Dimethyl phthalate: uses and toxicity

Description

Dimethyl Phthalate is a colorless, oily liquid or solid with a slightly sweet odor. It is used as a plasticizer and solvent. This compound can be prepared by heating phthalic anhydride and methanol under reflux, together with a catalyst such as sulphuric acid or sodium bisulfate, for a period of time sufficient to bring the reactants to equilibrium.

Uses

Internationally, Dimethyl phthalate (DMP) is used in cosmetics as a fragrance ingredient, in hair sprays, hair conditioners, face powders and foundations, bath soaps and detergents, deodorants, and aftershave lotions. Non-cosmetic uses include solvents and plasticisers for nitrocellulose, cellulose acetate and cellulose acetate-butyrate compositions. DMP is used in explosives, printing inks, paper coatings, and adhesives, and as a fabric treatment. DMP is also used in insecticides and insect repellents.

In Australia, DMP is imported as finished products or mixtures and a raw chemical for local manufacture. DMP is used industrially in automotive parts, encapsulation of electrical wiring, mining, and construction, and fabrication of fiberglass, paints, nitrocellulose, cellulose acetates, and rubber. Downstream products include adhesives, putty hardeners, paints and coatings, plastic articles, children’s toys, and fragrance bases for household cleaning and cosmetic products. DMP is also used by various institutions and laboratories for biotechnological and pharmaceutical research.

Toxicity

Dimethyl phthalate (DMP) is the low molecular weight phthalate ester used in plastic products to increase flexibility, pellucidity, resilience, and longevity. Phthalates persist in the environment with a half-life of ≈ 20 years, and aqueous hydrolysis half-lives for DMP are 3.2 years. DMP is known to be a subchronic toxicant and an endocrine-disrupting chemical (EDC) that affects both male and female reproductive systems. Also, it is a teratogen, hampering the development of the fetus. Hence, wastewater-containing DMP must be treated before being discharged into the environment[1].

References

[1] Sangram Shamrao Patil, Hara Mohan Jena. “Process optimization and kinetic study of biodegradation of dimethyl phthalate by KS2, a novel strain of Micrococcus sp.” Scientific Reports 13 1 (2023): 3900.