OLYMPIA – Thurston County Public Health and Social Services is reporting a toxic algae bloom at Black Lake. The state advisory level for microcystins are 8.0 ug/L and the lab results show toxin levels of microcystins at the sample site at Black Lake are 33 ug/L.
Microcystins are a liver toxin and possible human carcinogen. Microcystins can also cause illness in livestock and pets that drink affected water. Staff will collect weekly samples until the algae bloom clears. Warning signs are posted at the boat launch and other locations around the lake.
When an algae bloom is present, health officials recommend taking extra precautions to avoid the health risks posed by potential toxins.
- Do not drink the lake water.
- Avoid contact with water containing algae.
- Avoid swimming, wading, wind surfing and water-skiing in waterbodies where algae blooms are present.
- Keep pets and livestock away from where algae blooms are present.
- Do not eat fish that come from the lake during an algae bloom.
- Avoid areas of scum when boating.