Laboratory assessment of the molluscicidal activity of B-2, a new chemical against Oncomelania nosophora.

Laboratory trials of sodium 2.5 dichloro-4-bromophenol named B-2 for the molluscicidal effect against Oncomelania nasophora were carried out by Komiya's immersion technique. The values of LC50 of B-2 varied from 0.38 ppm to 0.54 ppm depending on the collection time of the snail. They were almost equal to those of NaPCP, but lower than those of Niclosamide. In the tests of toxicity to carp, rainbow trout and killifish, B-2 showed lower toxicity than NaPCP. Some aspects of mollusciciding application of the chemical were discussed.