Skip Links

USGS - science for a changing world

Scientific Investigations Report 2007-5048

Prepared in cooperation with the Orange County Water District, Fountain Valley, California

Discovery of Cyanuric Acid During an Assessment of Natural Organic Matter in Stormflow Water of the Santa Ana River, Southern California, 2003–2004

By Jerry A. Leenheer, John A. Izbicki, Colleen E. Rostad, Ted I. Noyes, and Greg Woodside

Thumbnail of and link to report PDF (1.1 MB)Download Publication
Scientific Investigations Report
2007-5048 PDF (1.1 MB)

A stormflow study of natural organic matter and organic contaminants in the Santa Ana River, the Mill Creek tributary, and an urban drain tributary discovered cyanuric acid in variable concentrations up to 510 μg/L. Cyanuric acid was isolated with a hydrophilic natural organic matter (NOM) fraction, and its identity was confirmed by a combination of infrared spectrometry, 13C-nuclear magnetic resonance (13C-NMR) spectrometry, and electrospray ionization/mass spectrometry. Cyanuric acid concentrations, based upon 13C-NMR spectral quantitation, increased during the peak and recessional flows of the storm hydrographs during three storms at three sites. The greatest fluxes of cyanuric acid were observed in the Santa Ana River during the third storm. The most likely source of cyanuric acid is as a metabolite of triazine herbicides, based on hydrographs, land uses of the drainage basins, and the yearly application rates of triazine herbicides. The daily flux of cyanuric acid in Santa Ana River stormflow during the third storm was calculated to be about 1 percent of the yearly application rate for triazine herbicides. Cyanuric acid was not detected in ground water at wells adjacent to the Santa Ana River.

Version 1.0

Posted January 2008

Suggested citation:

Leenheer, J.A., Izbicki, J.A., Rostad, C.E., Noyes, T.I., and Woodside, Greg, 2008, Discovery of cyanuric acid during an assessment of natural organic matter in stormflow water of the Santa Ana River, southern California, 2003–2004: U.S. Geological Survey Scientific Investigations Report 2007–5048, 13 p.




Hydrologic Setting

Methods and Approach

Sampling Approach

Preparative Dissolved Organic Matter Fractionation and Isolation Procedure

Fourier Transform-Infrared Spectrometry

Solid-State Cross-Polarization Magic Angle Spinning 13C-Nuclear Magnetic Resonance Spectrometry

Electrospray Ionization/Mass Spectrometry

Chemical Standard

Cyanuric Acid in Stormflow Water

Storm Hydrographs

Dissolved Organic Matter Fractionations

Spectral Characterizations of Cyanuric Acid in Hydrophilic Acid plus Neutral Fractions

Possible Sources of Cyanuric Acid



Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Acrobat Reader or similar software is required to view it. Download the latest version of Acrobat Reader, free of charge or go to for free tools that allow visually impaired users to read PDF files.

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo logo U.S. Department of the Interior | U.S. Geological Survey
Page Contact Information: Contact USGS
Page Last Modified: Thursday, December 01 2016, 07:56:52 PM