Researchers are suggesting that parents hold off on the lotions, creams, powders and shampoos they apply to their babies’ skin – unless those products are medically necessary.
Their study found that babies on whom these products have been used have higher urine concentrations of a family of chemicals known as phthalates than infants who haven’t had the products applied. And it’s likely that it’s through the skin that the smallest of these tots are being exposed.
Phthalates are found in a variety of products. They make plastics soft and pliable and are used in many personal-care products to hold fragrance and color. These chemicals are known to cause a host of maladies in laboratory animals, including undescended testicles and malformed penises – two birth defects that are on the rise in people.
According to the U.S. Centers for Disease Control and Prevention, the rate of boys born with hypospadia, or a malformed urethra, in the United States has doubled since the late 1960s.
There is no definitive evidence that phthalates can cause harm to human babies.
For consumers, figuring out whether a particular product contains phthalates is difficult. Federal laws do not require companies to label chemicals if they are not considered key or critical ingredients in a product.
“The consumer has no way to know when they pick up a bottle of lotion if this product contains this chemical,” said Patricia Hunt, a biologist at Washington State University, who has studied other chemicals thought to damage the reproductive system. “All a parent can do now is look for products that explicitly say they do not contain these chemicals.”
The research study, conducted by a team from the University of Washington, the CDC and the Rochester School of Medicine and Dentistry, is published today in the journal Pediatrics.
It has sparked a strong rebuke from the chemical companies’ trade group, the American Chemistry Council.
“In 50 or more years of use, no reliable evidence has ever been found that phthalates, either alone or in combination, causes negative health effects in humans,” said Marian Stanley, the council’sPhthalates Esters Panel manager, in a statement.
“We take great exception to any effort to draw unfounded conclusions that suggest human health risks are associated with the mere presence of very low levels of metabolized phthalates in urine,” she said.
Study of exposure
The Pediatrics study was designed to determine whether healthy babies from the general population were being exposed to phthalates. And if they were, said Sheela Sathyanarayana, the lead author of the paper, the question was: How?
Sathyanarayana, a pediatrician and environmental health researcher at the University of Washington, and her colleagues gathered information from a group of infants and mothers they had been following in California, Minnesota and Missouri.
They collected urine samples from 163 babies who ranged from 2 months to 28 months in age and asked mothers to fill out questionnaires that asked about product, toy and pacifier use.
In the urine samples, which were squeezed from wet diapers, the researchers looked for the chemical byproducts, or metabolites, of nine different phthalates.
They found that every baby they studied had at least one detectable phthalate metabolite in his or her urine, and more than 80% had seven or more different kinds.
They also discovered that babies whose mothers reported using infant lotion, infant powder or shampoo on their babies in the 24 hours before the urine sample was collected had the highest levels of phthalates. This relationship was especially strong in infants younger than 8 months.
“I was surprised that all of the younger infants were exposed,” said Sathyanarayana. “I would have thought that a newborn baby would have the least exposure because they are not crawling or walking. They’re not really being exposed to the outside environment as much as older children.”
She called the result particularly worrisome because newborns are especially susceptible to reproductive and developmental toxins.
Effects being explored
Sathyanarayana said with so little known about the effects of these chemicals, it’s wise not to use lotions, powder and shampoo on infants unless there is a medical reason to apply them.
The researchers also found phthalates in these babies that aren’t associated with lotions, powders or creams. That means they are presumably picking up these chemicals elsewhere, said Sathyanarayana – possibly ingesting them via breast milk and formula, or inhaling them from dust in their homes.
There has been enough compelling research on phthalate exposure in rodents and humans to raise some alarm, said Ted Schettler, science director of the Science and Environmental Health Network, an Iowa-based environmental health group.
In one study, the concentration of a specific phthalate metabolite in the urine of adult men was associated with sperm damage. In another study, conducted in part by three of the authors of the current paper, the researchers found a dose-dependent relationship between phthalate concentration in pregnant women and genital abnormalities in their newborn sons.
The preliminary research conducted in humans, as well as the hundreds of studies on animals, has been enough to spark both the European Union and California to ban some of these chemicals in children’s products.
But Schettler cautioned that Sathyanarayana’s study was not designed to look at the health impacts of phthalates on people.
“It just demonstrates that children are being exposed to phthalates,” he said, adding it also indicates that skin absorption of these chemicals may be more important than researchers had previously thought.
The current study also looked at diaper rash ointments, wipes, toys and pacifiers.
But the authors did not find a relationship between these items and phthalate urine concentrations.
Schettler said that unlike diaper creams, which are designed to provide a barrier between a diaper and a babies’ skin, products such as lotions contain chemicals designed to be absorbed by the skin. Therefore, it’s probably the presence of these chemicals that enables phthalates to penetrate the skin.