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Rapid method for determining concentrations of Bayer 73 in water during lampricide treatments

January 1, 1978

Two simple, rapid, sensitive methods were developed for determining the concentration of the lampricide 2',5-dichloro-4'-nitrosalicylanilide (Bayer 73) in stream water. Bayer 73 was extracted from acidified water samples with chloroform and then hydrolyzed to 2-chloro-4-nitroaniline (CNA) with either acid or base. The CNA was diazotized with sodium nitrite, and an azo dye was formed with either N-( 1-naphthyl) ethylenediamine dihydrochloride (after acid hydrolysis) or 1-naphthol (after base hydrolysis). There was no interference from the lampricide 3-trifluoromethyl-4-nitrophenol (TFM) in either method. Standard curves were prepared with untreated water to compensate for interfering substances that occurred naturally in some streams. The methods were sensitive to about 0.005 mg/L (ppm). Time required for analysis of a sample ranged from 25 min to 1 h.

Publication Year 1978
Title Rapid method for determining concentrations of Bayer 73 in water during lampricide treatments
DOI 10.1139/f78-196
Authors V. K. Dawson, P.D. Harman, D.P. Schultz, J. L. Allen
Publication Type Article
Publication Subtype Journal Article
Series Title Journal of the Fisheries Research Board of Canada
Index ID 70006789
Record Source USGS Publications Warehouse
USGS Organization Upper Midwest Environmental Sciences Center