By now, you likely know the buzz on compact fluorescent light bulbs: They use 75 percent less energy and can last more than five times longer than incandescent bulbs. The energy savingsand potential reduction in greenhouse gas emissionshave prompted several state and local governments, including North Carolina, to consider phasing out the sale of incandescents over the next decade. (Introduced last year, House Bill 838 would study the feasibility of banning conventional light bulbs in 2016.)

The buzzkill is that mercury levels in CFLs pose health and environmental dangers when the bulbs are broken or thrown in the trash. Mercury contains neurotoxins that are harmful, especially to pregnant women and children. (And to think in junior high science class we entertained ourselves by slicing and dicing blobs of quicksilver on our desks.)

All is not lost, though. The Environmental Working Group, a Washington, D.C.-based nonprofit group, researched CFLs and found that some have lower levels of mercury than others. In its Green Lighting Guide, the EWG identifies seven models made by Earthmate Litetronics, Sylvania, Felt, MaxLite and Philips that contain just 1 milligram to 2.7 milligrams of mercury per bulb. Mercury levels in other CFLs can range from 4 to 6 milligrams.

Don’t be misled by what appears to be low wattage in the low-mercury bulbs. A 14-watt CFL emits as much light as a 60-watt incandescent. A 23-watt CFL is equivalent to a 100-watt incandescent: All of the light, but less of the mercury.

However, even low levels of mercury shouldn’t be dumped in conventional landfills. In the Triangle, dispose of your CFLs with batteries and other hazardous household waste at county drop-off centers: Durham County, 1900 E. Club Blvd.; Wake County, 9037 Deponie Drive in Raleigh and 6300 Old Smithfield Road in Apex; Orange County, Eubanks Road west of N.C. 86; and Chatham County, west of Pittsboro off U.S. 64 on County Landfill Road.

Read the EWG’s Green Lighting Guide, including tips on how to clean up a broken CFL bulb, at