微塑料与磷酸三(1,3-二氯-2-丙基)酯联合暴露对子代斑马鱼甲状腺功能的影响

Effects of combined exposure of microplastics andtris(1,3-dichloro-2-propyl)phosphate on thyroid function of offspring zebrafish

鉴于微塑料与其他污染物共存会改变共存物的生物利用性及毒性,大量应用的阻燃剂磷酸三(1,3-二氯-2-丙基)酯(TDCIPP)与聚苯乙烯纳米塑料(PS-NPs)在水环境中共存性极高,共存物可能对人类健康带来不可预知的风险.本文以毒理学的模式生物斑马鱼为受试生物,采用全生命周期暴露的方式,将受精2 h的胚胎暴露于4、20、100μg/L TDCIPP暴露组、20 mg/L PS-NPs暴露组以及4μg/L TDCIPP+20 mg/L PS-NPs、20μg/L TDCIPP+20 mg/L PS-NPs以及100μg/L TDCIPP+20 mg/L PS-NPs复合暴露组中,暴露时间持续150 d.暴露结束后,分析母代与子代的甲状腺激素以及与下丘脑-垂体-甲状腺轴(HPT轴)功能基因的表达.结果显示,NPs能够增强TDCIPP在生物体内的积累,并诱发子代形态学异常.同时,PS-NPs共存能显著加剧TDICPP对子代甲状腺激素的干扰,显著加剧TDCIPP甲状腺干扰的母体传递效应且F1代14 d是甲状腺激素作用的敏感时间节点.

In view of the fact that coexistence of microplastics with other pollutants can change the bioavailability and toxicity of co-existing substances,the heavily used flame retardants tri-(1,3-dichloro-2-propyl)phosphate(TDCIPP)and polystyrene nanoplastics(PS-NPs)are highly co-existing in water environments,and co-existing substances may pose unpredictable risks to human health.In this study,zebrafish,a model organism of toxicology,was exposed to the whole life cycle.Embryos at 2 h of fertilization were exposed to 4,20,100μg/L TDCIPP exposure groups,20 mg/L PS-NPs exposure groups,and 4μg/L TDCIPP+20 mg/L PS-NPs,20μg/L TDCIPP+20 mg/L in PS-NPs and 100μg/L TDCIPP+20 mg/L PS-NPs combined exposure group,the exposure lasted for 150 days.After exposure,maternal and progeny thyroid hormone expression and gene expression related to hypothalamic-pituitary-thyroid axis(HPT axis)function were analyzed.The results showed that NPs could enhance the accumulation of TDCIPP in vivo and induce morphological abnormalities in offspring.At the same time,the coexistence of PS-NPs could significantly aggravate the interference of TDICPP on the progeny thyroid hormone,significantly aggravate the maternal transmission effect of TDCIPP thyroid interference,and F1 generation 14 d is the sensitive time node of thyroid hormone action.