Toxic algae again plaguing Grand Lake St. Marys

CELINA, Ohio (AP) — Toxic algae blooms are again plaguing Ohio's largest inland lake.

Signs were going up Thursday at Grand Lake St. Marys to warn visitors that toxic blue-green algae has made the water unsafe for swimming. It's a familiar problem at the 20-square-mile lake between Dayton and Toledo.

The Columbus Dispatch ( ) reports state officials have been testing near lake beaches this week after measurements of a liver toxin associated with the algae began to increase last month near where the city of Celina draws water into its treatment plant.

Ohio Department of Natural Resources spokesman Matt Eiselstein says the readings are "definitely over the safety level."

Blue-green algae are common in most Ohio lakes, fed by phosphorus from manure, fertilizers and sewage that rain washes from farm fields into nearby streams.