Shea, KM and the Committee on the Environment. 2003. Pediatric exposure and potential toxicity of phthalate plasticizers. Pediatrics 111:1467-1474.

Background on phthalates
Recent scientific findings on phthalates and sperm

In a review of the possible health risks created by exposure in the womb and during early childhood, the American Academy of Pediatrics' Committee on the Environment finds that there are too few human studies to conclude phthalates are safe. None have examined risks to fetuses in the womb or during early childhood. Yet animal studies clearly establish that these life stages are the most sensitive to phthalate exposures. The pediatricians write that "Phthalates are animal carcinogens and can cause fetal death, malformations,and reproductive toxicity in laboratory animals." And they call for research on the effects of phthalates on vulnerable times of life, particularly in the womb and during early childhood.

In the meantime, a series of studies inarguably establish widespread human exposures. And as the Academy report notes, replacements for phthalate uses could be designed. Indeed, in two common uses of phthalates creating exposures today--for cosmetics and certain types of medical equipment--replacements are already available.

Their review concludes with a series of cautiously worded findings, summarized below:

• Phthalates are of concern because of known toxicities established through animal experiments.
• Human exposure to phthalates is universal. Food is considered to be the major source of exposure to DEHP and DINP; medical exposures are also important for DEHP.
• While data indicate that DEHP and DINP are animal carcinogens, the mechanisms involved may not be relevant to carcinogenesis in people. Both, however, are developmental toxicants, with the developing male reproductive system the most sensitive system identified to date. These mechanisms are different from those involved in carcinogenesis.
• "No studies have been performed to evaluate human toxicity from exposure to these compounds." [ed. note: actually in Winter 2002/Spring 2003, three studies were published suggesting adverse effects in adult men's sperm quality.]
• Children may be at higher risk of adverse effects of phthalates, "because of anticipated higher exposures during a time of developmental and physiologic immaturity."
• Exposures to DEHP resulting from the use of DEHP-containing PVC-made medical equipment "are of concern." Doses within the range of those caused by intensive medical treatment are known to cause damage to the immature male reproductive tract in animals. "No studies evaluate the effect of medical exposures to DEHP and [its metabolite] MEHP on testicular function in humans."
• Medical institutions may find it necessary to reassess uses of phthalate-containing medical equipment, including in neonatal and pediatric intensive care units. While phthalate-containing PVCs offer some advantages, "interventions designed to minimize DEHP exposure in the medical setting could be designed.
• Better data on phthalate exposures in the womb and in childhood, and about phthalate toxicology in general, would help guide decisions about risks and replacements. This should include research into phthalates effects on non-human primates as well as studies of sensitive human populations, such as pregnant and lactating women, premature infants, full-term infants, and children.

While this assessment falls far short of resolving the very public controversy over health risks of phthalate exposure, it does serve to disprove unequivocally the frequent assertion by industry that decades of experience and exposure to phthalates establishes their safety: Absence of proof of harm of phthalates can only be taken to be proof of ignorance, not a demonstration of safety.