University of Ljubljana, Faculty of Chemistry and Chemical Technology, 113 Večna pot, SI-1000, Ljubljana, Slovenia.
University of Ljubljana, Faculty of Chemistry and Chemical Technology, 113 Večna pot, SI-1000, Ljubljana, Slovenia.
Water Res. 2020 May 15;175:115644. doi: 10.1016/j.watres.2020.115644. Epub 2020 Feb 27.
Microplastics are very complex pollutants; they can be made of many polymer types and exist in various shapes and sizes. When they enter the environment they are affected by biotic and abiotic factors that cause their properties to change. In this context, the aim of our study was to evaluate the extent to which biofouling affects the properties and toxicity of microplastics. Cosmetic polyethylene microbeads were incubated in stream water for four weeks resulting in biofouling and aging. Subsequently, the changes in properties (sinking, particle size, adsorption, and leaching of model metal - silver) and the microplastics toxicity to daphnids Daphnia magna and duckweed Lemna minor were evaluated. Pristine microplastics did not affect daphnids but they significantly affected the root growth of duckweed. On the other hand, reference natural particles (beech sawdust) did not show any negative effects. We observed significant differences in the properties of aged versus pristine microplastics. When compared to pristine microplastics, aged microplastics adsorbed more silver and the subsequent leaching of silver was more intensive, especially in the medium with an acidic pH. Microplastics with adsorbed silver had a high ecotoxicological potential and at environmentally relevant concentrations affected both daphnids and duckweed. This study suggests that biofouling is an important parameter that affects microplastics properties, pollutant adsorption and release into the environment, and toxicity. Overall, there are significant alterations of the microplastics properties, behaviour, and fate in the environment.
微塑料是非常复杂的污染物；它们可以由多种聚合物类型制成，并以各种形状和大小存在。当它们进入环境时，会受到生物和非生物因素的影响，导致它们的性质发生变化。在这种情况下，我们研究的目的是评估生物污垢对微塑料性质和毒性的影响程度。将化妆品用聚乙烯微珠在溪流水中孵育四周，导致生物污垢和老化。随后，评估了性质的变化（沉降、粒径、吸附和模型金属-银的浸出）以及微塑料对大型溞 Daphnia magna 和浮萍 Lemna minor 的毒性。原始微塑料对大型溞没有影响，但对浮萍的根生长有显著影响。另一方面，参考天然颗粒（山毛榉木屑）没有显示出任何负面影响。我们观察到老化与原始微塑料之间的性质存在显著差异。与原始微塑料相比，老化微塑料吸附更多的银，随后银的浸出更加剧烈，尤其是在酸性 pH 值的介质中。吸附银的微塑料具有高生态毒性潜力，在环境相关浓度下会影响大型溞和浮萍。本研究表明，生物污垢是影响微塑料性质、污染物吸附和释放到环境中以及毒性的一个重要参数。总体而言，微塑料在环境中的性质、行为和命运发生了重大变化。
