OAKLAND — The company that owns Messalonskee Dam faces possible state penalties after an employee was caught spraying a toxic weed killer in and around Messalonskee Lake.

The amount of the herbicide Durazone sprayed Aug. 3 by an employee of Exxex Hydro Associates, the parent company of Messalonskee Stream Hydro, was small, according to Maine’s Board of Pesticides Control. Durazone in large amounts can affect humans and animals.

Henry Jennings, the board’s director, said the tiny amounts of toxin detected after the spraying were unlikely to pose environmental consequences. He said the net effect was putting a half-ounce of herbicide into the lake.

Durazone, sold by Bayer, kills a wide variety of plants. Its label warns it’s toxic to plants, fish and other aquatic animals. The National Pesticide Information Center says prolonged or extreme exposure can cause severe health effects in humans, from shedding fingernails to spontaneous late-term abortions.

“We’re confident that some enforcement is appropriate, but we haven’t arrived at exactly what that would be,” Jennings said. “Clearly education is a part of it. The company needs to have a better understanding of the applicable laws.”

Jennings said Essex Hydro Associates is cooperating and the incident appears to be isolated. It could take months to decide what penalties might be imposed, he said.

Oakland resident Ed Pearl, a former director of Friends of Messalonskee Lake, was driving by the dam when he saw the man spraying Durazone on plants growing in spillway boards used to impound water on the north end of the lake. He confronted the man and later filed a complaint with the state board.

Morning Sentinel Staff Writer Matt Hongoltz-Hetling can be contacted at 861-9287

mhhetling@centralmaine.com