Researchers explore possible link between factors of organic food consumption and electronic equipment ownership to levels of exposure to brominated flame-retardants. 

Body concentrations of a little-studied but widely used flame-retardant chemical appear to be related to lifestyle factors, with first-time mothers who favored organic foods showing lower levels of the chemicals in their breast milk, and those with more stereo and video items in their homes recording higher levels.

The findings, reported in a study by BU School of Public Health researchers, "do not negate the healthfulness and importance of breastfeeding, (but) rather highlight the importance of considering infant exposure in the management of organic pollutants" such as HBCDs, or hexabromocyclododecanes, the researchers said. The study was published in the journal Environmental Science & Technology.

The research team, headed by BUSPH's Department of Environmental Health, focused on certain brominated flame retardants that have not been widely studied, but have been called "a chemical of potential concern" by the US Environmental Protection Agency. The EPA has identified HBCD as bio-accumulative in living organisms and highly toxic to aquatic organisms, presenting human health concerns based on animal test results indicating potential reproductive, developmental, and neurological effects.

People may be exposed to HBCD from electronic products and dust. It is used as an additive in polystyrene foam for insulating buildings, and in the plastics housing for electronic equipment and appliances.

The study found that levels of HBCD in the mothers' breast milk were "significantly, positively associated" with the number of stereo and video electronics in the home -- a 17 percent increase per item. Separately, HBCD levels were lower for women who regularly chose organic foods, compared to those who did not.

Courtney Carignan, a doctoral candidate who conducted the study with faculty from the Department of Environmental Health, said the relationship between organic foods and HBCD levels was a surprise that has not been observed for other flame retardants.

"It could be that organic foods had lower levels of HBCD at that time, or eating organic foods could be related to some other lifestyle factor that is also related to HBCD exposure," she said.

She and environmental health Professor Thomas Webster noted that the study samples date to 2004-05, saying that HBCD levels may be higher today because of the phase-out of other flame retardants, known as PBDEs.

The researchers also cautioned that because study participants were all first-time mothers, "our findings might not be generalizable to the overall population." They suggested that future studies be conducted to examine chemical concentrations in dust, and also that the socioeconomic status of study participants and related lifestyle factors be considered.

A global phase-out of HBCD will be reviewed by the Stockholm Convention in 2013.The EPA has convened a multi-stakeholder group to explore the human health and environmental profiles of likely alternatives to HBCD.

Carignan said she had a personal interest in the study findings: She gave birth while conducting the research, and began to pay more attention to her infant's environment.

"It's something I think about a lot -- mobile infants and toddlers can ingest a lot of dust," she said. "Having this information caused me to change some of my personal habits. For example, I got rid of an old, unused VHS/DVD player and became more careful with my food choices."

Other authors of the study from the Department of Environmental Health included associate professors Michael McClean and Wendy Heiger-Bernays.

The study was supported by grants from the National Institute of Environmental Health Sciences.

Submitted by: Lisa Chedekel

chedekel@bu.edu