Skip to main content

Bucknell Chemist’s Study Finds Health Hazard from Common Cleaners

LEWISBURG, Pa. –– We all have household cleaners to clean and sanitize surfaces inside our home, and most of the time they include both bleach-based and citrus-scented varieties. But according to new research by Bucknell University chemistry professor Doug Collins and University of Toronto researchers, mixing the two can become toxic under the right circumstances. Bleach fumes, in combination with light and a citrus scent found in many household products, can form airborne particles that might be harmful when inhaled by people or pets.

The researchers published their study recently in American Chemical Society (ACS) journal Environmental Science & Technology.

Bleach cleaning products emit chlorine-containing compounds that can accumulate to relatively high levels in poorly ventilated indoor environments. These gases can react with other chemicals commonly found in homes, such as limonene –– an orange- or lemon-scented compound added to many personal care products, cleaners and air fresheners. The researchers found that when these gases are combined with indoor lighting or sunshine through windows, they form airborne particles. Separate research shows that airborne pollutant particles such as these may travel deep into our lungs, causing short-term health effects such as eye, nose and throat irritation; coughing; sneezing; and shortness of breath. They also may be associated with more chronic health conditions like asthma.

“The key is the combination of the bleach fumes and citrus compounds with the indoor light — that’s what causes the pollutant particles to form,” Collins said. “We know that airborne particles similar to the ones produced in this reaction can be associated with various negative health outcomes.” 

Just how hazardous remains to be seen, and the researchers conclude that the risks need to be studied further. But they warn that the pollutants could be occupational hazards for people involved in cleaning activities and possibly for pets.

For that reason, Collins advises ventilating the area with fresh air when using these products indoors.

“You should open your windows and turn on your fan to vent the contaminated air outside and replace it with clean, fresh air,” he said. 

Collins and the six Bucknell students who work in his research lab are continuing to study indoor air pollutants.

“There are a lot of ways to clean your home, so being informed on these types of reactions and consequences for indoor air quality may be beneficial to your health,” he said.


CONTACTS: Collins, 570-577-3683,; Mike Ferlazzo, 570-577-3212, 570-238-6266 (c),

Comments are closed.