In our pursuit of lustrous, frizz-free hair through the use of oils, gels, and sprays, there might be a hidden health toll – the release of potentially harmful compounds, especially when coupled with heat styling tools.
Researchers in the United States delved into the world of volatile organic compounds (VOCs), including siloxanes, emitted during various at-home hair styling rituals.
It turns out, certain hair care products not only contribute to the inhalation of VOCs within homes but also have implications for outdoor air quality through ventilation systems.
The findings took even the researchers by surprise. Nusrat Jung, a civil engineer from Purdue University, expressed, “We found the results extremely alarming. We did not expect to see such significant emissions of volatile chemical mixtures from commercially available hair care products during typical hair care routines that many people perform every day.”
The researchers conducted 46 experiments in a breezy laboratory within a “tiny house,” where adults aged 18 to 65 mimicked their regular at-home hair care routines using various styling products and tools.
Throughout each hair care session, an advanced mass spectrometer measured VOC concentrations in the indoor air before, during, and after. The team explored the relationship between styling tool temperature, VOC emissions, ventilation conditions, and hair surface area.
Their focus was on cyclic volatile methylsiloxanes (cVMS), commonly found in hair care products. The results indicated that higher styling tool temperatures and larger hair surface areas were linked to increased VOC emissions.
“The use of hair care products led to rapid changes in the chemical composition of the indoor atmosphere,” the team noted. “cVMS dominated VOC emissions from hair care product use, and decamethylcyclopentasiloxane (D5) contributed the most to cVMS emissions.”
D5, a popular ingredient in styling products, is stable at high temperatures and provides a smooth texture. However, it has been shown to have adverse effects on the respiratory tract, liver, and nervous system of laboratory animals, prompting restrictions in the European Union.
While further studies in humans are needed to fully understand the health implications, measurements revealed that an individual could inhale up to 20 mg of D5 per day. Fortunately, ventilation, such as using a bathroom exhaust fan, could reduce inhalation exposures to D5 by over 90 percent.
Yet, this comes with an environmental trade-off. Turning on the exhaust fan increases the cumulative indoor-outdoor D5 emission in one hour compared to three hours without fan use.
Jung emphasized, “So even if using products with harmful chemicals is not part of your hair care routine, you will still be impacted due to your urban environment.”
Acknowledging the limitations in modeling inhalation and inside-out emissions, the researchers suggest leaving the room immediately after hair styling to reduce exposure. Still, Jung’s ultimate recommendation is clear: “The best solution is simply not to use these products. The effects on people and the planet need to be studied further, and regulatory action taken.”
This eye-opening study was published in Environmental Science and Technology.