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Effects of the mosquito larvicide GB-1111 on red-winged blackbird embryos

P.H. Albers·D. J. Hoffman·D.M. Buscemi·M. J. Melancon
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Abstract

Golden Bear Oil (GB-111 I; legal trade name for GB-1313) is a petroleum distillate that is used in the United States and other countries as a larvicide for mosquito suppression. As part of a multi-species evaluation of the potential effects of GB-1111 on birds, red-winged blackbird eggs were collected, artificially incubated, and treated with one of five amounts of GB-1111 varying from 0 to 10 times the expected exposure from a spray application of the maximum recommended amount (X=47 l/ha, 5 gal/ac). The application of 10 X caused a significant reduction in hatching success. A dose-related reduction of hepatic microsomal mono-oxygenase activity (EROD) was detected. Among body weights, skeletal measurements, and age at death, only crownrump length was different among experimental groups. Overall, the potential hazard to embryos of a representative wetland passerine appears minimal until the application rate exceeds 3 X.

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P.H. Albers, D. J. Hoffman, D.M. Buscemi, M. J. Melancon. 2003. Effects of the mosquito larvicide GB-1111 on red-winged blackbird embryos. https://pubs.usgs.gov/publication/5224259

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