- When bleach fumes mix with a citrus compound found in many household cleaners, they can form ultrafine particles like those found in smog.
- This compound is called limonene and is usually relatively mild but in large amounts can irritate the eyes, throat, lungs and skin.
- Some green products may be safer than traditional bleach, but some experts say using vinegar and baking soda can also be non-toxic way to clean your home.
The smell of bleach has long been associated with a clean home, especially during cold and flu season.
But a group of researchers learned that when bleach fumes mix with a citrus compound found in many household cleaners, it can create potentially harmful airborne particles — for you and your pets.
This citrus compound is known as limonene. It is found in thousands of cleaning products, personal care products, and air fresheners, and is also released from certain wood products.
By itself, limonene is not very toxic, although exposure to larger amounts can irritate the skin, eyes, throat and lungs. In the presence of air, it can oxidize to form compounds that cause skin allergy.
Limonene is also one of the most common volatile organic compounds (VOCs) found indoors, write the authors of the new study.
VOCs are gases emitted by many household products and can impact indoor air quality. Once released, they can linger in the air or stick to surfaces.
Because bleach and products containing limonene are often used in the same indoor spaces, researchers from the University of Toronto and Bucknell University in Pennsylvania looked at what happened when these chemicals combined.
The researchers write that during and after the use of bleach-based cleaners, high amounts of hypochlorous acid and chlorine gases can quickly build up in poorly ventilated indoor environments.
The study was published October 2 in Environmental Science and Technology.
They simulated this effect using an environmental chamber, to which they added limonene and the gases formed from bleach.
Upon exposure to fluorescent light or sunlight, these compounds reacted to form secondary organic aerosols (SOAs). The initial reactions occurred even in the dark, with SOAs forming when the chamber was exposed to light.
SOAs are fine particles that are also a major component of smog. When particles are small enough, they can travel deep into the lungs and cause short-term effects such as coughing and shortness of breath. Very fine particles can also enter the bloodstream through the lungs.
Regular exposure to particulate matter is linked to health problems such as heart attacks and breathing difficulties. People with existing heart disease, asthma, or other lung conditions are at greater risk.
Md. Aynul Bari, an assistant professor in the Department of Environmental & Sustainable Engineering at the University at Albany, State University of New York, said these results show the “potential impacts of household bleach cleaning products on indoor air quality.”
Bleach used for cleaning may pose other health risks.
“It is known that the use of chlorine bleach-containing products in cleaning activities such as laundry and dish washing, can release volatile organic compounds — such as chloroform and carbon tetrachloride — which may pose a carcinogenic risk to public health,” said Bari.
Chloroform is a “probable carcinogen” in humans, while carbon tetrachloride is a “possible carcinogen.”
Bari added that more research is needed to “better understand the health effects of these particles.”
So how can you clean your home and still protect your health?
Bari said if you use bleach or scented cleaning products, do so only in well-ventilated environments “in order to minimize your inhalation exposure.”
Also, if you use bleach-containing products, he suggests choosing plain bleach instead of products with added fragrances or surfactants.
Using “green” cleaning products may also reduce your exposure to chemicals, including VOCs.
However, you have choose products carefully. Those with added fragrance chemicals — such as limonene and other terpenes — can form secondary pollutants, including ultrafine particles.
“A comparative analysis of volatile emissions from green and conventional fragranced products, including cleaning products and air fresheners, found over 550 VOCs emitted from 37 products, with nearly 25 percent classified as toxic or hazardous under US federal laws,” writes Anne Steinemann, a professor of civil engineering at the University of Melbourne in Australia, in the journal Building and Environment.
In its Guide to Healthy Cleaning, the nonprofit Environmental Working Group recommends choosing cleaning products free of fragrance, ammonia, and bleach.
It also suggests looking for products certified by Green Seal or Ecologo.
You can also choose a simple cleaner like vinegar and water or baking soda.