Regularly washing your hands and cleaning the house may reduce the amount of exposure you have to common toxic household chemicals, finds a new study out of Columbia University’s Mailman School of Public Health.

The study, published in the Journal of Exposure Science and Environmental Epidemiology, is the first of its kind to assess the effects of hand washing and house cleaning in connection to organophosphate flame retardants, or OPFRS, common toxic household chemicals found in everything from furniture upholstery to electronics. OPFRs can directly transfer to the dust that settles on these products and from there — everywhere. High levels of OPFRs have been found in human bodies, water bodies, and even in food.

OPFRs became a standard part of our environment around 2005, when many industries around the world swapped them in to replace the in-vogue flame retardant polybrominated diphenyl ethers, or PBDEs, which had been linked to a host of serious health problems and had been found “in everything from breast milk to household dust,” according to one investigative report in the science magazine Undark.

Now, history seems to be repeating itself. While OPFRs affect the body differently than PBDEs, they appear to be just as pervasive. And there are early signs OPFRs may be related to endocrine disruption, decreased fertility, and thyroid dysfunction in humans. Per the Undark report:

“We know everyone is exposed to organophosphate flame retardants,” said Heather Stapleton, a Duke University professor, who has been studying flame retardant chemicals for more than a decade. “We know children have higher exposure than adults, and that exposure is higher than it was for PBDEs.”

The latest research from the Mailman School focused on exposure to a common flame retardant called Tris, as well as six other similar chemicals. The team sought to validate or contest advice from the US’s Environmental Protection Agency, which holds the best way to reduce exposure to these chemicals is to regularly wash hands and clean with moist cloths, wet mops and vacuuming.

It was a tiny and simple study. Thirty-two women participated in one of two interventions – house cleaning or hand washing. Women in the house cleaning group were given microfiber mops, vacuums and microfiber cloths, and were asked to increase the amount of house cleaning they did for a week. The hand washing group was provided with hand soap and asked to regularly wash their hands, more often than they normally do, especially before having meals. In the second week, both groups were asked to perform both activities — extra hand washing and house cleaning. Researchers also asked participants for urine samples in the beginning of the study and at the end of the first and second weeks of the study.

The urine tests conducted at the start of the study yielded 97% samples positive with Tris. After the first week of hand washing or house cleaning, the groups’ urine tests revealed a 47% and 31% decrease in Tris respectively. Women who had a higher-than-average exposure to the chemical in the first test, showed a significant 74% drop after a week of either hand washing or house cleaning. After the second week, when participants both washed hands and cleaned house regularly, their Tris levels fell from their starting tests by similar margins, suggesting that either washing hands or cleaning house regularly is as effective as doing both, supporting the EPA’s guidelines.

“However, none of the reported flame retardants were reduced below the limit of detection, indicating that individual behavior cannot entirely reduce exposure,” says Elizabeth A. Gibson, the study’s first author and PhD student in the department of environmental health sciences at Columbia’s Mailman School.

The researchers intend to study OPFRs further to better understand the health repercussions of being regularly exposed to these toxic household chemicals. Until they know for sure, best to give your hands (and plates) an extra rinse before your next meal — assuming you’ve detoxed your home cleaning products.