Infants whose parents applied baby lotions, powders and shampoos to their young skin had elevated levels of a chemical believed to harm developing endocrine and reproductive systems, according to a study published today.
The more products that parents applied, the higher the level of the chemical, according to one of the first studies to examine how babies are exposed to phthalates through their skin, as opposed to ingesting or inhaling the chemicals.
Phthalates (pronounced THA-lates) - a family of nearly ubiquitous chemicals used to make plastic toys softer, fragrances last longer and medical tubing flexible - are banned in toys and personal care products in the European Union.
"We don't really know what the health effects are," said Dr. Sheela Sathyanarayana, a pediatrician at the University of Washington and lead author of the study published in today's edition of the journal Pediatrics. "The theory from a lot of scientists is, we're changing reproductive health over time."
Industry researchers dispute any association made between baby care products and increased phthalate levels in children.
Dr. John Bailey, chief scientist at the Washington-based Personal Care Products Council, said the findings "really don't make sense." Of the seven phthalates that Sathyanarayana's study found in the infants, only one is used in baby products and that one only in small amounts, he said.
"If they're finding them, they're coming from somewhere else," Bailey said.
The study involved 163 children, mostly under the age of 2, whose wet diapers were collected and analyzed for evidence of metabolized phthalates. Their mothers filled out questionnaires asking which, if any, baby care products they had used on their children over the previous 24 hours.
All of the children, even those as young as two months, had measurable phthalate levels, but more than 80 percent had seven or more phthalates detectable in their urine. The more baby care products used, the study found, the more phthalates researchers found, a correlation that was strongest in babies under 8 months old.
Sathyanarayana and her colleagues did not test the baby care products themselves, but note that phthalates have been found in many adult personal care products.
Not enough is known about phthalates to determine whether the levels detected in the children are safe, Sathyanarayana said. "We don't know what a toxic concentration might be of these chemicals in humans," she said.
The debate over phthalates has heated up in recent years, as more research has been conducted on the chemicals. Animal studies have shown that some phthalates are endocrine disrupters associated with birth defects, fertility problems and testicular tumors.
In humans, there have been fewer studies, but phthalates have been linked to low sperm count and other reproductive problems as well as obesity and insulin resistance.
"There is now a substantial human literature on phthalates and abnormalities in males," said Dr. Frederick vom Saal, a University of Missouri endocrinologist who was instrumental in getting phthalates banned in Europe.
One reason there are few studies on phthalates and newborns is because it is difficult to do research on babies and fetuses, he said. Still, he said, the younger the person is when exposed, the more likely that the chemical will have permanent effects.
Children are exposed to phthalates in many ways: the chemicals are in soft plastic toys such as rubber ducks, which infants and toddlers wind up sucking. They have been found in breast milk and as contaminants in food, soil and air.
Sathyanarayana advises parents not to use baby lotions, powders and shampoos on their children unless medically necessary. Unscented soaps can be used to wash babies, she said.
"Infants don't need those products," she said. "They have very sensitive skin. I hear from moms again and again that you get sent home [from the hospital after giving birth] with this whole package of stuff for your baby. These products are not essential."
Jane Houlihan, vice president for research for the Environmental Working Group, a nonprofit environmental research organization based in Washington, said, "This study really raises a lot of concern. Parents use these products to keep their babies' skin soft, thinking they're doing the right thing. .... This study shows it's not just toys."
The Food and Drug Administration has looked into phthalates in cosmetics and considers them safe as used in those products. It found no reason to take regulatory action.
Last year, California became the first state to bar the use of phthalates - six of them - in toys and other products that end up in children's mouths. The prohibition will go into effect next January. One Maryland lawmaker has proposed similar legislation, though the same bill went nowhere last year. Lawmakers in Connecticut and other states are considering phthalate bans.
Industries that use phthalates defend the use of these products.
"There is no reliable evidence that any phthalate has ever caused any harm to any human in their fifty-year history of use," notes the American Chemistry Council's Phthalate Information Center Web site. "Phthalates are one of the most thoroughly tested families of compounds in use today."
Bailey criticized Sathyanarayana's group for not testing the products themselves, saying that it leaves a hole in the research.
Houlihan said she advises parents to carefully read the labels of anything they use on their children. But many phthalates are not identified there.
The FDA requires that ingredients be listed, except for when a fragrance is used. The components of a fragrance are considered proprietary information and do not have to be listed. In baby care products, Houlihan said, researchers believe that's where the phthalates are.
Charles Margulis, spokesman for the Center for Environmental Health, an Oakland, Calif.-based nonprofit that is conducting chemical studies of baby care products, said he worries about youngsters' frequent exposure to phthalates.
Even if each exposure is small, he said, "kids are getting exposed all the time, and those exposures are going to add up."
He likened the conversation about phthalates today to the discussion about another chemical half a century ago.
"Fifty years ago, they said a little lead won't hurt. Today, everyone knows there shouldn't be lead in kids' products," he said.
"The health effects of phthalates are severe and can be lifelong. So why risk it?"
stephanie.desmon@baltsun.com