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Toxicity of volcanic-ash leachate to a blue-green alga. Results of a preliminary bioassay experiment

January 1, 1981

To assess the possible effects of volcanic ash from the May 18,1980, eruption of Mt. St. Helens, Washington, on aquatic ecosystems, we conducted a bioassay experiment with a blue-green alga, Anabaena flos-aquae. Results showed that leachate (obtained by leaching 151 g of ash with 130 mL of simulated freshwater) was lethal to Anabaena flos-aquae cultures when diluted as much as 1:100 with culture medium. Cultures exposed to a 1:500 dilution grew, but a toxic effect was indicated by abnormalities in the Anabaena filaments. This study indicates that ash from the Mt. St. Helens volcano could have an effect on aquatic ecosystems in the areas of significant ashfall. Further study is needed to determine the toxic chemical constituents in the ash and also its possible effects on other aquatic organisms.

Citation Information

Publication Year 1981
Title Toxicity of volcanic-ash leachate to a blue-green alga. Results of a preliminary bioassay experiment
DOI
Authors Diane M. McKnight, G.L. Feder, E.A. Stiles
Publication Type Article
Publication Subtype Journal Article
Series Title Environmental Science & Technology
Series Number
Index ID 70011729
Record Source USGS Publications Warehouse
USGS Organization