Warning: This article may trigger an intense desire to obsessively clean your residence.
Overeating, sedentary lifestyles, lack of exercise…these are known contributors to the world’s obesity epidemic.
But a new study suggests a common household annoyance may play an unexpected role: dust.
Small amounts of house dust containing common environmental pollutants can spur fat cells to accumulate more triglycerides, or fat, in a lab dish, researchers at Duke University found.
The study was funded by the National Institute of Environmental Health in the US, and was published in the peer-reviewed journal Environmental Science and Technology.
The implicated pollutants are known as endocrine-disrupting chemicals (EDCs). They are synthetic or naturally occurring compounds that can interfere with or mimic the body’s hormones. EDCs, such as flame retardants, phthalates, and bisphenol-A, are known for their potential effects on reproductive, neurological, and immune functions.
But animal studies also suggest that early life exposure to some EDCs – known as “obesogens” – can cause weight gain later in life.
Some manufacturers have reduced the use of EDCs in products, but many are still ubiquitous in consumer goods. They wind up in indoor dust that can be inhaled, ingested, or absorbed through the skin.
The U.S. Environmental Protection Agency estimates that children consume 50 milligrams of house dust each day. Concerned about the potential effects EDCs in dust might have on children’s health, the researchers wanted to see if the compounds in house dust might have an effect on fat cells.
They took samples of indoor dust from 11 homes in North Carolina, and tested extracts from those samples in a mouse pre-adipocyte cell model.
According to the researchers, extracts from seven of the samples triggered the cells to develop mature fat cells and accumulate fat. Extracts from nine samples spurred the cells to divide, creating a bigger pool of precursor fat cells. Only one sample showed no effects. The researchers concluded that house dust is a likely source of chemicals that may disrupt metabolic health, particularly in children.
In a press release, the American Chemical Society elaborates:
Additionally, among the 44 individual common house dust contaminants tested in this model, pyraclostrobin (a pesticide), the flame-retardant TBPDP, and DBP, a commonly used plasticizer, had the strongest fat-producing effects. This suggests that the mixture of these chemicals in house dust is promoting the accumulation of triglycerides and fat cells, the researchers say. Amounts of dust as low as 3 micrograms — well below the mass of dust that children are exposed to daily — caused measurable effects.
Head researcher Dr. Heather Stapleton said of the findings,
“What our study demonstrates is that exposure to mixtures of chemicals found in our home can change the metabolic function of our cells.
“At this point it’s difficult to provide advice on how to avoid exposure…cleaning more with wet techniques (e.g. mopping) can help remove and reduce dust particles […] dry dusting can sometimes release more dust particles to the air which can then be inhaled.”
If this study inspires you to scrub down every surface and vacuum every corner of your home, that’s not necessarily a bad thing. Most of us could use a bit (okay, a LOT) more exercise.
But keep in mind that this study is very small, and it didn’t look at whether those whose homes are dustier than others are exposed to more chemicals. And, we don’t know if the effects on the mouse cells would be seen in human cells.
The study does, however, build on previous research, also led by Dr. Stapleton. And, other studies on the relationship between endocrine disruptors and obesity have yielded similar findings – some referring to obesogens as an emerging threat to public health.