— Ten days after a massive spill of coal ash into the Dan River in Rockingham County, state health officials on Wednesday warned people against swimming in the river or eating fish from it.

Duke Energy has estimated up to 82,000 tons of ash spilled from two ponds at a defunct coal-fired plant in Eden after a stormwater pipe that ran under the ponds ruptured on Feb. 2. The Charlotte-based utility closed the plant two years ago.

The ash, which is left over after coal is burned to power electric plants, contains arsenic, mercury, lead, boron and other heavy metals. Scientists say the contaminants don't readily dissolve in water and usually sink to the bottom of the river, where they can pose a risk to aquatic life.

State environmental officials initially said their tests of water downstream of the spill showed only elevated levels of copper in the river. They later said, however, that they misread the test results and said the level of arsenic in the river also exceeded safe levels.

On Wednesday, the state Department of Environment and Natural Resources reported that arsenic and copper levels in the river had dropped to safe levels but that the levels of aluminum and iron in the river remained above surface water quality standards.

"We remain very concerned about the effects of this spill on the river’s long-term health," Tom Reeder, director of the state Division of Water Resources, said in a statement.

Meanwhile, the state Division of Public Health issued two health advisories for the Dan River near the spill and downstream.

Health officials warned against "recreational contact" with the river or sediment, including contacting any ash that washed up along the river banks. Because contact with the ash can cause skin irritation, people should wash exposed areas with soap and water, officials said.

Also, people should avoid eating fish or shellfish from the river downstream of the spill, they said.