Environmental Health - Toxic Substances Hydrology Program

EH Science Feature Email Signup

Toxins Produced by Molds Measured in U.S. Streams

Early spring view of a stream in Iowa with melting snow
Highest stream mycotoxin concentrations were observed during spring snowmelt conditions in agricultural settings such as pictured in this Iowa stream. Photo Credit: Kate Holt, USGS.

A team of scientists from the U.S. Geological Survey (USGS) and the Agroscope Reckenholz-Tanikon Research Station, Switzerland, found that some mycotoxins are common in U. S. stream waters. Mycotoxins are toxic compounds produced by molds (fungi) that can cause disease and even death in humans and animals. Mycotoxins can grow on a wide variety of crops.

The scientists collected 116 water samples from 32 streams and the discharge from three wastewater treatment plants. They analyzed the samples for 33 mycotoxins, and 9 were detected. At least one mycotoxin was detected in 109 of the 116 samples. The concentrations detected were primarily in the range of a part per trillion (nanograms per liter [ng/L]) to a part per billion (micrograms per liter [µg/L]) and were generally less than 50 ng/L. However, concentrations exceeding 1 mg/L were measured in agricultural settings during spring snowmelt and in wastewater treatment plant effluent.

Deoxynivalenol, the most frequently detected mycotoxin, was detected in 77 percent of the samples, followed by nivalenol (59 percent), and beauvericin (43 percent). Three of the mycotoxins are known estrogenic compounds (zearalenone, α-zearalenol, and β-zearalenol). One or more of these three compounds were detected in 43 percent of the samples, and their maximum concentrations were substantially higher than observed in previous research.

This study is the broadest evaluation conducted to date of the spatial and temporal occurrence of mycotoxins in U.S. streams. The results suggest that both diffuse and point sources are important environmental pathways for mycotoxin transport to streams. The study was supported by the USGS Toxic Substances Hydrology Program and the Swiss Federal Office for the Environment.


Kolpin, D.W., Schenzel, J., Meyer, M.T., Phillips, P.J., Hubbard, L.E., Scott, T.-M., and Bucheli, T.D., 2014, Mycotoxins—Diffuse and point source contributions of natural contaminants of emerging concern to streams: Science of the Total Environment, v. 470-471, p. 669-676, doi:10.1016/j.scitotenv.2013.09.062.

More Information

This article was featured as an article in the USGS GeoHealth Newsletter, Vol. 11, No. 1, 2014

Related Science Features


More Science Features


USGS Home Water Land Resources Science Systems Ecosystems Energy and Minerals Environmental Health Hazards

Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
Page URL: toxics.usgs.gov/highlights/2014-06-13-mycotoxins.html
Page Content Contact Information: webmaster@toxics.usgs.gov
Page Last Modified: 27-Jun-2018 @ 07:15:42 PM EDT