Benzyl butyl phthalate is used as a plasticizer for polyvinyl chloride in vinyl floor tiles, vinyl foam and carpet backing, in cellulosic resins, and as an organic intermediate. It has also been used as a solvent and fixative in perfume. It is a colorless and odorless organic chemical. Exposure to benzyl butyl phthalate occurs during its production and use as a plasticizer, mainly in polyvinyl chloride products. It has been detected at low levels in indoor air, water, and a few foods. Benzyl butyl phthalate is classified as a substance toxic to reproduction. It demonstrated estrogen and anti-androgen activity. Prenatal exposure to phthalates could lead to smaller penis size and incomplete descent of testicles in baby boys.

Diethylhexyl phthalate (Di-2-ethylhexyl phthalate, DEHP), the most frequently occurring plasticiser in medical equipment manufactured from polymers of vinyl chloride, forms about 40% w/w of tubes and containers used for storing blood and for haemodialysis. The plasticiser leaches out into liquids with lipid contents, although it is very sparingly soluble in purely aqueous solutions. On infusion of 2-3 1 of stored blood, up to 200 mg DEHP may be transferred to the patient, while much higher quantities may be given during dialysis, which is moreover often repeated frequently over long periods. The acute toxicity of DEHP is very low (greater than 20 g/kg as LD50 in rats), and the ester is rapidly metabolised to products which are excreted in the urine and bile; chronic toxicity from the levels of dosage obtaining is thus very improbable. Carcenogenicity has never been demonstrable in animals, while teratological effects are of a very low order. The uses of DEHP fall into two major categories: polymer uses (e.g. consumer products such as footwear, shower curtains and toys, medical devices and commercial/industrial uses) and non-polymer uses (e.g. dielectric fluids, paints, adhesives and inks). Non-polymer uses represent less than 5% of the total DEHP used in the USA. Approximately 45% of total consumption of DEHP in the USA is for plasticizing various industrial and commercial products. Industrial and commercial uses of DEHP include resilient flooring, wall covering, roofing, aluminium foil coating/laminating, paper coating, extrudable moulds and profiles, electronic component parts, and wire and cable coating and jacketing. Medical devices comprise approximately 25% of total manufacturing use of DEHP in the USA. Medical devices that contain DEHP include PVC sheet materials such as intravenous bags, and tubing used in a variety of medical applications.

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).