Common Phthalates Implicated in Thyroid Function Disturbance in Young Girls

Phthalates are chemicals found in common household products, including shampoos, plastic toys, building materials, and nail polish. They are typically used in polyvinyl chloride plastic products, and widely used in healthcare. Despite their ubiquitous nature in home, hospital, and school settings, the link between phthalate exposure and thyroid function in children over time has not been well studied.

In a May 2017 study published in Environment International, researchers measured five phthalates and two thyroid hormones from 229 pregnant women and 229 children who were three years old. They found early childhood exposures to specific phthalates were associated with depressed thyroid function in girls at age 3, according to the scientists. In particular, lower levels of the active thyroid hormone free thyroxin (FT4) were associated with the group of phthalates mono-n-butyl phthalate (MnBP), mono isobutyl phthalate (MiBP), monobenzyl phthalate (MBzP), and monoethyl phthalate (MEP). The researchers plan to continue to study the health of the children as they get older in order to better understand the long-term impact of these exposures on thyroid function.

"The thyroid acts as the master controller of brain development," says senior author Pam Factor-Litvak, professor of epidemiology at Columbia University’s Mailman School of Public Health. "Thyroid hormones set the schedule, and if the timing is out of sync, there may be later consequences in the brain. The thyroid disruptions we see in this study, although they fall within the normal range, could explain some of the cognitive problems we see in children exposed to phthalates, and we are currently investigating that. As we know from lead, even small exposures can make a big difference."

As more research unfolds and we better understand the full extent of the health implications, health care institutions can take steps to remove phthalates from their facilities. Health Care Without Harm's Safer Chemicals Campaign, Healthier Hospitals Safer Chemicals Challenge, and Practice Greenhealth provide guidance and resources those who are interested in healthier furniture and medical devices.

[Source: Science Daily]