Brian Nearing in the Albany Times-Union reports that Texas Republican congressman John Carter is pushing a little-known congressional maneuver to block rules by the U.S. Environmental Protection Agency that would impose mercury limits for the first time ever on cement kilns, including Ravena's Lafarge plant. Science has long proved mercury is a potent neurotoxin. Earlier in the month, a preliminary study by the Harvard School of Public Health of about 185 people who live in the vicinity of the Lafarge plant found that one adult in 10 and one child in 20 had mercury in their blood at levels elevated enough to warrant a visit to the doctor.