Children, especially infants, are at significant risk of exposure to potentially toxic chemicals in dust while playing and crawling on the floor.
The multi-institutional team found a broad range of toxic chemicals from everyday products accumulated in household dust while analyzing compiled data from dust samples collected throughout the United States from multiple studies. They aimed to identify the top 10 toxic chemicals that are most commonly found in dust.
In the first-of-its-kind meta-analysis, published in Environmental Science & Technology, the researchers discovered that the number one chemical identified in household dust was DEHP, which belongs to a hazardous class of chemicals called phthalates that are used in everything from household cleaners to food packaging to cosmetics, fragrance, and personal-hygiene products.
Household dust was found to have phthalates in the highest concentration - with a mean of 7,682 nanograms per gram of dust - an amount that was several orders of magnitude above the other chemicals.
Phenols, chemicals used in cleaning products and other household items, were the second on the list of highest concentrations, followed by flame retardants and highly fluorinated chemicals that are used to make non-stick cookware.
"Our study is the first comprehensive analysis of consumer product chemicals found in household dust," says lead author Ami Zota, Sc.D., M.S., assistant professor of Environmental and Occupational Health at Milken Institute School of Public Health. "The findings suggest that people, and especially children, are exposed on a daily basis to multiple chemicals in dust that are linked to serious health problems," she adds.
Potentially toxic chemicals from consumer products are released into air and amalgamate with dust that settles on household furniture and the floor. Families are then exposed to the toxic dust composite through inhaling or ingesting small particles, while some minor amounts can be absorbed through skin.
Babies, infants, and young children are at a greater risk of chemical exposure because they crawl, play on dusty floors, put their hands in their mouths, and also mouth, suck, and chew on toys or items that could be lightly covered in dust.
From the dataset, Zota and team identified 45 potentially harmful chemicals in household dust that are used in products such as vinyl flooring, personal care and cleaning products, building materials, and home furnishings.
The authors point out that the research combines information from smaller dust studies and, as a result, offers solid conclusions with greater statistical power.
Several identified chemicals linked to cancer, developmental problems
Zota and colleagues uncovered that across multiple studies, 90 percent of dust samples contained 10 harmful chemicals including flame retardant TDCIPP - a known cancer-causing agent - often found in furniture, baby products, and other household items.
TCEP - a flame retardant added to couches, baby products, and electronics - was the chemical that had the highest estimated intake followed by the phthalates DEP, DEHP, BBzP, and DnBP. Intake of these chemicals could be underestimated, note the researchers, as these chemicals are also found in drug store products and fast food.
The four phthalates detected in dust are linked to several health hazards, such as interfering with hormones, and declining IQ and respiratory problems in children.
Other chemicals that are on the upper levels of the potential harm scale are highly fluorinated chemicals including PFOA and PFOS that are found in cell phones, pizza boxes, and non-stick, waterproof, and stain-resistant products. These chemical types have been associated with immune, digestive, developmental, and endocrine system health issues.
Many of the different chemicals found in household dust can lead to the same health risks, such as cancer or developmental and reproductive toxicity. These chemicals may be working together, and even small amounts of these chemicals in combination can amplify the associated health hazards, especially in developing children.
"The number and levels of toxic and untested chemicals that are likely in every one of our living rooms was shocking to me," says co-author Veena Singla, Ph.D., staff scientist at the Natural Resources Defense Council.
"Harmful chemicals used in everyday products and building materials result in widespread contamination of our homes - these dangerous chemicals should be replaced with safer alternatives."
Veena Singla, Ph.D.
Simple steps to reduce exposure to chemicals in household dust include using a strong vacuum with a HEPA filter, frequently washing hands, and avoiding all products that contain chemicals that are potentially harmful to health.
"Consumers have the power to make healthier choices and protect themselves from harmful chemicals in everyday products," says Robin Dodson, Sc.D., an environmental exposure scientist at Silent Spring Institute.
"These things can make a real difference not only in their health but also in shifting the market toward safer products," she concludes.