Dibutyl phthalate (DBP) is used to help make plastics soft and flexible. It is used in shower curtains, raincoats, food wraps, bowls, car interiors, vinyl fabrics, floor tiles, and other products. Animal studies have reported developmental and reproductive effects from oral exposure. Dibutyl phthalate (DBP) is classified as a substance toxic to reproduction. No information is available on the carcinogenic effects of dibutyl phthalate in humans or animals. Treatment with dibutyl phthalate enhanced Aryl Hydrocarbon Receptor mRNA expression, which was reflected by the increased AhR protein level. ERα, ERβ, and PPARγ antagonists stimulated DBP-induced caspase-3 and LDH activities. AhR is involved in DBP-induced apoptosis and neurotoxicity, while the ERs and PPARγ signaling pathways are impaired by the phthalate. In vitro test showed that DBP killed all Demodex mites within 1 hour. Dibutyl phthalate emulsion is promising to be developed as a safe, effective therapeutic medicament on demodicidosis.

Diethyl phthalate is a colourless liquid with a slight aromatic odour and low volatility. Diethyl phthalate is used as a plasticizer for cellulose ester plastic films and sheets (photographic, blister packaging, and tape applications) and moulded and extruded articles (consumer articles such as toothbrushes, automotive components, tool handles, and toys). Diethyl phthalate was reported as an ingredient in 67 cosmetic formulations. Diethyl phthalate is used as a component in insecticide sprays and mosquito repellents. Diethyl phthalate is likely to undergo biodegradation in the environment. General population exposure in the USA, as estimated from urinary concentrations of the monoester, was estimated to be 12 µg/kg body weight per day (median value). Dermally applied diethyl phthalate penetrates the skin and can be widely distributed in the body, but it does not accumulate in tissue. Diethyl phthalate has irritant effects on the eyes, skin, and mucous membranes and can lead to central nervous system (CNS) effects in exposed workers. The exposure to diethyl phthalates (DEP), a parent compound of the monoethyl phthalate (MEP) metabolite, may be associated with increased risk of BC (Odds Ratio of 2.20, p value for trend, p<0.003).

Dimethyl phthalate, an organic compound, is used as repellents. This compound is a pollutant that is very harmful to organisms due to its mutagenicity, teratogenicity and carcinogenicity. It was discovered, that dimethyl phthalate could alter the biological function of the one of the most important bacteria in the environment, P. fluorescens.