人工合成纳米颗粒在水生食物链中的分布、传递及其影响因素

Distribution and trophic transfer of engineered nanoparticles along aquatic food chains and related influencing factors: A review

纳米技术作为一种最具有市场应用潜力的新兴科学技术,近十年来在基础理论和应用研究等方面迅猛发展,使其在化工、医疗、电子、能源、环境保护等行业得到了广泛的应用.人工合成纳米颗粒(engineered nanoparticles,ENPs)在纳米产品的整个生命周期中将不可避免地进入水环境,与水生生物直接或间接(营养传递)的接触,从而沿水生食物链进行传递和转移,并影响生物的一系列生命活动.本文以不同水生生物为对象,总结了ENPs在不同类群的生物中的分布特点,着重探讨了ENPs在淡水和海洋食物链中的传递规律,并分析了ENPs性质和水环境因素对传递过程的影响.本文最后对ENPs在水生食物链中的研究现状、前景和面临的挑战进行了分析和展望.

Nanotechnology is developing rapidly and has been widely applied in chemical engineering,electronic engineering,energy sources,environmental protection and other fields.Engineered nanoparticles（ENPs）are inevitably releasing into the aquatic environment during the entire life cycle of nano-products,thus exposing to aquatic organisms,which has been well investigated in the past decade.ENPs could be internalized by different types of aquatic organisms including algae,plants,and fish.Therefore,the possible transfer of ENPs between different aquatic organisms has attracted attentions,and many important publications reported the trophic transfer of ENPs through aquatic food chains.This review first provided the internalization and distribution of ENPs in different aquatic organisms including microorganism,aquatic plants,invertebrate and fish：（1）For microorganisms,ENPs are mainly adsorbed on the cellular surface,and then be internalized,and the internalization could lead to subsequent toxicity;（2）ENPs could be taken up by the roots of aquatic plants,and then be migrated to stem and leaves by evapotranspiration;（3）ENPs were mainly located in the hepatopancreas and gut of invertebrates;（4）ENPs could be accumulated in the gill and digestive tract of fish,and then distributed into other tissues such as liver and spleen.Secondly,the research status of ENPs in aquatic food chain were summarized and analyzed.The transfer of ENPs was observed in both freshwater and marine food chains,and current investigations on freshwater food chains contributed a larger proportion than in the marine.Most of the researches proved that ENPs can transfer along the food chain,but the biomagnification was only reported in a few publications.Thirdly,the influence of water chemistry factors and ENPs properties on the transfer of ENPs via aquatic food chains was discussed.For the water chemistry factors,like light illumination,solution pH,co-existing compounds such as natural organic matter,ionic strength,and oxidation–reduction potential all altered the bioavailability of ENPs and played important roles in the trophic transfer of ENPs.For the properties of ENPs,it is observed that：（1）the metal ions which were released from metal-containing ENPs can improve the bioavailability of ENPs in aquatic organisms;（2）different coatings of ENPs brought different or opposite surface charge on the surface,thus changing the internalization and bioavailability of ENPs.For example,ENPs with positively charged surface could be easily adsorbed on the surface of aquatic organisms than the negatively charged particles;（3）different size and shape influenced the contacting area between the ENPs and organisms,and ENPs with smaller size were usually more readily enter aquatic organisms,which were deeply discussed in this review.Finally,the current researches,prospects and challenges on ENPs transfer in the aquatic food chains are addressed.