Vyas Nimish B, Spann James W, Hulse Craig S, Borges Shannon L, Bennett Richard S, Torrez Martin, Williams Bruce I, Leffel Robert
U.S. Geological Survey, Patuxent Wildlife Research Center, Beltsville Lab, c/o BARC-East Building 308, 10300 Baltimore Avenue, Beltsville, Maryland 20705, USA.
Environ Toxicol Chem. 2006 Jul;25(7):1762-71. doi: 10.1897/05-230r.1.
We conducted two laboratory subacute dietary toxicity tests and one outdoor subacute dietary toxicity test to determine the effectiveness of the U.S. Environmental Protection Agency's deterministic risk assessment model for evaluating the potential of adverse effects to birds in the field. We tested technical-grade diazinon and its D.Z.N 50W (50% diazinon active ingredient wettable powder) formulation on Canada goose (Branta canadensis) goslings. Brain acetylcholinesterase activity was measured, and the feathers and skin, feet, and gastrointestinal contents were analyzed for diazinon residues. The dose-response curves showed that diazinon was significantly more toxic to goslings in the outdoor test than in the laboratory tests. The deterministic risk assessment method identified the potential for risk to birds in general, but the factors associated with extrapolating from the laboratory to the field, and from the laboratory test species to other species, resulted in the underestimation of risk to the goslings. The present study indicates that laboratory-based risk quotients should be interpreted with caution.
我们进行了两项实验室亚急性膳食毒性试验和一项室外亚急性膳食毒性试验，以确定美国环境保护局确定性风险评估模型在评估野外鸟类潜在不良影响方面的有效性。我们用技术级二嗪农及其D.Z.N 50W（50%二嗪农活性成分可湿性粉剂）制剂对加拿大鹅（Branta canadensis）雏鹅进行了测试。测量了脑乙酰胆碱酯酶活性，并分析了羽毛、皮肤、足部和胃肠道内容物中的二嗪农残留量。剂量反应曲线表明，在室外试验中二嗪农对雏鹅的毒性明显高于实验室试验。确定性风险评估方法确定了一般鸟类存在风险的可能性，但从实验室外推到野外以及从实验室试验物种外推到其他物种的相关因素导致对雏鹅风险的低估。本研究表明，基于实验室的风险商数应谨慎解读。
