Posted on Jul 13, 2017, 8 a.m.
Endocrine-disrupting chemicals in house dust can spur fat cells to accumulate more triglycerides or fat.
There is no question that an unhealthy diet combined with minimal physical activity is largely responsible for the global obesity epidemic. However, researchers have now pinpointed specific environmental pollutants that also might play a major part in the obesity problem. A research team recently reported that minor amounts of household dust rife with such pollutants can cause fat cells to build up triglycerides (fat). They observed such buildup in a lab dish yet it is believed that the results are applicable to human beings who reside in living spaces with even a moderate amount of dust. The authors of the study recognize that funding from the Duke Cancer Institute, Fred and Alice Stanback and the National Institute of Environmental Health Sciences was provided.
A Look at Endocrine-Disrupting Chemicals (EDCs)
EDC is an acronym that stands for endocrine-disrupting chemicals. These are naturally occurring or synthetic compounds that have the potential to interfere or copy the human body's hormones. EDCs like flame retardants, bisphenol-A and phthalates are known for potential effects on the human body's immune, neurological and reproductive functions. Animal studies indicate exposure to certain EDCs early in life can spur weight gain in later years. This is why such EDCs are now being referred to as obesogens.
Some product manufacturers have decreased the amount of EDCs in their offerings. However, many EDCs are still widely present across all sorts of consumer goods. These EDCs end up reaching indoor dust where they are subsequently inhaled, ingested and even absorbed directly through the skin. According to the United States Environmental Protection Agency, children consume upwards of 50 milligrams of household dust every single day. Researcher Heather Stapleton is concerned about the effects of EDCs. It is possible EDCs affect fat cells and increase the chances for obesity. EDC exposure even spurs a number of other problems the scientific community has not yet identified.
About the Research
Stapleton's research team gathered indoor dust samples across nearly a dozen homes throughout North Carolina. They tested extracts from these samples with a mouse pre-adipocyte cell model commonly used to test compounds for effects on the buildup of triglycerides (fat). Extracts from seven of the eleven dust samples spurred the pre-adipocytes to become mature fat cells and collect triglycerides. Extracts from the samples caused the cells to divide, forming a bigger precursor fat cell pool.
Merely one of the dust samples had no effect. Among the 44 most common household dust contaminants tested in the model, the pesticide pyraclostrobin, the plasticizer DBP, and the flame retardant TBPDP generated the most robust fat-producing effects. This finding makes researchers think the mixture of such chemicals in household dust spurs the buildup of triglycerides along with fat cells.
Accumulations of dust as low as three micrograms in quantity produced measurable effects. This level is far below the amount of dust the typical child is exposed to on a daily basis. The research team suggests that the dust found in households is likely to be a source of chemical exposure that has the potential to disturb metabolic health. Such disruptions are especially common in children.
Christopher D. Kassotis, Kate Hoffman, Heather M. Stapleton. Characterization of Adipogenic Activity of House Dust Extracts and Semi-Volatile Indoor Contaminants in 3T3-L1 Cells. Environmental Science & Technology, 2017; DOI: 10.1021/acs.est.7b01788