Cleaning products cause indoor pollution levels similar to a busy road

Fragrant chemicals in scented surface cleaners react with ozone to produce pollutant particles that may be harmful to the respiratory system

By Carissa Wong

Scented surface cleaning products can expose you to a similar amount of pollutant particles as a busy urban road used by 28,000 vehicles a day. The findings suggest that professional cleaners may be especially at risk of harm caused by indoor pollutants.

Surface cleaning products often contain fragrant chemicals called monoterpenes that smell like citrus or pine. Monoterpenes easily evaporate into the air where they react with unstable molecules such as ozone to produce pollutant particles called secondary organic aerosols (SOAs).

SOAs – which are also generated by vehicle fumes – can irritate your airways. “The smaller the particles are, the deeper they go into the lung,” says Colleen Rosales at Indiana University. “Smaller particles cause serious respiratory problems, such as inflammation. They can also introduce chemicals into the bloodstream.”

Rosales and her colleagues cleaned the floor of an office room for 15 minutes using a mop soaked in a scented commercial cleaning product and repeated this a few hours later. The team used particle counters to track the levels of small SOAs – with a diameter of 10 nanometres or less – in the air during and after cleaning.

By modelling how particles enter the respiratory system, they calculated that being in a room during 1.5 hours of mopping would expose the lungs to similar pollutant particle levels as spending 1.5 to 6 hours by a busy road. This comparison was based on previously published pollution data from a road used by thousands of vehicles a day and lined by multistorey buildings.

More research is needed to establish the health effects of these indoor pollutants, the team says.

“We are currently lacking detailed information on how the toxicity of indoor particles compares to those generated through vehicles outdoors. What would be good to know is which are more harmful to health,” says Nicola Carslaw at the University of York in the UK. If they are harmful, we may want to think about developing guidelines to lower the health risks for professional cleaners, she adds.

Rosales suggests that SOA levels indoors can be reduced by using fans containing filters that capture ozone and the pollutants. People can also avoid products that contain monoterpenes.

Journal reference: Science Advances, DOI: 10.1126/sciadv.abj9156