Harmful algae blooms have become a top water polluter, fueled by fertilizers washing into lakes, streams and oceans. Federal and state programs have spent billions of dollars on cost-sharing payments to farmers to help prevent nutrient runoff, yet the problem is worsening in many places.
Here’s a look at the algae menace and what’s being done: Among the oldest life forms, algae are simple aquatic plants that form key links in food chains. Some types of bacteria are also considered algae, including cyanobacteria, or "blue-green algae," which is increasingly common across the U.S.
Scientists believe a combination of factors can trigger large blooms, including warm temperatures, slow water circulation and excessive nutrients, especially nitrogen and phosphorus. Among nutrient sources are runoff from farms and urban lawns as well as industrial wastes and sewage. Some blooms generate toxins such as microcystin, which can cause nausea, fever and liver damage in humans and kill animals. A federal study detected microcystin […]