EPA has already revamped its guidelines somewhat, following a preliminary review of the Maine test, and the agency says it will conduct a further review of the state work and conduct its own CFL exposure tests before determining what further action to take. The Maine Department of Environmental Protection (DEP) Feb. 25 released revised guidelines, contained in a report detailing its mercury exposure test results, which found high mercury levels could occur from the breakage of a single light bulb.

The issue of mercury in CFLs is a growing concern as the bulbs continue to be heavily promoted because of their energy efficiency, yet they pose a health hazard if they are broken or not properly disposed. The new Maine guidelines go well beyond any prior guidance by suggesting that households with infants, small children and pregnant women consider not using the bulbs "in situations where they could be easily broken" because of possible mercury exposure through breakage.

They also suggest that homeowners "consider removal of the area of carpet where the breakage occurred as a precaution," particularly if the breakage occurred in an area where infants or children play on the floor. EPA says an initial review of Maine's study on mercury exposure prompted the agency to update its own recommendations for dealing with broken CFLs, including the addition of explicit instructions for different types of flooring along with the recommendation that the broken bulb be placed in a glass jar with a metal lid.

Previous EPA recommendations included only putting the debris in a sealed plastic bag, an approach Maine found did little to control mercury, as well as wiping the area with a damp paper towel and opening a window if weather permits. But EPA's revised guidelines do not suggest that anyone curtail use of the bulbs over breakage concerns.

An EPA spokeswoman says that pending completion of a full review of the study, "EPA will determine whether additional changes to the cleanup recommendations are warranted. The Agency plans to conduct its own study on CFLs after thorough review of the Maine study." The revised Maine guidelines are contained in a broad report, Maine Compact Fluorescent Light Study, that analyzes mercury released in 45 experimental trails involving different types of bulbs and flooring. "The most notable finding of the study was how variable the results can be depending on the type of lamp, level of ventilation and cleanup method," the report says.

The study did find high exposure levels in some cases, noting that mercury concentrations released from CFL bulbs often exceed the state's ambient air guideline of 300 nanograms per cubic meter (ng/m3) for a period of time, with readings as high as 100,000 ng/m3 from the breakage of a single bulb and that flooring surfaces, even after they are cleaned, can continue to emit mercury at greater than 50,000 ng/m3. The study also found that the best container to place broken CFLs is a glass jar with a sealable lid, whereas "double re-sealed polyethylene bags…did not appear to retard the migration of mercury adequately," EPA's revised guidelines advise the glass jar or the bag.

A Maine DEP source says the state still recommends use of CFLs with the caution that "people need to be very careful with them, just like they are with bleach and sharp knives."

(By: Dawn Reeves- Superfund Report- 3/10/08)