Human Risk Assessment of Endocrine-Disrupting Chemicals Derived from Plastic Food Containers

In the manufacture of plastic containers, various materials such as additives (for example, plasticizers, stabilizers, antioxidants), polymers (for example, polystyrene [PS], polycarbonate [PC], polyvinyl chloride [PVC]) are widely used. Endocrine disrupting chemicals [EDCs] can migrate as residual monomers (for example, styrene for PS or bisphenol A [BPA] for PC) presented in polymers, as additives (for example, phthalates for PVC) used in polymer manufacturing, and/or as contaminants from the polymers depending on physicochemical conditions such as temperature, UV light, pH, microwave, and mechanical stress. Some phthalates (for example, DEHP, DBP), styrene, or bisphenol have been suspected to have endocrine disrupting effects, but human toxicological effects of these compounds are very controversial. For these reasons, a comprehensive review on toxicological and risk assessment studies for these chemicals (phthalates, BPA, and styrene) was carried out to evaluate their safety in humans. On the basis of exposure estimates for the these chemicals and reference doses (RfDs), we calculated hazard index (HI = chronic daily intake/tolerable daily intake [TDI] or RfD). A HI of less than 1 suggests an exposure lower than the safety limit of the chemicals. We showed that the HI values of these chemicals were lower then 1, but there are one or several exceptions for di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), di-isodecyl phthalate (DIDP), and di-n-octyl phthalate (DnOP; for example, exposure via infant formula, packaged lunch, total exposure), where estimated their HI values are higher than 1, which suggests an exposure higher than the safety limits of the chemicals. However, the HI of BPA was 0.0010.26 (3.571000 times lower than its safety limit), and the HI for styrene was 0.276 (3.62 times lower than its safety limit). In this article, we focused on recent issues concerning the endocrine-disrupting chemicals (EDCs) derived from plastic food containers or packaging. This review suggests that the use of plastic food containers might not exceed human safe limits n general with respect to endocrine disruptors aside from the exceptions of the phthalates mentioned earlier.