Buildup of Newer Flame Retardants Concerns Scientists

Increasing concentrations of two newer generation flame-retardant chemicals were detected in atmospheric samples collected in the Great Lakes region between 2008 and 2010, a new study indicates.

The chemicals are used to reduce flammability in various products, including electronic devices, textiles, plastics, coatings and polyurethane foams. They are 2-ethylhexyl tetrabromobenzoate [TBB] and bis(2-ethylhexyl) tetrabromophthalate [TBPH].

TBB and TBPH are included in commercial mixtures introduced in recent years to replace polybrominated diphenyl ethers (PBDEs), widely used flame retardants taken off the market because they can leak from products into the environment.

In this study, Indiana University researchers analyzed 507 air samples collected at six locations on the shores of the Great Lakes.

"We find that the environmental concentrations of (TBB and TBPH) are increasing rather rapidly," Professor Ronald Hites, of the School of Public and Environmental Affairs, said in a university news release. "It's rare to find that concentrations of any compound are doubling within a year or two, which is what we're seeing with TBB and TBPH."

The highest concentrations were detected in urban areas, including Cleveland and Chicago. But the chemicals were also present in about half the samples from remote locations in Michigan, New York and Ontario, Canada.

The findings, published in the journal Environmental Science & Technology, suggest that these newer-generation flame retardants may be replacing their predecessors in the environment, the researchers said.

Previous research has found TBB and TBPH in household dust and furniture foam in the United States, marine mammals in Hong Kong and sewage sludge in California.