Ones That Get Away: Investigating the Leaching of Persistent, Mobile, and Toxic Plastic Additives from New and Environmentally Sampled Plastic Items

Plastic additives are substances used to aid in plastic manufacturing or to impart unique properties (e.g., colorants, plasticizers, etc.). However, some plastic additives are persistent, mobile, and toxic (PMT). PMT substances can pose a substantial risk to water quality, as their stability and low adsorption potential enable them to pass through water treatment processes and remain in the environment long after their release. Importantly, many additives can leach out of plastics during environmental weathering. Despite these known risks, there has yet to be any work studying PMT plastic additive release from different plastic items or how weathering may impact their leaching. Herein, PMT plastic additive leaching from store-bought and environmentally sampled plastic items was investigated. The leachates of 68 plastic items were analyzed by using high-performance liquid chromatography with quantitative time-of-flight mass spectrometry. Significantly higher (p = 0.05) numbers and levels of PMT substances were observed in the environmental samples when compared to store-bought. Furthermore, item categories such as toys and hardware supplies had higher numbers or levels of PMT substances than other items. These results discuss the role that weathering can play in PMT leaching and highlight items and compounds with high amounts or numbers of PMT substances, which can inform future monitoring.