Pregnancy/Pre-term Birth/Exposure in Infants
Research and developed by Sarah (Steve) Mosko, Ph.D.
Updated Nov. 2004. For references click here.
Decreased rates of pregnancy and higher rates of miscarriage have been found in female factory workers exposed chronically to high levels of phthalates.(17) Pregnancy complications correlated with higher urinary phthalate levels in women living near a plastics manufacturer.(18) A study in pregnant women in New York City and Krakow, Poland showed that everyday breathing is an important route of exposure to phthalates. Urinary levels of phthalates were tracked along with levels of phthalates in "personal air" samples (the women wore air samplers around their necks for 48 hours), and the fact that urinary levels followed the levels in air indicates that inhalation is a significant route of pre-natal exposure.(86)
- Pre-term birth rates are rising in the US. A recent study found that the majority of neonates born in an Italian hospital had phthalates DEHP (and MEHP, the active metabolite of DEHP) in cord blood, and those with elevated levels had one week shorter gestation. These findings confirm that human exposure to DEHP can begin in utero (it crosses the placental barrier) and can contribute to premature birth.(10)
- A study of 19 teenagers who had received intensive care right after birth, several days attached to blood-oxygenating plastic PVC tubing, showed no gross abnormalities in physical growth or pubertal maturity and had age-appropriate levels of sexual hormones.(52) This in no way proves that DEHP is not harmful to newborns, as the study had several limitations. Importantly, DEHP exposure was intravenous, and conversion to the toxic metabolite MEHP takes place primarily in the intestinal tract, making the oral route potentially much more harmful than intravenous exposure. Also, DEHP exposure was never measured, only guessed at, and only gross measures of sexual development were applied. Subtle internal abnormalities could have been missed, and furthermore, critical developmental periods of sensitivity to DEHP exposure in humans have not yet been delineated. Nevertheless, this study is a first-of-its kind and illustrates the need for human studies of phthalate exposure at various developmental stages.
- National Institutes of Health expert panel concluded in 2000 that the known reproductive and developmental effects of DEHP raised substantial concerns about exposure in infants and pregnant women. The panel recognized a lower level of concern about children exposed to DINP through mouthing plastic toys. The following is copied directly from their report.(68) Many studies are ongoing about the toxicity of these and other phthalates.
- For di (2-ethylhexyl) phthalate (used in building products, food packaging, children's products and medical devices) there was "serious concern" for the possibility of adverse effects on the developing reproductive tract of male infants exposed to very high levels of DEHP that might be associated with intensive medical procedures such as those used in critically ill infants. The Panel recognized the health benefits of these procedures. There was "concern" that exposure of pregnant women to current estimated adult exposure levels of DEHP might adversely affect the development of their offspring. The Panel expressed "concern" that, if infants and toddlers are exposed to levels of DEHP substantially higher than adults, adverse effects might occur in the developing male reproductive tract. The Panel expressed "minimal concern" that current exposures of adults to DEHP would adversely affect the reproductive system. For di-isononyl phthalate (used in garden hoses, shoes/shoe soles, toys, construction materials), the Panel expressed "minimal concern" for adverse developmental outcomes resulting from exposure of pregnant women and "minimal concern" for adverse effects on the reproductive system of exposed adults. There was "low concern" for potential health effects in children who might be exposed to DINP through the mouthing of toys or other DINP-containing objects.
Pediatricians call for research into risks to children
The American Academy of Pediatricians issued a report in June of 2003 outlining concerns about possible risks of elevated pediatric exposures to phthalates (DEHP and DINP) through diverse routes including medical devices, toys, foods, breastfeeding and indoor air. Particular concern was expressed about ill neonates whose exposure levels are especially high as a result of undergoing medical procedures.(83) The pediatrician group called for further research into both the toxicity of phthalates in pediatric populations and the development of safer substitutes.(67, 83)