Influence of Air, Water, Light, and Salinity on Release of Plasticizers, Flame Retardants, and Ultraviolet Absorbents from Polystyrene Plastic.

Abstract

This study investigated how air, water, light, and salinity influence the release of three additives-phthalic acid esters (PAEs), organophosphate esters (OPEs), and organic ultraviolet absorbents (OUVAs)-from expanded polystyrene plastic (EPS). GC-MS/MS was used to quantify the concentrations of the three additives. The release kinetics and mechanisms under different conditions and the effects of various factors were analyzed. The release of PAEs and OPEs was more consistent with the first-order kinetics, while the release fitting of OUVAs was more in line with the second-order kinetics. Among all conditions, air exposure led to the highest release rates of PAEs (∑₁₆PAEs: k = 0.868 ng/g·day) and OPEs (∑₁₁OPEs: k = 0.927 ng/g·day). Compared to freshwater, seawater moderately inhibited EPS aging and additive release due to ion effects. Light significantly influenced both the rate and amount of additive release. Finally, the global release of plastic additives from EPS waste was estimated at 33.5k tons for PAEs, 646 tons for OPEs, and 420 tons for OUVAs.