Notes on the pathogenicity of Bacillus thuringiensis var. thuringiensis Berliner for the earthworm, Lumbricus terrestris Linnaeus
Authors: Smirnoff, W.A., Heimpel, A.M.
Journal, Volume, Year: Journal of Insect Pathology, volume 3:403-408, 1961
Earthworms (Lumbricus terrestris) were placed in jars containing 300 g of humus-rich, granular clay soil containing maple, birch, or elm leaves. Two types of bacterial preparations (Thuricide 30B or Thuricide 50B) were then added to the soil at concentrations of 3, 15, 30, and 60 g. Total mortality was observed in <2 months with the smallest dose. Massive septicemia developed in the earthworms before death occurred.
One of earliest studies conducted that evaluated effects of Bt on non-target species. The doses used in this study were extremely high, 10,000 to 100,000 times higher than would occur after normal applications in the field.