Gretchen Onstad, PhD

Research Interests

  • Drinking water quality and treatment, analytical method development, oxidation kinetics, disinfection byproducts, harmful algal blooms, source apportionment of chemical contaminants (nitrates, fracking fluid) in household wells and removal by point-of-use water treatment.
Selected Publications

Onstad G.D., Canfield D., Quay P., and Hedges J.I. (2000) Sources of particulate organic matter in rivers from the continental USA: Lignin phenol and stable carbon isotope compositions. Geochimica et Cosmochimica Acta. 64:20:3539-3546.

Onstad G.D. and Weinberg H.S. (2005) Evaluation of the stability and analysis of halogenated furanones in disinfected drinking waters. Analytica Chimica Acta. 534:2:281-292.

Ho L., Onstad G., von Gunten U., Rinck-Pfeiffer S., Craig K., Newcombe G. (2006) Differences in the chlorine reactivity of four microcystin analogues. Water Research. 40:6:1200-1209.

Krasner S.W., Weinberg H.S., Richardson S.D., Pastor S.J., Chinn R., Sclimenti M.J., Onstad G.D., Thruston, Jr., A.D. (2006) Occurrence of a new generation of disinfection byproducts. Environmental Science and Technology. 40:7175-7185.

Onstad G.D., Strauch S., Meriluoto J., Codd G., von Gunten U. (2007) Selective oxidation of key functional groups in cyanotoxins during drinking water ozonation. Environmental Science and Technology. 41:12:4397-4404.

Rodriguez E., Onstad G.D., Kull T.P.J., Metcalf J.S., Acero J.L., von Gunten U. (2007) Oxidative elimination of cyanotoxins: Comparison of ozone, chlorine, permanganate and chlorine dioxide. Water Research. 41:15:3381-3393. (shared first-authorship)

Onstad G.D., Weinberg H.S., Krasner S.W. (2008) Occurrence of Halogenated Furanones in U.S. Drinking Waters. Environmental Science and Technology. 42:9:3341-3348. Featured by Chemical & Engineering News ("Minimizing Halogenated Mutagens in Water: Water-treatment process affects formation of toxic compounds" March 31, 2008, 86:13:26)

Sullivan A.P., Frank N., Onstad G., Simpson C.D., Collett Jr. J.L. (2011) Application of High-Performance Anion-Exchange Chromatography – Pulsed Amperometric Detection for Measuring Carbohydrates in Routine Daily Filter Samples Collected by a National Network: 1. Determination of the Impact of Biomass Burning in the Upper Midwest. Journal of Geophysical Research-Atmospheres. 116:D08302.