聚苯乙烯微塑料长期暴露对海水青鳉(Oryzias melastig-ma)亲代生长、繁殖及子代发育的影响

Effects of Polystyrene Microplastics on Growth and Reproduction of Pa-rental Generation and Development of Filial Generation of Marine Meda-ka(Oryzias melastigma)after a Long-term Exposure

微塑料污染是近年来受到国际社会广泛关注的海洋环境问题之一,由微塑料造成的生态和人类健康风险不容小觑,但微塑料对鱼类的长期危害目前尚无定论。为评估微塑料颗粒对海洋鱼类的长期影响,选取塑料生产和环境中常见的聚苯乙烯(polystyrene,PS)为研究对象,对海水青鳉(Oryzias melastigma)60 dph(days post hatching,dph)幼鱼进行了为期50 d的长期暴露,系统研究PS暴露对海水青鳉亲代的生长、繁殖和子代胚胎发育等的影响。结果显示,在粒径为10μm、浓度为1×10^(4) particles·L^(-1)和1×10^(5) particles·L^(-1)暴露条件下,PS处理组亲代体长和体质量的改变与对照组相比无显著差异,PS暴露未显著影响亲代性成熟进程和受精过程;PS暴露未显著影响子代胚胎心率和孵化时间,但能显著降低子代孵化率,造成胚胎发育畸形。上述结果表明,PS长期暴露对亲代生长和繁殖未产生明显影响,但对子代的胚胎发育具有不利影响,研究结果为科学评估海洋微塑料污染的生态风险提供了重要参考。

Microplastic pollution is one of the marine environmental issues that have received widely concerns by the international society in recent years.The risks of ecology and human health caused by microplastics should not be underestimated.However,the long-term impacts of microplastics on fish are still inconclusive.This study select-ed polystyrene(PS,10μm)microplastics as reference toxicant which were commonly found in plastic productions and environments.An exposure duration of 50 d of PS microplastics was conducted for the 60 dph(days post hatching)juveniles of marine medaka(Oryzias melastigma)to evaluate the long-term effects of microplastics on marine fish.The effects of PS exposure on the growth and reproduction of parental generation and the embryonic development of offspring were systematically explored.The results showed that under the exposure concentrations of 1×10^(4) particles·L^(-1) and 1×10^(5) particles·L^(-1) of 10μm PS,the body length and body mass of parental fishes in exposure groups were not significantly different from those in the control group.In addition,parental maturation and fertilization process were not significantly affected by PS exposure either.Although polystyrene exposure did not significantly affect the heart rate and hatching time of offspring embryos,it could significantly reduce the hatch-ing rate of offspring and cause deformity of embryos.These results indicated that long-term exposure to polysty-rene microplastics had no significant influence on parental growth and reproduction,but affected embryo develop-ment instead.This study provided an important reference for scientific evaluation of the ecological risks of marine microplastic pollution.