摘要
为明确吡虫啉和氟硅唑在草莓上施用后可能产生的膳食暴露风险,进行了规范的田间残留试验及对不同人群的膳食风险评估。结果表明:保护地栽培条件下,吡虫啉、氟硅唑在草莓上的消解速率符合一级动力学方程,半衰期分别为6.3 d和9.9~11.5 d。10%吡虫啉可湿性粉剂(WP)分别按有效成分37.5和56.25 g/hm2剂量于草莓果实为成熟个体一半大小时开始施药,共施2~3次,每次间隔7 d,于末次施药后3、5、7、10 d时分别采样测定,草莓中吡虫啉的残留量在0.022~0.16 mg/kg之间;400 g/L的氟硅唑乳油(EC)分别按有效成分45和67.5 g/hm2剂量于草莓果实为成熟个体一半大小时开始施药,共施2~3次,每次间隔7 d,于末次施药后3、5、7、10 d时分别采样测定,氟硅唑在草莓中的残留量为0.079~0.30 mg/kg。基于此残留试验数据、各类食物的日平均膳食摄入量及每日允许摄入量(ADI),计算得到中国各类人群中吡虫啉和氟硅唑暴露的风险商(RQ)。结果表明:草莓中吡虫啉和氟硅唑的急性风险商(ARQ)分别为其急性参考剂量(ARf D)的0.18%~1.0%和10%~37.7%,不存在不可接受的急性膳食暴露风险;草莓中吡虫啉和氟硅唑的慢性风险商(CRQ)分别为其ADI值的18.6%~85.3%和68.3%~316.4%,其中氟硅唑对2~4岁幼童的暴露风险超过100%,存在明显风险,但草莓中的氟硅唑对其全膳食暴露风险的贡献率不超过3.2%,并非其主要风险源;两种农药对其他暴露人群均不存在明显膳食风险。中国尚未制定草莓中吡虫啉和氟硅唑的最大残留限量(MRL)值,本研究推荐的吡虫啉和氟硅唑的MRL值对消费者长期慢性暴露风险的保护水平(CPLc)分别为18~109倍和2~13倍,短期急性暴露风险的保护水平(CPLa)分别为121~725倍及6~36倍,对消费者的保护水平均较高。建议:草莓中吡虫啉和氟硅唑的MRL值均可定为0.5 mg/kg,安全间隔期可分别为3 d和5 d;但对于2~4岁幼童,应充分关注氟硅唑对其的慢性膳食暴露风险。
In order to assess the dietary exposure risk of imidacloprid and flusilazole residue in greenhouse strawberry, the final residues and decline trends of imidacloprid and flusilazole used in strawberry were studied. The dietary exposure and risk assessment were conducted based on the supervised field trial data. The results showed that the decline dynamics of imidacloprid and flusilazole accorded with the first-order kinetics in greenhouse conditions with imidacloprid applied at a dosage of56.25 g(a.i)/hm2 and flusilazole at a dosage of 67.5 g(a.i)/hm2. The half-lives of imidacloprid and flusilazole were 6.3 d and 9.9-11.5 d, respectively. The strawberry was sprayed in 2-3 times at an interval of 7 d with imidacloprid 10% wettable powder at dosage of 37.5 g(a.i)/hm2 and 56.25 g(a.i)/hm2 at the stage of half ripe fruit. At 3, 5, 7, 10 days after the last application, the final residue levels of imidacloprid in greenhouse strawberry at harvesting were 0.022-0.16 mg/kg. The strawberry was sprayed in 2-3 times at an interval of 7 d with flusilazole 400 g/L emulsifiable concentrate at dosage of45 g(a.i)/hm2 and 67.5 g(a.i)/hm2. At 3, 5, 7, 10 days after the last application, the final residue levels of flusilazole in greenhouse strawberry at harvesting were 0.079-0.30 mg/kg. Chronic and acute risk quotient of imidacloprid and flusilazole were calculated from residue trial data, average dietary intake in all kinds of food and their acceptable daily intake. The results showed that acute risk quotient of imidacloprid and flusilazole in strawberry were about 0.18%-1.01% and 10%-37.7% of their acute reference doses, respectively, indicating that the acute dietary exposure risks of these two pesticides are acceptable. The chronic risk quotient of imidacloprid and flusilazole in strawberry is about 18.6%-85.3% and 68.3%-316.4% of their acceptable daily intakes, respectively. Chronic risk quotient of flusilazole in strawberry for children between 2 and 4 years is about 284.9%-316.4%, indicating chronic risk of flusilazole in baby foods. As exposure risks by strawberry devoted less than 3.2% of the total dietary risks, dietary risk of flusilazole in strawberry may be not the main portion of the whole food dietary. Up to now, no maximum residue limits of imidacloprid and flusilazole in strawberry were set in China. Further, assessments of consumer protection level were carried out based on field trial residues.The results showed that consumer protection levels are acceptable with CPLc of imidacloprid and flusilazole at 18-109, 2-13 and CPLa at 121-725, 6-36. Maximum residue limits at 0.5 mg/kg and PHIs at 3 d, 5 d were recommended for imidacloprid and flusilazole in strawberry, respectively. For 2-4 years old children, the risk of chronic dietary exposure for flusilazole in strawberry could not be ignored.
出处
《农药学学报》
CAS
CSCD
北大核心
2016年第2期232-240,共9页
Chinese Journal of Pesticide Science
基金
上海市农委科技攻关项目(沪农科攻字(2013)第3-2号)
关键词
草莓
吡虫啉
氟硅唑
农药残留
膳食暴露
风险评估
strawberry
imidacloprid
flusilazole
pesticide residues
dietary exposure
risk assessment