Esters of Aromatic Diacids (Phthalates)

Abstract Phthalate esters are used as plasticizers for a variety of plastic materials; those of C8 and above are used to add flexibility to polyvinyl chloride (PVC). They also are used with vinyl and cellulose resins to lend toughness and flexibility. They are commonly used in wire and cable coverings, moldings, vinyl consumer products, and medical devices. Some low‐molecular‐weight phthalate esters (e.g., methyl, ethyl, and butyl) are preferentially used as industrial solvents and in consumer products, such as ink and lacquer. Phthalates occur mainly in liquid form with high boiling ranges and very low vapor pressures, both contributing to the high stability of these materials. The critical health effects of phthalate esters like DEHP, butylbenzyl phthalate (BBP), di‐ iso ‐butyl phthalate (DIBP), di‐ n ‐butyl phthalate (DNBP), and dipentyl phthalate (DPP) are their interaction with the endogenous production of fetal testicular testosterone in rats. This impairs the reproduction of rodents by decreasing sperm production so that ECHA has labeled this group as toxic for reproduction (1B), whereas high molecular phthalates (HMP) such as DINP do not warrant classification for effects on sexual function, fertility, and developmental toxicity. Currently, di‐isononylphthalate (DINP) is replacing di(2‐ethylhexyl) phthalate (DEHP) widely in industrial and consumer products. Photodegradation half‐lives of dimethyl‐ and diethylphthalate are about 14 and 3 days, respectively, those of the other esters below 1 day. Half‐lives of aerobic degradation differ largely. The acute aquatic EC or LD50 values determined in algae, daphnids, and minnows mostly did not show effects at the solubility limits. Legal limits of European Commission (EC) for phthalates in plastic layer in direct contact with food are as follows: DBP up to 0.3 mg/kg, BBP, up to 30 mg/kg, DEHP, up to 1.5 mg/kg, sum of DINP and DIDP up to 9 mg/kg.