A new analysis from the Environmental Working Group reveals that state and federal testing of lakes and other bodies of water has found toxins from algae blooms in waterways in 48 states. Exposure to the toxins, which have occasionally made their way into drinking water supplies, can cause negative health outcomes ranging from skin rashes to serious illness or death.
“The bottom line is, if you test for microcystins, you’ll probably find them,” said Soren Rundquist, EWG’s director of spatial analysis, in a press release, referring to the toxins released by some algae. “Hundreds of lakes and other resources Americans rely on for tap water and recreation are contaminated — sometimes even when there is no visible toxic algae bloom.”
Algae blooms have often been linked to the runoff of fertilizers and other chemicals from agricultural operations. Water systems in several cities, including Toledo, Ohio; Salem, Oregon; and Greenfield, Iowa, have struggled to keep drinking water clear of algae-related toxins.
EWG analyzed data from 14 states that regularly test for algae-related toxins in water. Almost 9 percent of the samples done by all the states exceeded the EPA’s advisory guideline for exposure to the toxins. In eight states, drinking water samples exceeded a World Health Organization advisory level (which is lower than the EPA’s) more than 20 percent of the time.
A map accompanying the report illustrates where monitoring has identified contamination by the toxins. The full report can be accessed here.