Objective To evaluate the combined subchronic toxicity of bisphenol A(BPA) and dibutyl phthalate(DBP) in male Sprague Dawley(SD) rats.Methods Forty 4‐week‐old male rats weighing 115‐125 g were randomly divided into BPA‐treated,DBP‐treated group,BPA+DBP‐treated and control groups and fed with a soy‐ and alfalfa‐free diet containing 285.4 ppm BPA,285.4 ppm DBP,285.4 ppm BPA plus 285.4 ppm DBP,and a control diet,respectively,for 90 consecutive days.At the end of the study,the animals were sacrificed by exsanguination via the carotid artery under diethyl etherane aesthesia and weighed.Organs,including liver,kidneys,spleen,thymus,heart,brain,and testis underwent pathological examination.The androgen receptor(AR),gonadotropin‐releasing hormone receptor(GNRHR),and progesterone hormone receptor(PR) genes from the hypothalamus were detected by real‐time PCR.The biomedical parameters were analyzed.Results No significant difference was found in food intake,body weight,tissue weight,organ/brain weight ratio,and biomedical parameters among the four groups(P>0.05).However,BPA and DBP up‐regulated AR,PR and GNRHR expression levels in rats and showed a synergistic or an additive effect in the BPA+DBP group.Conclusion The combined subchronic toxicity of BPA and DBP is synergistic or additive in male SD rats.
【目的】研究噻虫嗪在甘蔗和土壤中的残留及消解动态,并评价噻虫嗪残留对消费者的健康风险和土壤中非靶标生物蚯蚓的环境风险,为噻虫嗪在甘蔗上的安全使用提供科学依据。【方法】分别于2015和2016年在海南和广西开展10%噻虫嗪颗粒剂在甘蔗和土壤中的残留消解试验和最终残留试验,并根据蔗茎和土壤中噻虫嗪及其代谢物噻虫胺的残留量,评估其对人类急慢性膳食暴露风险和对非靶标生物蚯蚓的环境风险。【结果】噻虫嗪在甘蔗植株中的半衰期为8.4～18.2 d,在土壤中的半衰期为17.3～22.4 d;甘蔗蔗梢和蔗茎中噻虫嗪及其代谢物噻虫胺的最终残留量均低于定量限(LOQ)(0.05 mg/kg),但施用高剂量562.5 g a.i/ha后,收获期土壤中噻虫嗪残留量高于LOQ,达0.146～0.153 mg/kg;噻虫嗪和噻虫胺对我国一般人群的估计每日摄入量(EDI)仅为每日允许摄入量(ADI)的0.0039%～0.0049%,估计短期摄入量(ESTI)仅为急性参考剂量(ARfD)的0.17%～0.29%;噻虫嗪对蚯蚓的风险商(RQ)<0.01,噻虫胺对蚯蚓的RQ=0.016。【结论】在甘蔗苗期按照375.0～562.5 g a.i/ha沟施10%噻虫嗪颗粒剂1～2次,甘蔗中噻虫嗪和噻虫胺的最终残留量低于我国和国际食品法典委员会(CAC)的最大残留限量(MRL)标准,且该残留对人类健康的急慢性暴露风险在可接受范围之内;但建议该产品在甘蔗上登记使用时注意其代谢物噻虫胺对土壤非靶标生物蚯蚓的环境风险。
