Toxic blue-green algae blooms have prompted Massachusetts officials to warn residents not to swim in various bodies of water including the Charles River, various ponds on Cape Cod, and Pontoosuc Lake.
The Massachusetts Department of Public Health has issued a cyanobacteria (blue-green algae) advisory for the lower Charles River Basin, according to WBUR.
News outlets warned residents that contact with harmful algae blooms can cause mild gastrointestinal upset and irritate the skin. In the worst-case scenario it can cause serious complications to the liver and kidneys, and in some rare events it has caused death, according to the DPH.
Massachusetts doesn’t typically see the blooms, but the extremely high temperatures and massive amounts of rain have caused them to proliferate all the way up the East Coast.
Biologists say that warmer water temperatures and increasing phosphorus help trigger more frequent and severe algae blooms in Florida lakes; Melbourne citizens recently showed up to a town hall meeting to complain about the smelly water coming from their taps, concerned that the blooms in Lake Washington were not being filtered out, according to Florida Today.
Last month the National Oceanic and Atmospheric Administration predicted that the Gulf of Mexico dead zone — caused by vast algae blooms — would be the size of Massachusetts. This month, NOAA predicted that Lake Erie, which provides drinking water to 11 million people, will also experience a massive harmful algae bloom, starting in late July, according to Ohio State News.
This year’s bloom is expected to measure 7.5 on the severity index, but could range between 6 and 9. An index above 5 indicates blooms having greater impact.
The largest blooms occurred in 2011, with a severity index of 10, and 2015, at 10.5.