Toxic Emissions Fell in 2007, E.P.A. Says

WASHINGTON — The volume of toxic chemicals that were released into the environment or sent for disposal in 2007 dropped 5 percent compared with 2006, the Environmental Protection Agency said Thursday. But concealed within the overall numbers was good and bad news.

For example, the volume of released or disposed “persistent, bioaccumulative and toxic chemicals,” substances like lead, dioxin, mercury and PCBs, was up slightly, the agency said. Most of those releases were not to air or water, the agency said, meaning that the material was mostly buried in landfills, injected into deep wells or held in impoundments.

The number given for PCBs was up by 40 percent, but “it’s good news,” said Michael P. Flynn, acting deputy assistant administrator for the Environmental Protection Agency’s Office of Environmental Information.