Acute toxicity of Phytolacca dodecandra (Endod‐S) and Niclosamide to snails, Schistosoma mansoni cercaria, Tilapia fish, and soil microorganisms

Abstract

AbstractThe acute toxicity of two molluscicides, the extract of the plant Phytolacca dodecandra (Endod‐S) and Niclosamide, was determined using the following test species: The snails Biomphalaria glabrata (albino) and Biomphalaria pfeifferi, Schistosoma mansoni cercaria, and Tilapia nilotica fish. Endod‐S showed a 24‐h LC50 of 2.57 and 5.37 mg/L for B. glabrata (albino) and B. pfeifferi respectively. Niclosamide produced a 24‐h LC50 of 0.063 mg/L and 0.049 mg/L for B. glabrata (albino) and B. pfeifferi, respectively. The 4‐h LC50 for S. mansoni cercaria was 2.92 mg/L for Endod‐S and 0.0008 mg/L for Niclosamide. The 24‐h LC50 for Tilapia nilotica was 1.82 mg/L for Endod‐S and 0.21 mg/L for Niclosamide. The toxicity of Endod‐S and Niclosamide to a mixed population of soil microorganisms was measured using oxygen uptake and growth as measured by turbidity. Endod‐S was not toxic to the microorganisms. The average Niclosamide toxic end point (IC50) for these bacteria was 450 mg/L.