But a new study shows that an infant with a typical diet is still consuming twice as much of the chemicals as the Environmental Protection Agency considers safe. Meats -- poultry in particular -- high fat dairy products such as whole milk and cream, cooking oils and fats such as margarine all contain high levels of the chemicals, according to the research, published in June in the journal Environmental Health. As a result, infants and toddlers who consume solid food are still taking in too much of them, said one of the researchers, Sheela Sathyanarayana, an associate professor of pediatrics at the University of Washington School of Medicine.
"When the children’s toys were being brought up, it was specifically for kids mouthing a lot of plastic toys," said Sathyanarayana, who is also an investigator at the Seattle Children's Research Institute. "Now that we have more information and the research has evolved, we know [there are] other sources." In addition to diet, those would be dust tracked into homes by everyday foot traffic and the creams and lotions used mostly by women for personal care.
Phthalates, a family of chemicals, have been used for decades to make plastic more pliable and cosmetics smoother. They are considered endocrine disruptors; a growing body of research appears to indicate that they interfere with hormones such as testosterone and therefore the quality of sperm and semen.
Sathyanarayana and a team of researchers reviewed 17 studies that measured phthalate concentrations in food in the United States and abroad, then created models for four types of diet: one high in fruits and vegetables, one high in meat and dairy, a balanced diet based on government guidelines and a typical American diet. As expected, the fruit and vegetable diet did not expose its consumers to excessive levels of phthalates, and the one high in meat and dairy was unsafe for infants and adolescents. The typical U.S. diet was safe for adults, but the researchers were surprised when they determined that it far surpassed the limit of 20 micrograms of phthalates per kilogram of body weight per day that the EPA has set as a safe level for infants and toddlers.
The study did not look at how the chemicals came to be highly concentrated in certain foods, but Sathyanarayana said poultry, for example, may be contaminated by packaging and chicken feed; milk may pick up phthalates from plastic tubes that conveys it from cow to container. Fresh fruits and vegetables, in contrast, undergo the least amount of processing and contain lower levels of the chemicals.
The good news is that there steps parents can take to minimize children's exposure to phthalates. Because phthalates leach from plastic when it is heated, food should not be warmed in plastic containers, especially those that have the number 3 as an identifier of their composition, Sathyanarayana said. Use glass or ceramic instead, she said.
Other tips from the researchers include:
- Buy low fat dairy products such as skim milk and low fat cheeses. Avoid high fat foods such as cream, whole milk and fatty meats.
- Buy fresh or frozen fruits and vegetables. Avoid canned and processed foods.
- Minimize the use of personal care products that contain phthalates.
- Use glass, stainless steel, ceramic or wood to hold and store foods instead of plastics.
- Do not use hard, polycarbonate plastics to hold hot liquids.
- Minimize handling of receipts, which contain chemicals.
- Take shoes off at the front door to avoid tracking in dust that may contain these chemicals.
- Keep carpets and window sills clean. Vacuum and wet dust frequently to minimize dust that may contain chemicals.