HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Call, D. J. Articles by Slick, E. J. Search for Related Content PubMed Articles by Call, D. J. Articles by Slick, E. J. Agricola Articles by Call, D. J. Articles by Slick, E. J.

Toxicity, Uptake, and Elimination of the Herbicides Alachlor and Dinoseb in Freshwater Fish¹

ABSTRACT

Fathead minnows (Pimephales promelas) 30 d of age were exposed to technical grade alachlor [2-chloro-2' ,6'-diethyl-N-(methoxymethyl)acetanilide] and dinoseb (2-sec-butyl-4,6-dinitrophenol) in flow-through tests to determine acute toxicity. Median lethal concentrations (LC₅₀ values) for alachlor were 9.9, 6.6, 5.0, and 3.0 mg L^–1 at 24, 48, 96, and 192 h, respectively; and for dinoseb were 0.8, 0.7, 0.7, and 0.5 mg L^–1, respectively. Early life-stages of the fathead minnow (embryos, fry, and juveniles) were exposed to lower concentrations of each compound for a total of 64 d. The "no effect" concentration was estimated to lie between 0.52 and 1.10 mg L^–1 for alachlor and between 14.5 and 48.5 µg L^–1 for dinoseb. Neither herbicide was appreciably accumulated in fish tissue. Whole body bioconcentration factors for parent ¹⁴C-alachlor and ¹⁴C-dinoseb were 6.0 and 1.4, respectively. Rainbow trout (Salmo gairdneri) injected with radiolabeled herbicides eliminated 83% of the radioactivity within 24 h as a combination of parent compound and metabolites.

These laboratory studies suggest that the accumulation of alachlor and dinoseb residues and the toxicity of alachlor do not present great environmental risks to fish. However, the toxicity of dinoseb may pose some risk.

Key Words: acute • early life stage • bioconcentration • metabolism • pesticide

¹ Contribution from Center for Lake Superior Environ. Studies, Univ. of Wisconsin-Superior, Superior, WI 54880.

² Biologist, Biologist, Biochemist (presently chemist with EPA Office of Toxic Substances, Washington, DC), Biologist, Chemist, Biologist (presently Graduate Student, Dep. of Fisheries & Wildlife Sci., Oregon State Univ.), and chemist (presently chemist with NIOSH in Cincinnati, OH), respectively.

Received for publication August 15, 1983.