Lakes, reservoirs, rivers and streams are critical sources of drinking water. But they’re threatened by toxic algae blooms, fueled by polluted runoff from farms and made worse by climate change.

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EWG’s ongoing tracking has found more than 1,000 communities with news reports of algae blooms in 49 states since 2010 – an increase of more than 600 percent in the past decade.

Health effects of cyanotixin table
Tip Sheet

Algal blooms don’t always produce toxic microcystins. When they do they’re not just a gross and smelly nuisance, but can pose serious health hazards to people, pets and wildlife.

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