Cyanotoxin, chlorophyll-a, and cyanobacterial toxin genetic data for samples collected at eleven large river sites throughout the United States, June through October 2018

This U.S. Geological Survey (USGS) data release provides discretely measured cyanotoxin, chlorophyll-a, and cyanobacterial toxin genetic data for samples collected from eleven large river sites throughout the United States, from June through October 2018. Discrete water-quality samples were analyzed for cyanotoxins (anatoxin, cylindrospermopsin, microcystin, and saxitoxin), chlorophyll-a, and cyanobacterial toxin genetics as part of a National Water-Quality Assessment Project pilot study to describe cyanobacteria and cyanotoxin occurrence in the Nation's large rivers.