Chemicals often used in vinyl flooring and PVC may make pregnant women more susceptible to heart diseases, according to a new study. It builds on other studies that concluded that certain phthalates, also found in plastics, cosmetics, fragrances and—by extension, most of us—may impact heart health.
The researchers looked at phthalate levels in the urine of 369 pregnant women during their pregnancy. They also monitored blood pressure and any pregnancy-induced heart problems.
The body breaks down phthalates into metabolites. Researchers found that women with the highest levels of a common phthalate metabolite were almost three times as likely to have pregnancy-induced high blood pressure than women with the lowest levels.
“Pregnancy is kind of like a stress test,” said lead author Dr. Erika Werner, an assistant professor at Brown University’s Alpert Medical School. She said many women who develop heart problems later in life experience high blood pressure and related complications during pregnancy.
"Pregnancy is kind of like a stress test."-Dr. Erika Werner, Brown UniversityThe metabolite that was linked to the heart problems is a by-product of butyl benzyl phthalate, most commonly used to make PVC and vinyl foams flexible and pliant.
People are exposed to such phthalates through inhalation, skin absorption and by eating or drinking. Scientists believe phthalates can migrate out of flooring and contaminate indoor air.
Exposure to butyl benzyl in the U.S. has decreased an estimated 32 percent from 2001 to 2010, according to a 2014 study. However most U.S. women are still exposed, Werner and colleagues warned. The study sampled women from the Cincinnati, Ohio, region between 2003 and 2006.
“The population impact could be substantial because exposure to the parent compound of this metabolite, butyl benzyl phthalate, is ubiquitous in U.S. women,” the authors wrote in the study, published last month in Environmental Health.
How the chemical might spur heart problems remains unclear. However, experts believe it’s most likely through inflammation and oxidative stress, an imbalance in the body that hampers its ability to detoxify.
“Oxidant stress is well known to fuel cardiovascular disease, and certain phthalates are oxidant stressors,” said Leo Trasande, a researcher and associate professor in pediatrics, environmental medicine and health policy at the New York University School of Medicine, in an email. He was not involved in the study.
Trasande and colleagues in 2013 reported the phthalate levels in children’s urine was linked to higher blood pressure.
The study did not find any links to the other phthalates metabolites and heart impacts, which Werner said suggests the phthalate linked to high blood pressure might be more prone to affecting cells that impact heart health.
She cited a study published last year that supports this, as the same phthalate was linked to plaque buildup in the arteries of elderly folks.
Werner’s study is the latest that raises questions about the safety of phthalate exposure, as previous animal tests and some human studies have linked them to hormone disruption, altered male genital development, diabetes, asthma, attention, learning disabilities and obesity.
The American Chemistry Council, which represents chemical manufacturers and maintains that typical human exposure to phthalates is safe, doesn’t represent the phthalates mentioned in the study. It did not comment on the findings.