DuPont has discovered evidence of elevated cancer rates among employees at its Washington Works plant near Parkersburg.

That's according to a story Sunday by The Associated Press, which quotes government records.

According to the records... DuPont says it doesn't know why there may be a fivefold increase in certain cancers for employees at the plant.

While it's information DuPont says it has regularly reported to the Environmental Protection Agency since 2006, it's the first time it's been known publicly.

And DuPont says it has no knowledge it's related to the on-going issue of the effects of C-8 on plant employees and the public.

"Not only do we have no reason to believe it's associated with C-8," says Washington Works Manager Bill Hopkins, "we have no reason to believe it's associated with any other chemicals. There's nothing to indicate any connection with any type of chemical, but we're going to look to see if there's any common threads."

Hopkins also noted Monday the cancer study involves other DuPont plants, not just Washington Works. He adds that, while the numbers are higher, it still involves a small percentage of his plant's total workforce.

DuPont epidemiologist Morel Symons told the A.P. Monday the study he hopes to start this summer is designed to find out whether anything at the plants is causing carcinoid tumors.

Symons says early work on the problem suggests there are more cases than would be expected at the plant.