Hair Care Products Release Volatile Compounds, Affecting Indoor Air Quality

Seeking glossy hair may risk health. Researchers from the US found harmful compounds, such as siloxanes, emitted in hairstyling, could adversely impact indoor and outdoor air quality. However, the health consequences remain uncertain.

Hair Products May Pose Health Risks

Hair care products, containing substances that easily evaporate, may pose health risks as users can potentially inhale these chemicals. Recent research has delved into the emissions of volatile organic compounds (VOCs), including siloxanes, commonly found in products that enhance hair shine and smoothness.

The study, titled "Siloxane Emissions and Exposures during the Use of Hair Care Products in Buildings" published in ACS' Environmental Science & Technology, indicates that the use of such hair care products can swiftly alter indoor air composition, a process further intensified during common heat styling techniques like straightening and curling.

While previous studies have explored the release of siloxanes from personal care products, many concentrated on items washed off the body, such as skin cleansers. This research focuses on substances left on the hair, like creams and oils. Moreover, most prior investigations into siloxane emissions did not address the real-time changes in indoor air composition during active hair styling.

To fill this gap, Nusrat Jung and her team set up experiments in a ventilated tiny house, simulating real-world scenarios such as small bathrooms where hair products are typically applied.

Participants used their regular hair products, including creams, sprays, and oils, alongside heated tools. The researchers measured real-time emissions of VOCs, particularly cyclic volatile methyl siloxanes (cVMS), prevalent in many hair care items.

The mass spectrometry data revealed rapid shifts in the house's air composition, with cVMS accounting for the majority of detected VOCs. The emissions were influenced by factors such as the type of product, hair length, and the type and temperature of styling tools. Longer hair and higher temperatures resulted in higher VOC releases.

Hair Care Products' Effect on Indoor and Outdoor Air Quality

In light of the research, the scientists approximated that an individual's potential daily intake of one cVMS, specifically D5, could reach 20 mg. While the use of an exhaust fan mitigated pollutants post-styling, the researchers highlighted potential ramifications for outdoor air quality in densely populated regions, underscoring the imperative for extended studies on the human health consequences of siloxane exposure, primarily relying on animal studies.

Surveying hair care product usage patterns and assuming a 10% siloxane-based hair care product rate, the researchers projected total indoor-to-outdoor D5 emissions in the range of 0.4 to 6 tons annually in the US.

Nusrat Jung noted that exhaust fans and ventilation systems can disseminate these VOCs back into buildings, implying that individuals in urban environments could be impacted even if they don't use products with harmful chemicals.

While acknowledging limitations in modeling inhalation and indoor-to-outdoor emissions, the researchers highlighted variations in individual hair care practices and exposure based on indoor settings.

The team emphasized that remaining in the same room after hair styling could heighten VOC exposure. Consequently, they suggested promptly leaving the room after hair care routines or, ideally, avoiding the use of such products altogether to mitigate potential health and environmental effects.