phthalate

Phthalates are esters derived from phthalic acid (benzene-1,2-dicarboxylic acid). They are primarily used as plasticizers—substances added to plastics to impart flexibility and durability. Most phthalates are diesters formed from two alcohol groups; common examples include di(2-ethylhexyl) phthalate (DEHP, also known as DOP), diisononyl phthalate (DINP), diisodecyl phthalate (DIDP), and diethyl phthalate (DEP). Their production involves esterification of phthalic anhydride or phthalic acid with suitable alcohols.

Phthalates are widely used to soften polyvinyl chloride (PVC) in a range of products, including flooring and flooring underlayment, cables and tubing, vinyl coatings, adhesives, sealants, and various consumer goods. They are also found in some cosmetics, fragrances, and medical devices where flexibility and workability of plastics are required.

Exposure to phthalates occurs mainly through ingestion, inhalation, and dermal contact, with metabolism in the body typically converting them to monoesters and other metabolites that are excreted in urine. Several phthalates have been associated with adverse developmental and reproductive effects in animal studies, and some human data suggest potential health risks, though findings vary by compound and exposure level. As a result, regulatory actions in many regions restrict certain phthalates in toys, childcare articles, and other consumer products, and substitutions with alternative plasticizers have increased.

Environmentally, phthalates can leach from consumer products during use and at end of life. They are found in air, water, and sediments in some settings, though their persistence and ecological effects depend on the specific compound and conditions.