Water samples are used to collect data for four chemical and two human health indicators.
Microcystins are a group of naturally occurring toxins produced by cyanobacteria (sometimes called blue-green algae) common in surface waters. Cyanobacteria in nutrient-rich, slow-moving water can form blooms. Not all blooms are toxic, but at elevated levels microcystins can harm humans, pets and wildlife. NRSA analyzes the risks from recreational exposure.
To learn more, see the
NRSA Field Operations Manual.