The study, led by Sheela Sathyanarayana from the University of Washington, claims there is a link between infant exposure to baby care products and the amount of phthalate derivatives found in the urine. Phthalates are a family of chemicals often used in personal care products and fragrances, as well as plastic toys and pacifiers. Although little scientific evidence suggests that the chemicals have negative effects on the human body, animal studies highlight the impact they could have on sexual development and other hormone related problems. Infant exposure to phthalates may come from a wide variety of sources including exposure to phthalate-containing baby care products such as lotions, powders and shampoos, according to Sathyanarayana and the team. The study investigated the presence of 9 phthalate metabolites in the urine of 163 infants. Exposure to baby care products was estimated from parental reports of product use in the 24 hours prior to the urine sample. Sathyanarayana and the team found that the reported use of baby lotion, powder and shampoo was significantly associated with the concentrations of monoethyl phthalate (MEP), monomethyl phthalate (MMP) and monoisobutyl phthalate (MiBP) in the urine samples. "These findings suggest that dermal exposures may contribute significantly to phthalate body burden in this population," conclude the researchers. However, even if this is the case, the effect such chemicals have on infants remains to be seen. "We do not know whether early childhood phthalate exposure leads to adverse developmental effects in the future" said the researchers, adding that more research is needed in this area to understand the toxicities involved. In addition, the scientists draw attention to the fact that under US law manufacturers are not obliged to place phthalates on the ingredients list so it is difficult for consumers to avoid the chemicals. Phthalates have attracted significant criticism of late and a number of interest groups have called for tighter regulation or outright bans on their use in personal care products. In September, the Natural Resources Defense Council (NRDC) warned consumers to avoid exposure to the phthalate DEP, which helps fragrances linger after application. While the consumer group claimed DEP posed a serious health risk, the Fragrance Materials Association (FMA) and the European Commission's Scientific Committee on Consumer Products (SCCP) both insist that DEP is safe for use in cosmetics at current levels.