The Environmental Protection Agency has released findings of a recent study indicating that a currently unregulated phthalate, dipentyl phthalate (DPeP or DPP for short), may be more hazardous than any of the phthalates permanently banned by the Consumer Product Safety Improvement Act (DEHP, DBP, and BBP) as well as those under a temporary ban (DINP, DIDP and DnOP). Phthalates are widely used as softeners for plastics, primarily but not exclusively in PVC.

From Environmental Health News, a publication of the journal Environmental Health Sciences:

The results provide strong evidence that DPeP – a little known and understudied phthalate – may actually pose a greater risk to the developing male reproductive system than the better-known DEHP. DPeP was eight times more potent in reducing testosterone production, 3 - 6 times more potent in blocking gene activity, and 2 - 3 times more potent in causing male genital abnormalities.

Rats share many developmental similarities with humans, so there is good reason to think that prenatal exposure to DPeP would have similar effects on human male reproductive development. In both species, testosterone production during certain critical fetal periods is needed for the reproductive system to develop in characteristically masculine ways.

The study is important because it provides solid information about how prebirth exposure to different doses of DPeP affect male reproductive development. The authors have filled in data gaps that will help determine whether it, too, might warrant government regulation in the future. Several other less potent phthalate compounds have been identified for stringent regulatory actions by the U.S. Environmental Protection Agency Office of Chemical Safety and Pollution Prevention. [Link]

The EPA appears to be in the middle of an assessment process for evaluating the hazards of DPP which is set to conclude at the beginning of 2012.

ZRecs has advised companies to avoid all phthalates in their products. Unfortunately, some companies offering products claiming to be "phthalate-free" may be referring not to all phthalates, but to those specifically banned by CPSIA.