Summary:

- Lake Victoria, the world's second-largest freshwater lake, is turning green due to the proliferation of cyanobacteria, a type of harmful algae.
- The cyanobacteria, which produce toxins, are thriving in the lake due to increased nutrient pollution from agricultural runoff, sewage, and industrial waste.
- The green algal bloom is posing a serious threat to the lake's ecosystem, as well as the health and livelihoods of the millions of people who depend on the lake for their water supply, fishing, and other activities.