Quantification of phthalates, non-phthalate plasticizers, and organophosphates in recycled plastic pellets

As the global community advances toward a circular economy, the increased use of recycled plastics is becoming imperative. However, measures to manage chemical safety in this regard remain insufficient. In this study, we quantified phthalates, alternative plasticizers, and organophosphates in recycled plastic pellets primarily composed of polyethylene and polypropylene via gas chromatography-mass spectrometry while also assessing their associated risks via dermal exposure. The analysis of 44 pellet samples identified di(2-ethylhexyl) phthalate (DEHP; detected in 75% of samples, <0.1-55 μg/g), diisononyl phthalate (DiNP; 20%, <0.01-33 μg/g), diisononyl adipate (DiNA; 41%, <0.01-180 μg/g), tributyl acetyl citrate (ATBC; 75%, <0.02-61 μg/g), and di(2-ethylhexyl) terephthalate (DEHT; 86%, <0.01-9.8 μg/g), along with organophosphates such as tris (2-chloroethyl) phosphate (TCEP; 39%, <0.002-4.2 μg/g) and tris (1-chloro-2-propyl) phosphate (TCPP; 68%, <0.02-0.69 μg/g) as the major additives in the analyzed samples. The concentrations of ATBC and DiNA, which are authorized for food contact applications, were significantly higher in pellets originated from post-consumer containers/packaging. TXIB, TCEP, and TBEP were more abundant in pellets originated from plastic bottle caps and production scrap, which could be owing to the migration during manufacturing or handling. Initial risk assessment showed very low risks via dermal exposure for these chemicals in recycled plastic, although the findings are subject to limitations related to sample size and model assumptions. SYNOPSIS: Additives in recycled PP and PE plastics exists at low concentrations and pose low dermal exposure risks. Thus, recycled plastics could be safe for use in advancing a circular economy.