A research project undertaken collaboratively by researchers at a number of major US medical schools has found a link between in utero exposure to diethylhexyl phthalate (DEHP) and male genital development in newborns. The effects are minor but are believed by the researchers to be statistically significant. DEHP is a phthalate that is used mainly in PVC plastic to make it more pliable but is also found in packaging, some hydraulic fluids, electrical devices (capacitors), some glowsticks, and plastics associated with medical devices. One estimate is that about three million tonnes are produced worldwide each year. Most of this will eventually find its way into the environment. The male genital abnormality identified by the researchers is characterized as the anogenital distance (AGD). AGD, the distance between the anus and the genitals, is already known to be a biomarker of prenatal androgen (male characteristic hormone) exposure. The researchers found:
- concentrations of diethylhexyl phthalate (DEHP) metabolites in first trimester maternal urine samples are inversely (adversely) associated with AGD in male, but not female, newborns.
- even at current low levels, environmental exposure to DEHP can adversely affect male genital development resulting in reproductive tract changes that may impact reproductive health later in life.
- these findings have important implications for public policy since most pregnant women are exposed to this ubiquitous chemical.
This is by no means the first time that GallonDaily has written about the possible endocrine disrupting effects of phthalates – enter phthalates into the search box at http://www.GallonDaily.com to see previous articles. DEHP is classified in the European Union as a Category 1B reproductive toxicant, a presumed but not proven human reproductive toxicant. In Canada the concentration of DEHP is restricted by regulation in soft vinyl children’s toys and child care articles where the soft vinyl can, in a reasonably foreseeable manner, be placed in the mouth of a child under four years of age. There are no regulations which serve to limit fetal exposure to DEHP in the womb.
An abstract and the full paper from which this brief summary is drawn will be published in the peer reviewed Oxford University Press journal Human Reproduction and are currently available at http://humrep.oxfordjournals.org/content/early/2015/02/03/humrep.deu363.full.pdf+html