. 【Results】 Clothianidin showed the highest toxicity to adultworkers of B. terrestris by acute oral exposure, with the LD₅₀ values of 0.0433 and 0.0330μg a.i./bee at 24 and 48 h after exposure, respectively, while fluorofuranone showed thelowest toxicity, with the LD₅₀ values of 72.4119 and 67.9079 μg a.i./bee at 24 and 48 hafter exposure, respectively. The toxicities of the eight insecticides determined by acutecontact were similar to those determined by acute oral exposure. Clothianidin showed thehighest acute contact toxicity to adult workers of B. terrestris, with the LD₅₀ values of0.0220 and 0.0192 μg a.i./bee at 24 and 48 h after acute contact, respectively, whilefluorofuranone showed the lowest toxicity, with the LD₅₀ values of 141.7641 and 130.3062 μg a.i./bee at 24 and 48 h after acute contact, respectively. Ecological risk assessmentrevealed that acetamiprid, thiacloprid and flupirfenone showed low risk to adult workers ofB. terrestris, while imidacloprid, nitenpyram and dinotefuran showed moderate risk.Thiamethoxam and clothianidin showed moderate risk to adult workers of B. terrestris inoral toxicity, while high risk in contact toxicity. 【Conclusion】 Among the eightneonicotinoid insecticides tested, acetamiprid, thiacloprid, and flupirfenone show lowtoxicity to adult workers of B. terrestris, while the other five neonicotinoid insecticides (thiamethoxam, clothianidin, imidacloprid, nitenpyram and dinotefuran) show high toxicity.We recommend that the five neonicotinoid insecticides with high and moderate risk should bebanned in order to avoid exposing bumblebees to insecticide risk, while the other threeinsecticides with low risk might be considered for application in the field.