China will seek binding pollution targets for developed countries and reject similar requirements for itself at an international climate summit next month, China’s top climate envoy said Wednesday.

Nearly half of lakes and reservoirs nationwide contain fish with potentially harmful levels of the toxic metal mercury, according to a federal study released Tuesday.

If you walk onto the Mayo Bridge by Shockoe Slip and drop a line on the downstream side, you essentially are fishing in the Chesapeake Bay. If you dump pollution in the Shenandoah River, beyond the Blue Ridge Mountains, you can hurt the bay. As we try to restore the Chesapeake, it helps to ask: Where is the bay, and what are we trying to restore?

Recent tests found high levels of toxic chemicals called PCBs in the James River and some tributaries between Richmond and Hopewell. In some cases, levels of the chemicals were hundreds of times higher than the state limit, state officials said. The PCBs pose a threat to fish but not people, unless people eat contaminated fish, said Bill Hayden, a spokesman for the state Department of Environmental Quality.

For the first time in nearly 30 years, the Environmental Protection Agency plans to limit the quantity of toxic metals that coal-fired power plants release into U.S. waterways.

More than 500 villagers in central China have been found to have high concentrations of a dangerous metal in their bodies after a series of leaks from a chemical plant, state media reported Monday.

Virginia regulators want to reduce the amount of PCBs in the Staunton River by 96 percent.

July is prime time for smog, but so far the region has suffered no dirty days. “I can’t recall a summer this clean,“ said Dan Salkovitz, a meteorologist with the state Department of Environmental Quality. Ozone, the main pollutant in smog, typically hits unhealthful levels 20 days or so during the warm months. The region had 17 dirty-air days last year—14 by July 28. There were 25 smoggy days in 2007.

Gov. Timothy M. Kaine announced plans to conduct the pollution checks for plants and factories built before the federal Clean Air Act in 1970.

Charlottesville and Albemarle County residents who see signs of pollution in area waterways now can report it through a hot line. The water-pollution hot line was set up by area localities and agencies to meet the requirements of their federal stormwater permits. The Rivanna Regional Stormwater Education Partnership is made up of Charlottesville, Albemarle, the University of Virginia, Piedmont Virginia Community College, the Rivanna Water and Sewer Authority and the Virginia Department of Transportation, which manage the storm drain systems in the region. The hot line is part of the group’s outreach under its Illicit Discharge Detection and Elimination program, which is required for them to hold stormwater permits.

Toxic emissions continue to decline in Virginia. Factories, power plants and other industries released 63 million pounds of the troublesome chemicals in 2007, a 4 percent drop from the year before, a new report says. The state Department of Environmental Quality disclosed the figures yesterday in its annual report on toxic emissions. “We have seen a few years where the numbers were higher, but overall the trend is down, and that’s exactly what we like to see,“ said DEQ spokesman Bill Hayden.

Bay health gets another bad rating As growth outpaces cleanup, Chesapeake is put at 38 percent The health of the ailing Chesapeake Bay has shown no improvement in the past year as pollution caused by population growth and development overwhelms cleanup efforts, according to a report released yesterday. The annual study by the Chesapeake Bay Program—the federal-state partnership working on bay restoration—said the nation’s largest estuary remains “severely degraded” because of contaminants such as nitrogen and phosphorous.

The James River is now clean enough for swimming in a 13-mile stretch that includes the popular Pony Pasture Rapids in South Richmond. State environmental officials revealed the good news yesterday during a meeting to discuss a planned cleanup of a still-polluted part of the James. Water tests during the past several years showed that fecal bacteria had dropped to acceptable levels from near the Chesterfield County-Powhatan County line to the Boulevard Bridge in Richmond.

The Maryland Department of the Environment says most of the potentially toxic coal ash sludge that spilled from a ruptured pipeline near Luke missed the Potomac River.

State environmental officials will hold two meetings today to discuss a plan they are developing to reduce bacteria levels in the James River in the Richmond area. Fecal bacteria get in the James from sources including animals and sewage overflows. Swimmers and others who swallow water contaminated with fecal bacteria can get upset stomachs and diarrhea.