聚苯乙烯微塑料暴露对稀有鮈鲫仔鱼生长的影响

微塑料已经成为一种新型的污染物,关于微塑料本身所造成毒性效应的研究较少。本研究以稀有鮈鲫Gobiocypris rarus初孵仔鱼为受试对象,研究了不同粒径(0.1μm、1μm、10μm)、不同浓度(0.055μg·L^-1、0.55μg·L^-1、5.5μg·L^-1、55μg·L^-1、550μg·L^-1)的聚苯乙烯(PS)微塑料对稀有鮈鲫仔鱼存活、生长的影响以及微塑料在仔鱼体内的累积和清除情况。暴露7 d后,各暴露组仔鱼的存活率和全长与空白对照组间的差异均无统计学意义(P>0.05);各暴露组仔鱼的鳃、消化道内均发现荧光微塑料,荧光强度随微塑料浓度增高而增强;经过7 d净化后,仔鱼体内PS微塑料均显著减少(P<0.05)。本研究表明,环境浓度水平的PS微塑料虽可在稀有鮈鲫体内积累,但清除速度也较快,在个体可观察水平上未见明显的毒性效应。

Effects of Polystyrene Microplastics Exposure on the Growth of Gobiocypris rarus Larvae

In recent years,the worldwide presence of microplastics has become a new type of contaminant However,the direct biological toxicity of microplastics still remains unclear.In this study,the effects of 3 sizes(0.1 μm,1 μm,and 10μm)of polystyrene(PS)microplastics at different concentrations(0.055μg·L^-1、0.55μg·L^-1、5.5μg·L^-1、55μg·L^-1、550μg·L^-1)on the survival and growth of rare minnow(Gobiocypris rarus)larvae were studied.Accumulation and removal of PS microplastics in the body were also detected.After exposing the larvae to PS microplastics for 7 days,no significant differences on the survival and total length of G.rarus were found between the treatment and control groups(P>0.05).Fluorescent plastic particles were observed in gill and digestive tract in the exposed larvae.The fluorescence intensity enhanced in the exposed larvae with the increase of PS microplastics concentration.Plastic particles were significantly reduced from exposed larvae after they were reared in the water with no microplastics(P<0.05).It is suggested that although PS microplastics can be accumulated in the body,the removal rate was fast,and the environment-relevant concentrations of PS microplastics have no observed toxic effect on G.rarus larvae.