Metabolism of phthalates in humans

Mol Nutr Food Res. 2007 Jul;51(7):899-911. doi: 10.1002/mnfr.200600243.


Phthalates are synthetic compounds widely used as plasticisers, solvents and additives in many consumer products. Several animal studies have shown that some phthalates possess endocrine disrupting effects. Some of the effects of phthalates seen in rats are due to testosterone lowering effects on the foetal testis and they are similar to those seen in humans with testicular dysgenesis syndrome. Therefore, exposure of the human foetus and infants to phthalates via maternal exposure is a matter of concern. The metabolic pathways of phthalate metabolites excreted in human urine are partly known for some phthalates, but our knowledge about metabolic distribution in the body and other biological fluids, including breast milk, is limited. Compared to urine, human breast milk contains relatively more of the hydrophobic phthalates, such as di-n-butyl phthalate and the longer-branched, di(2-ethylhexyl) phthalate (DEHP) and di-iso-nonyl phthalate (DiNP); and their monoester metabolites. Urine, however, contains relatively more of the secondary metabolites of DEHP and DiNP, as well as the monoester phthalates of the more short-branched phthalates. This differential distribution is of special concern as, in particular, the hydrophobic phthalates and their metabolites are shown to have adverse effects following in utero and lactational exposures in animal studies.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Child, Preschool
  • Diethylhexyl Phthalate / adverse effects
  • Diethylhexyl Phthalate / analysis
  • Endocrine Disruptors
  • Environmental Exposure
  • Female
  • Humans
  • Infant
  • Maternal-Fetal Exchange
  • Milk, Human / chemistry
  • Phthalic Acids / adverse effects
  • Phthalic Acids / analysis
  • Phthalic Acids / metabolism*
  • Phthalic Acids / pharmacokinetics
  • Phthalic Acids / urine
  • Pregnancy
  • Tissue Distribution


  • Endocrine Disruptors
  • Phthalic Acids
  • diisononyl phthalate
  • Diethylhexyl Phthalate