Distinguishing realistic environmental risks of nanoplastics by investigating fate and toxicology in real-world scenarios

塑料垃圾对海洋环境的污染是过去50年来消费品中塑料生产和使用急剧增加的一个明显和不良的后果。在世界各地的海洋环境中都发现了塑料碎片，需要确定塑料垃圾的污染程度和后果，这已成为为政策提供信息的高度优先事项。纳米塑料(初级颗粒)是通过破碎较大的碎片(次级颗粒)制造出来的，用于产品或形状；然而，在释放到环境中后，它们的外观和性能似乎难以区分。纳米塑料的丰富性和持久性是人类对海洋环境造成的大规模长期和日益严重的变化，对此风险评估是一个紧迫的优先事项。纳米材料由于其尺寸而具有独特的性质，而且在生物体中存在意想不到的毒性，因为纳米塑料可能会通过细胞膜运输，并可能留在肠道内，干扰消化系统的过程。纳米材料毒理学的研究已经进行了十多年，但这些早期研究中的许多都没有提供环境科学家评估纳米材料对环境造成的风险所需的信息。该项目的重点是提供关键信息，以加强纳米塑料的环境风险评估，并以真实世界暴露情景为基础。特别是，我们将研究与天然海水中存在的微生物之间的相互作用，以形成纳米塑料的微生物凝聚体，以及这些微生物凝聚体如何具有不同的性质，从而与纳米塑料颗粒相比具有不同的环境影响。我们将调查有毒物质如何与微生物凝聚体联系在一起，影响纳米塑料在测试海洋环境(中间生态系统)中积累的位置，以及有毒物质是否被释放给鱼类。将考虑各种终点，研究纳米塑料在鱼类和海洋无脊椎动物摄入后的毒理学和影响，其设计将能够模拟纳米塑料的不同浓度和大小的影响。该项目(RealRiskNano)的结果将是为风险评估员提供急需的信息，以评估纳米塑料对海洋生态系统构成的现实风险。

Contamination of marine environments by plastic debris is a visually obvious and undesirable consequence of dramatic increases in production and use of plastics in consumer products over the last 50 years. Pieces of plastic have been found in marine environments worldwide and the need to establish levels of contamination and consequences of plastic debris has become a high priority to inform policy. Nanoplastics are manufactured (primary particles) for use in products or form by fragmentation of larger pieces (secondary particles); however, their appearance and properties appear to be indistinguishable after release to the environment. The abundance and persistence of nanoplastics presents a chronic and increasing human-induced change of marine environments on a massive scale for which assessment of risk is an urgent priority. Nanomaterials have unique properties because of their size and there is concern for unexpected toxicity in organisms because nanoplastics may be transported across cell membranes and may persist within the gut and interfere with processes of the digestive system. Investigations of nanomaterial toxicology have been conducted for over ten years, but many of these early studies do not provide the information needed for environmental scientists to assess the risks nanomaterials pose to the environment. This project is focused on providing critical information to enhance the environmental risk assessment of nanoplastics, and is based on real-world exposure scenarios. In particular, we will investigate interactions with microorganisms present in natural seawater on the formation of microorg-agglomerates of nanoplastics and how these microorg-agglomerates have different properties and therefore different environmental effects compared to nanoplastic particles. We will investigate how toxic substances associate with microorg-agglomerates and influence where nanoplastics accumulate within test marine environments (mesocosms) and whether the toxic substances are released to fish. Toxicology and effects of nanoplastics in fish and marine invertebrates after ingestion will be studied considering a variety of endpoints with a design that will enable effects to be modelled across concentrations and sizes of nanoplastics. The outcome of this project (RealRiskNano) will be to provide risk assessors with urgently needed information to evaluate the realistic risk that nanoplastics pose in marine ecosystems.