A single-use field screen for microcystins and nodularins, the liver toxins most often produced by blue-green algae (cyanobacteria). Collect a sample at the shoreline, run the test, and read the cassette on site in about twenty minutes.

A bloom tells you algae are present. It does not tell you whether toxin is. This test answers that question where the water is used, so a lake community can decide whether to post a caution at a beach or boat launch today rather than after a lab report comes back.

It is a screen, not a certified result. A positive should be confirmed by laboratory analysis before it drives a formal advisory.