Pregnant and breastfeeding women should avoid products that contain phthalates, says new research that links the chemicals to allergic asthma.

pregnant woman with painted nails, phthalates exposure
Credit: Vladislav Lazutin/Shutterstock

There are plenty of things to worry about coming into contact with during pregnancy—something I can attest to as a soon-to-be fourth-time mom.

Now a new study published in the Journal of Allergy and Clinical Immunology finds exposure to phthalates during pregnancy and while breastfeeding may increase a child's risk of developing allergic asthma.

Unfortunately, according to a press release, we come in contact with plastics containing plasticizers, including phthalates, every day. In fact, according to the Food and Drug Administration, they can be found in toys, vinyl flooring and wall covering, detergents, lubricating oils, food packaging, pharmaceuticals, blood bags and tubing, and personal care products such as nail polish, hair sprays, aftershave lotions, soaps, shampoos, perfumes, and other fragrances. They can enter our bodies via the skin, food, or respiration, and according to, under our federal laws, it's impossible to know for sure all products in which phthalates may be found.

"It is a well-known fact that phthalates affect our hormone system and can thereby have an adverse effect on our metabolism or fertility. But that's not the end of it," UFZ environmental immunologist Dr. Tobias Polte elaborated in the press release about the new research. "The results of our current study demonstrate that phthalates also interfere with the immune system and can significantly increase the risk of developing allergies."

Researchers looked at the urine of pregnant women to measure the byproducts of exposure to phthalates. And as Dr. Irina Lehmann explained, "There was a clearly discernible relationship between higher concentrations of the metabolite of benzylbutylphthalate (BBP) in the mother's urine and the presence of allergic asthma in their children."

A mouse model confirmed the results. As Dr. Polte explained about these findings, "If the organism is exposed to phthalates during the early stages of development, this may have effects on the risk of illness for the two subsequent generations. The prenatal development process is thus clearly altered by the phthalate exposure."

It's believed exposure may actually alter genes, and further research will be needed to determine exactly which genes are responsible for kids developing allergies.

The takeaway: We don't know exactly how much exposure it takes to affect your child's chances of developing allergic asthma. And it's hard to determine exactly how much exposure you are getting on a daily basis. If you are concerned about your exposure, recommends contacting manufacturers to find out how much phthalate is in certain products you use. You can also purchase phthalate-free products whenever possible.

Melissa Willets is a writer/blogger and soon-to-be mom of 4. Find her on Facebook where she chronicles her life momming under the influence. Of yoga.