A study published this week by the Public Health Institute and the institute’s Tracking California program shows that microcystin, a toxin produced by cyanobacteria, contaminated private drinking water that many community members rely on in Lake County. The Lake CountyNews reports that over 60% of residents in Lake County receive their drinking water from Clear Lake, the largest freshwater lake in the state. It’s estimated that 500 homes around the lake have private drinking water supplies — either lake water intakes or near-shore wells. Nearly 70% of the homes with lake water intakes tested showed levels of the toxin above the standard. Homes with near-shore wells did not show contamination. The study also suggested that long-term solutions to the issue in the future are necessary, such as transitioning households to public water systems, and Harmful Algae Bloom mitigation.