The molluscicidal effect of sodium pentachlorophanate and calcium arsenite on Oncomelania hupensis, a snail host of Schistosoma japonicum in China.

Sodium pentachlorophanate (P.C.P. Na) is now considered as one of the most promising molluscicides. Field experiments with this compound against Oncomelania nosophora in Japan were reported by McMullen and others (1948; 1951), and Hunter and others (1952). Since 1955 this compound has been used for practical molluscicidal purpose in the major endemic areas of schistosomiasis in Japan. In China, however, no application of this compound is yet found against Oncomelania hupensis, the vector snail of schistosomiasis in that country. They chiefly use B.H.C. and calcium arsenite for molluscicidal purpose. The latter compound was initially introduced as a molluscicide by the Chinese investigator (Su, 1954) and practically proved to be markedly effective. This compound acts as a food poison, and is now in practical use in the vast endemic areas in China. The aim of this experiment is to examine the molluscicidal effect on O. hupensis of both compounds, P.C.P. Na and calcium arsenite, in the laboratory.