The Pew Charitable Trusts

Americans might have been exposed to a higher level of toxic chemicals and chemical compounds in 1999 than they were the year before, according to new Environmental Protection Agency (EPA) data.

The nation's industries generated 7.77 billion pounds of toxic chemicals and compounds in 1999, a 5.3 percent jump from 1998 due mainly to significant increases in emissions and solid waste disposals from metal mining facilities in the West. More modest increases from coal and oil-powered electric utilities in eastern states also contributed to the overall rise.

EPA tracks toxic chemical releases and industrial waste management practices in an annual report mandated by the 1986 Community Right-To-Know Act. The law requires facilities with more than 10 full-time employees handling more than 10,000 pounds of any listed chemical to report the quantity of each chemical released into the air, land or water to the states and the federal government.

Three years ago, EPA added mining operations, electric utilities and other chemical and petroleum product handlers to the monitoring list. While releases from manufacturers continue to decline, dropping 2.5 between 1998 and 1999, releases from the newcomers reversed the downward trend.

Metal mining accounts for more than half of the nation's toxic releases, the report shows. Mining operations in Nevada, Utah, Arizona, Alaska and New Mexico led the list of polluters, spewing more than 3.7 billion pounds of toxic substances into the environment.

Copper compounds released from metal mining operations alone accounted for more than 1.7 billion pounds of the total amount. The Kennecott Utah Copper Mine, owned by British-based Rio Tinto Ltd. and located roughly 20 miles southwest of Salt Lake City, was the largest single source of toxic discharges with more than one billion pounds of on-site and off-site releases, TRI data shows.

EPA defines toxic substances as "materials that [can] cause death, disease, or birth defects in organisms that ingest or absorb them."

"The TRI program and the information that mines provide us are a starting point for determining whether or not there's a threat to human health," says Joyel Dhieux, an environmental official in EPA Region 8, which includes Utah and New Mexico.

Dhieux said it is "too soon to tell" whether the new data warrants further regulatory action against polluters in her region, but she pointed out that release of 1998 data last year drew attention to potentially dangerous mercury releases from metal mining operations in neighboring Nevada, which is part of EPA Region 9.

Threats to public health from lead were the driving force behind the Bush administration's announcement last week that it would proceed with a new Clinton-era rule reducing the 10,000 pound reporting threshold for the metal to 100 pounds. The change will require thousands of additional businesses to report lead discharges starting this year.