A doctor who studies toxic chemicals explains why he avoids paper receipts at the store

• Receipts often contain bisphenols, which are chemicals linked to reproductive toxicity and cancer.
• That's because receipts are coated in a plastic polymer for heat-based printing.
• Dr. Leonardo Trasande from NYU Langone says he opts for email and text receipts when possible.

Plastics and the chemicals they carry are everywhere, from our air, water, and blood to the products we use every day.

Researchers like Dr. Leonardo Trasande know the unexpected places where these chemicals sneak into our lives, like the receipts you get at grocery stores, gas stations, restaurants, and clothing outlets.

"We don't think of thermal paper receipts as plastic, but that shiny coating is a polymer on top," Trasande, a professor of pediatrics and environmental health researcher at NYU Langone, told Business Insider.

Trasande's main complaint about receipts is what that plastic polymer puts into human skin.

Where there is plastic, he added, "chemicals of concern come along for the ride."

When it's an option to receive his receipt by email or text, Trasande goes for that.

Toxic chemicals on store receipts

Receipts are usually made of thermal paper, which is designed to print using heat-sensitive inks. That makes for cheap and easy on-the-spot printing in restaurants and businesses.

The problem is that this thermal paper usually contains bisphenols, a class of chemicals used to manufacture plastics.

The most famous bisphenol, called BPA, has been linked to heart disease, decreased fertility, breast and prostate cancers and, in children, asthma and neurodevelopmental issues. BPA has been phased out of US products over the past decade, including receipts.

However, studies have found that many receipt manufacturers have replaced the BPA with its cousin BPS, which is banned in Europe for use in food containers, considered a reproductive toxin by the state of California, and has been associated with breast cancer.

If you touch a receipt that's coated in BPS, the toxic chemical can quickly enter your body by absorbing through your skin, according to recent research.

This year, the nonprofit watchdog Center for Environmental Health tested receipts from 32 major retailers and found that touching one for 10 seconds would expose someone to enough BPS to legally require a warning in California. Under the state's Proposition 65, businesses must provide warnings about significant exposures to chemicals that cause cancer or reproductive harm. The CEH delivered a legal notice to those 32 retailers in April.

"Chemicals used in plastic materials need to be properly vetted for safety," Trasande said. "Insofar as chemicals are identified to be toxic to human health, we have safer alternatives that should be considered."

He called electronic receipts "an important positive step forward."

Microplastics in receipts

Underlying the bisphenols, of course, is plastic. Though Trasande said there is much more definitive research on the health effects of many chemicals in plastics, emerging science about the proliferation of plastics themselves throughout the human body is not comforting.

The plastic items that surround us all in our homes, workplaces, schools, and even the outdoors are shedding tiny particles called microplastics — or, when they get really tiny, nanoplastics.

These minuscule plastics build up in our bodies. They've been found in almost every human body tissue researchers have checked, from the brain to the lining of the arteries. Their health impacts are not yet clear, but they've been linked to chronic inflammation, lung and colon cancers, reproductive health issues, and heart attack and stroke risk.

"There are limits to what I can control," Trasande said. "At the same time, there are so many steps we can take to reduce our exposure to chemicals of concern and particularly micro- and nanoplastics."

Declining paper receipts is one of them. On the whole, though, Trasande said the world needs to reduce its plastic production.

If business as usual continues, plastics production is expected to triple by 2060, according to the United Nations Environment Programme.

Trasande said a global plastics treaty would help. According to Reuters, the United Nations is set to resume negotiations for such a treaty in August.