From Phyco.org
Though many algae are poisonous, cyanobacteria present the greatest risk to people who handle algae. This paper explains how to rate risks using algal appearance, season, wind and weather.
Toxic algae contain a variety of poisonous substances, which may cause a variety of symptoms. Handling algae may cause skin irritation. Getting a toxic algae culture in your eye can be serious. Ingesting toxic algae can kill.
See: Algae and Cyanobacteria in Fresh Water
