Hamilton Bonnie M, Jantunen Liisa M, Rochman Chelsea M
Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada.
Air Quality Processes Research Section, Environment and Climate Change Canada, Egbert, ON, Canada.
Environ Toxicol Chem. 2025 Feb 1;44(2):460-469. doi: 10.1093/etojnl/vgae040.
Microplastics (< 5 mm) are a diverse class of contaminants ranging in morphology, polymer type, and chemical cocktail. Microplastic toxicity can be driven by one or a combination of these characteristics. Most studies, however, evaluate the physical effect of the most commercially available polymers. By disregarding other polymers with high consumption and/or production rates, and the chemical constituents of plastics, we fail to have a holistic understanding of the mechanisms of toxicity. Polyurethane is understudied in terms of effects testing yet considered one of the most hazardous polymers due to its chemical composition. Polyurethane is a high production polymer and is found in common consumer products ranging from packaging to spray foam insulation. To better understand the physico-chemical effects of polyurethane and a common additive in polyurethane products, we exposed larval fathead minnows for 28 days to polyurethane without chemical additives (i.e., plastic treatment), chemical leachate from polyurethane containing chemical additives (i.e., tris(chloropropyl)phosphate [TCPP]; i.e., chemical treatment) and polyurethane with chemical additives (i.e., plastic with chemical treatment) in a fully factorial experiment. We observed significant decreases in growth at 12 days posthatch (dph) in the plastic, chemical, and plastic with chemical treatments, suggesting a physical and chemical driver of toxicity. At 28 dph, we did not observe significant differences in growth, suggesting individuals can recover. We also observed concentrations of ΣTCPPs in fathead minnow exposed to the plastic with chemical treatment and the chemical only treatment, demonstrating TCPP uptake in exposed individuals. Combined, our data suggests the importance of both the physical and chemical components of microplastics when assessing effects, and thus emphasizing the need to evaluate the effects of microplastics in a multidimensional way.
微塑料（<5毫米）是一类形态、聚合物类型和化学混合物各不相同的污染物。微塑料的毒性可能由这些特性中的一种或多种共同驱动。然而，大多数研究评估的是最常见商业聚合物的物理效应。由于忽视了其他高消费率和/或高生产率的聚合物以及塑料的化学成分，我们无法全面了解毒性机制。聚氨酯在效应测试方面研究较少，但由于其化学成分，被认为是最危险的聚合物之一。聚氨酯是一种高产量聚合物，常见于从包装到喷雾泡沫绝缘材料等各种消费品中。为了更好地了解聚氨酯及其制品中一种常见添加剂的物理化学效应，我们在一项全因子实验中，将黑头呆鱼幼体暴露于不含化学添加剂的聚氨酯（即塑料处理）、含化学添加剂的聚氨酯的化学渗滤液（即磷酸三（氯丙基）酯[TCPP]；即化学处理）以及含化学添加剂的聚氨酯（即含化学处理的塑料）中28天。我们观察到，在孵化后12天（dph），塑料处理组、化学处理组和含化学处理的塑料组的生长显著下降，这表明存在物理和化学毒性驱动因素。在28 dph时，我们没有观察到生长方面的显著差异，这表明个体可以恢复。我们还观察到，暴露于含化学处理的塑料和仅化学处理的黑头呆鱼体内的ΣTCPPs浓度，证明暴露个体吸收了TCPP。综合来看，我们的数据表明，在评估效应时，微塑料的物理和化学成分都很重要，因此强调需要以多维方式评估微塑料的效应。
