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

塑料碎片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显而易见的不良后果。在世界各地的海洋环境中都发现了塑料碎片，确定塑料碎片的污染程度和后果的必要性已成为制定政策的高度优先事项。纳米塑料被制造（初级颗粒）用于产品或通过破碎较大的碎片（次级颗粒）形成;然而，它们的外观和特性在释放到环境中后似乎无法区分。纳米塑料的丰富性和持久性是人类引起的大规模海洋环境变化的一个长期和日益严重的问题，因此评估风险是一个紧迫的优先事项。纳米材料因其尺寸而具有独特的性质，并且人们担心生物体中的意外毒性，因为纳米塑料可能会穿过细胞膜运输，并可能在肠道内持续存在并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，但许多早期研究并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，并基于真实世界的暴露情景。特别是，我们将研究与天然海水中存在的微生物在纳米塑料微生物聚集体形成过程中的相互作用，以及这些微生物聚集体与纳米塑料颗粒相比如何具有不同的性质，从而产生不同的环境影响。我们将研究有毒物质如何与微生物团聚体相关联，并影响纳米塑料在测试海洋环境（中生态系统）中的积累，以及有毒物质是否会释放给鱼类。将研究摄入后纳米塑料在鱼类和海洋无脊椎动物中的毒理学和影响，考虑各种终点，设计将使纳米塑料的浓度和大小能够模拟影响。该项目（RealRiskNano）的成果将为风险评估人员提供急需的信息，以评估纳米塑料在海洋生态系统中构成的现实风险。

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.