Scientists have found that methylsiloxanes — a lesser-known group of silicone-based chemicals used in everything from cosmetics to engine lubricants — are now creating widespread air pollution.

According to The Business Standard, a new study detected the compounds in cities, rural areas, coastal regions, and even forests, suggesting this form of pollution is far more common than previously understood.

What's happening?

Researchers from Utrecht University and University of Groningen published the findings in Atmospheric Chemistry and Physics after measuring unexpectedly high levels of airborne methylsiloxanes across parts of Europe and South America.

Methylsiloxanes are common ingredients in personal care products, industrial materials, household goods, and lubricating oils.

Scientists had long thought these chemicals mainly entered the atmosphere by evaporating from cosmetics and similar products. But the new study suggests vehicle and ship exhaust release larger methylsiloxanes. This happens because the compounds can survive extreme heat that the engines generate.

Researchers estimated that methylsiloxanes account for roughly 2% to 4.3% of organic aerosols in the atmosphere, making them among the most common synthetic materials found in air pollution.

The study also found atmospheric concentrations appeared to be more than 1,000 times higher than levels of PFAS, or "forever chemicals."

Researchers detected the highest readings in heavily polluted urban areas such as São Paulo, Brazil, while the lowest concentrations appeared in forested regions of Lithuania.

Lead researcher Rupert Holzinger said atmospheric concentrations were higher than expected.

Why are methylsiloxanes concerning?

One of the biggest concerns is that people may be inhaling methylsiloxanes constantly without scientists fully understanding the long-term health effects.

Holzinger said daily exposure could already exceed exposure to other synthetic pollutants such as PFAS and microplastics, yet little is known about what breathing in these compounds over months or years could mean for human health.

That makes this more than just an air quality issue. When researchers identify a pollutant that is widespread, persistent, and poorly understood, it raises concerns for regulators, doctors, and families alike.

The findings also highlight how modern air pollution extends far beyond soot or smog. Airborne contaminants can include synthetic chemicals tied to consumer products and transportation systems that receive far less public attention.

Because methylsiloxanes are chemically stable and capable of traveling long distances, researchers said the compounds may spread far beyond areas with heavy traffic.

Methylsiloxanes could even affect how other air pollution interacts with clouds and ice in the atmosphere. The pollution may influence broader environmental processes in ways scientists are only beginning to study.

Vehicle emissions may account for more than half of the pollution identified in the study, pointing to a major source embedded in everyday transportation systems.

What's being done about methylsiloxanes?

For now, researchers say more study is urgently needed to determine how much people are inhaling, how long the chemicals remain in the environment, and what long-term exposure may do to human health.

The findings could also prompt regulators to examine how methylsiloxanes are used in consumer products and industrial applications more closely.

Reducing tailpipe pollution may help as well. Expanding public transit, strengthening shipping emissions standards, and accelerating the shift toward lower-emission transportation could reduce one major pathway for these chemicals to enter the atmosphere.

Get TCD's free newsletters for easy tips, smart advice, and a chance to earn $5,000 toward home upgrades. To see more stories like this one, change your Google preferences here.