Plastics are ubiquitous contaminants that leak into the environment from multiple pathways including the use of treated sewage sludge (biosolids). Seven common plastics (polymers) were quantified in the solid fraction of archived biosolids samples from Australia and the United Kingdom from between 1950 and 2016. Six plastics were detected, with increasing concentrations observed over time for each plastic. Biosolids plastic concentrations correlated with plastic production estimates, implying a potential link between plastics production, consumption and leakage into the environment. Prior to the 1990s, the leakage of plastics into biosolids was limited except for polystyrene. Increased leakage was observed from the 1990s onwards; potentially driven by increased consumption of polyethylene, polyethylene terephthalate and polyvinyl chloride. We show that looking back in time along specific plastic pollution pathways may help unravel the potential sources of plastics leakage into the environment and provide quantitative evidence to support the development of source control interventions or regulations.

塑料是无处不在的污染物，可通过多种途径泄漏到环境中，包括使用经过处理的污水污泥（生物固体）。从 1950 年到 2016 年，在澳大利亚和英国存档的生物固体样品的固体部分中量化了七种常见塑料（聚合物）。检测到六种塑料，随着时间的推移观察到每种塑料的浓度增加。生物固体塑料浓度与塑料生产估计相关，这意味着塑料生产、消费和泄漏到环境中之间存在潜在联系。在 1990 年代之前，除聚苯乙烯外，塑料泄漏到生物固体中是有限的。从 1990 年代开始，观察到泄漏增加；可能受到聚乙烯、聚对苯二甲酸乙二醇酯和聚氯乙烯消费量增加的推动。