Southern California study finds high levels of airborne plasticizers

A new study documents how Southern Californians are chronically exposed to toxic airborne chemicals called plasticizers, including one that has been banned in children’s items and beauty products.

Plasticizers are chemical compounds that make materials more flexible. They are used in a wide variety of products from lunch boxes and shower curtains to garden hoses and upholstery.

“It’s not just for straws and grocery bags,” said David Volz, a professor of environmental sciences at UC Riverside and corresponding author of an article on the study published in the journal Environmental research.

Previous California monitoring programs focused on plasticizers called orthophthalates, some of which have been phased out of manufacturing processes for health and environmental reasons. Less research has focused on the health effects of their substitutes, called non-orthophthalates.

This study found the presence of both types of plasticizers in the air throughout Southern California.

“The levels of these compounds are skyrocketing,” Volz said. “We didn’t expect that. As a result, we thought it was important for people to know about this study.”

This study is one of the few to document the presence of phthalates in the air of urban environments. The researchers followed two groups of UCR undergraduate students from different areas of Southern California. Both groups wore silicone bracelets designed to collect data on chemical exposures in the air.

The first group wore their bracelets for five days in 2019, and the second group wore two different bracelets for five days each in 2020. Both groups wore the bracelets continuously, all day, while they went about their business. activities. At the end of the data collection period, the researchers cut the bracelets into pieces and then analyzed the chemicals they contained.

In a previous paper, the team focused on TDCIPP, a known flame-retardant carcinogen, detected in the bracelets. They found that the longer a student’s commute, the higher their exposure to TDCIPP.

Unlike TDCIPP, which most likely migrates out of commuters’ car seats into dust, the team cannot identify the origin of the plasticizers. Because they are airborne rather than dust-bound, the bracelets could have picked them up anywhere, even outside of students’ cars.

For every gram of chopped bracelet, the team found between 100,000 and 1 million nanograms of three phthalates, DiNP, DEHP and DEHT. Ten plasticizers in total were measured, but the levels of these three stood out.

Both DiNP and DEHP are listed under California Proposition 65, which contains chemicals known to cause cancer, birth defects or other reproductive harm. DEHT has been introduced as an alternative, but its effects on human health have not been well studied.

This study suggests that the introduction of DEHT also did little to reduce the level of public exposure to DiNP or DEHP. The levels of the three chemicals found by Volz and his team were similar to those found by researchers in independent studies conducted on the East Coast.

Despite climate differences, the air on both coasts likely contains similar levels of phthalates.

“No matter who you are or where you are, your daily exposure level to these chemical plasticizers is high and persistent,” Volz said. “They are omnipresent.”

For Volz, studies like this amplify the need to find alternatives to plastic. As plastics degrade, these and similar compounds leach into the environment and the body.

“The only way to decrease the concentration of plasticizers in the air is to decrease our production and consumption of materials containing plasticizers,” he said.