LUSBY, Md. – Water test results from Lake Lariat revealed historically high levels of microcystin toxin in all three areas tested. The recent toxin measurements are close to 3 times higher than any previously recorded level and are >30 times higher than what is considered safe for human contact. This toxin is produced by certain blue-green algae that have accumulated in the lake this year likely due to an increased concentration of nutrients which may be a result of lower water levels and relatively little rainfall. High temperatures have further accelerated the growth of algae.
We are very concerned for the well-being of the citizens who use this lake for recreational purposes as well as for their pets. This toxin poses a health risk to humans and pets both through contact and ingestion pathways. While we have posted advisories on the beach and boat ramp for many years when algae levels have risen, the toxin levels that we are seeing this year greatly exceed anything in the past. Therefore, we are recommending closure of the beach for swimming, bathing and other recreational activities where people will be in contact with the water.
The toxins associated with blue-green algae are particularly dangerous to children and pets. The major risk to humans is liver damage due to inadvertent ingestion of water. People are also at risk for allergic reactions and breathing problems as a result of toxin exposure. Dogs, in particular, are drawn to drinking algae-infested water. Over the past several decades, numerous canine deaths have been reported across the U.S. as the direct result of drinking water with high algae toxin levels. Because of these risks, it is also advisable to inform property owners who own land adjacent to the lake of the toxin concerns. We believe that it is still safe for people to sunbathe, perform other recreational activities on the sand as well as boating provided that direct water contact is not part of any of those activities.
We are anticipating a substantial amount of rainfall in the near future and hope that this will help to improve conditions with the algae bloom that we are seeing. The Health Department plans to schedule additional sampling in the near future and will make those results available as soon as possible.