Key TakeawaysScented cleaning products can create indoor air pollutionFragrances in conventional and botanical cleaners can react with ozone and form ultrafine nanoparticlesReducing fragrance and improving ventilation can lower exposure.THURSDAY, Aug. 27, 2026 (HealthDay News) — The citrus, pine or floral scent of a freshly cleaned room may come with something unexpected: invisible air pollution.A new study warns fragrances in both conventional and botanical cleaning products can react with ozone in indoor air, forming nanoparticles that can travel deep into the lungs if inhaled.In a model home, researchers found that mopping floors, spraying counters and wiping surfaces with scented products generated billions or even trillions of these ultrafine particles.They say the respiratory dose can be comparable to — or even greater than — standing outside along a busy road."Importantly, cleaning removes viruses and bacteria from surfaces, but it can also generate invisible air pollution," said lead author Brandon Boor, a professor of civil engineering at Purdue University in West Lafayette, Indiana. "There's no visible dust or smoke in the air, but these particles are forming."Researchers warn particles this small can contribute to respiratory irritation and inflammation or potentially enter the bloodstream.To reduce exposure, they recommend choosing low-fragrance or fragrance-free products, using fewer scented products at once, and opening windows or running exhaust fans.The findings are being presented today in Chicago at a meeting of the American Chemical Society. Findings presented at medical meetings are considered preliminary until published in a peer-reviewed journal.More informationNASA has more on air pollution.SOURCE: HealthDay TV, Aug. 27, 2026 .What This Means For YouWhen you use scented cleaning products, you may create invisible air pollution that can harm your lungs, so choose fragrance-free products and improve ventilation to reduce your exposure..Sign up for our weekly HealthDay newsletter