Science and Tech


'Alarming' amount of chemicals inhaled from hair products, study says

On average, a person can inhale up to 17 milligrams of potentially harmful chemicals in a single hairstyling session, according to the research.
Woman using a hair care product
Posted at 3:02 PM, Dec 05, 2023

Americans inhale an “extremely alarming” amount of chemicals that linger in the air from their hair care products, according to a new study from researchers at Purdue University

On average, a person can inhale up to 17 milligrams of potentially harmful chemicals in a single hairstyling session, based on the research performed by Nusrat Jung, an assistant professor in Purdue’s Lyles School of Civil Engineering. 

Most of the chemicals that were found to be inhaled are variations of organosilicon compounds, such as cyclic volatile methyl siloxane and decamethylcyclopentasiloxane, otherwise known as D5 siloxane. 

The study, which was published in the American Chemical Society’s Environmental Science and Technology journal, said these chemicals were found in most hair products, often being listed as one of the first or second ingredients. These types of chemicals are commonly added to the products due to their “low surface tension, inertness, high thermal stability and smooth texture.

“D5 siloxane has been found to lead to adverse effects on the respiratory tract, liver and nervous system of laboratory animals,” Jung said. “The use of the chemical in wash-off cosmetic products has already been restricted in the European Union because of this.”

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While there have been previous studies on the effects of these chemicals in “wash-off” products such as shampoo, there’s been little to no research on potential effects from leave-in hair products like gels, creams, oils and sprays, according to Jung. 

Applying heat to hair after using these products increases the release of the chemicals into that air anywhere from 50% to 310%, researchers found. 

The harmful inhalants don’t just stay in one room either, the study found. The airborne chemicals can spread throughout your home and even outside of it, creating a damaging environmental impact. 

“We found the results to be extremely alarming,” Jung said. “We did not expect to see such significant emissions of volatile chemical mixtures from off-the-shelf hair care products during typical hair care routines that many people perform each and every day.”

Jung’s team did find some solutions to this concerning issue, however. 

For starters, the researchers said just don’t use the products. The next best solution would be to have an exhaust fan running in the room you’re using the products in, or some type of ventilation system in place. While that won’t help the environmental concerns, it can decrease the amount you inhale. 

“There’s a good reason why these chemicals are restricted from being used in wash-off hair care products in certain parts of the world,” Jung said. “The effects on people and the planet need to be studied further and regulatory action needs to be taken.”