DES MOINES - Rapidly warming weather and water temperatures have prompted concerns about microcystin, a product of blue-green algae.
Sun Valley Lake, a private lake and development in Taylor County, reported a small fish kill on Saturday in an area of the lake that appeared to have a blue-green algae bloom. The algae can deplete oxygen making fish vulnerable, particularly this time of year when fish are also stressed because of spawning activities.
Sun Valley Lake will be sampled by Iowa Department of Natural Resources for microsystin. Because the conditions are conducive to blue-green algae growth, people and pets should not be in contact with water that has a poor appearance. The appearance can be a pea-green or blue-green color, but also a reddish-brown. It may appear with scum, foam or as a thick mat on the water surface. Blue-green algae can grow quickly and become very abundant in warm, shallow, undisturbed surface water that receives a lot of sunlight.
The main risk to humans from microcystin is skin irritations and rashes, but if the water is swallowed or airborne droplets are inhaled during swimming, bathing or showering, symptoms could be worse. Those would include headaches, nausea, abdominal pain, seizures, liver injury and respiratory problems.
Precautions that should be taken to prevent health-related problems due to harmful algal blooms include: