Dibutyl phthalate is a phthalate ester that is the diester obtained by the formal condensation of the carboxy groups of phthalic acid with two molecules of butan-1-ol. Although used extensively as a plasticiser, it is a ubiquitous environmental contaminant that poses a risk to humans. It has a role as an environmental contaminant, a teratogenic agent, a plasticiser, a metabolite and an EC 18.104.22.168 (alpha-glucosidase) inhibitor. It is a phthalate ester and a diester. It derives from a butan-1-ol.