Acute toxicity of BHC to four aquatic organisms namely, fish (Etroplus
maculatus) (Bloch), prawn (Macrobrachium idella idella) (Hilgendorf),
clam (Villorita cyprinoides var Cochinesis (Hanley) and crab (Paratel
phusa hydrodromus) (Herbst) were determined by conducting short term,
static bio-assays. The organisms were exposed to different concentrati
ons of BHC (HCH-technical solution) and LC(50) values were determined
for each organism. Ninety Six hour LC(50) values for fish, prawn, clam
and crab were 0.7, 0.0125, 13 and 5.8 ppm respectively.