The state Department of Environment Services issued an advisory Wednesday reporting a bloom of cyanobacteria along Elm Brook Park beach in Hopkinton.
Officials are warning beachgoers, and their pets, to be cautious of lake water that has “surface scum, changes in color, or appears to have green streaks or blue-green flecks aggregating along the shore.”
The advisory will remain in effect until the conditions return to state standards and the concentration of cyanobacteria cells have subsided.
Water samples collected from the beach Tuesday contained 537,7500, cells/ml of cyanobacteria taxa, well above the 70,000 cells/ml threshold established by DES. More samples taken Wednesday morning indicated the bloom has become more widespread, according to a press release from the agency.
“This advisory is not based on a toxin evaluation and is intended as a precautionary measure for short-term exposure,” DES officials said in the release. “Toxins can cause both acute and chronic health effects that range in severity. Acute health effects include irritation of skin and mucous membranes, tingling, numbness, nausea, vomiting, seizures and diarrhea. Chronic effects may include liver and central nervous system damage.”