Infants and toddlers exposed to baby lotions, shampoos and powders carry high concentrations of hormone-altering chemicals in their bodies that might have reproductive effects, according to a new scientific study of babies born in Los Angeles and two other U.S. cities.
The research, to be published today in the medical journal Pediatrics, found that as the use of baby care products rose, so did the concentration of phthalates, which are used in many fragrances.
The lead scientist in the study, Dr. Sheela Sathyanarayana of the University of Washington's Department of Pediatrics, said the findings suggested that many baby care products contain a variety of phthalates that enter children's bodies through their skin.
Manufacturers do not list phthalates as ingredients on labels, so it is unknown which products contain them.
The researchers at the University of Washington and the University of Rochester stressed that the potential effects on babies were uncertain. But previous animal and human research suggests that early exposure to some phthalates could reduce testosterone and alter reproductive organs, particularly in males.
The three phthalate compounds found in the highest concentrations in babies in the study were linked to reduced testosterone in a 2006 study of newborns in Denmark. Some scientists theorize such changes in hormones could lead to fertility problems and male reproductive disorders.
Representatives of the fragrance and cosmetics industries said they were surprised by the findings and questioned their validity. They said only one phthalate compound is used in baby products, and it is found in such low levels that they doubt it could explain high concentrations found in the babies.
In the study, doctors tested the urine of 163 children between the ages of 2 months and 28 months born in Los Angeles, Minneapolis and Columbia, Mo., between 2000 and 2005. All had detectable amounts of at least one type of phthalate, and more than 80% had seven or more types.
"Phthalate exposure is widespread and variable in infants. We found that mothers' reported use of infant lotion, infant powder and shampoo was significantly associated with . . . urinary concentrations," the scientists wrote in the new study.
In the study, babies exposed to baby lotion, shampoo and powder had more than four times the level of phthalates in their urine than babies whose parents had not used the products. The highest levels were reported in babies under 8 months old, and those exposed to lotions.
