A novel molluscicidal formulation of niclosamide

Snail control by molluscicides is an important strategy for schistosomiasis control in China. Currently, only one chemical molluscicide, niclosamide, which is used as 50% wettable powder of niclosamide ethanolamine salt (WPN), is commercially available for field snail control in China. However, WPN is costly, toxic, and has a lower dispersibility and precipitates rapidly. In this paper, we describe the development of a novel formulation of niclosamide, a suspension concentrate of niclosamide (SCN). The efficacy of SCN was evaluated both in the laboratory and field. SCN showed better molluscicidal effects than conventional formulation of WPN, as determined by LC(50) for adult snails, young snails, and snail eggs. The acute toxicity of SCN to Brachdanio rerio hamiton was less than WPN. In conclusion, the novel formulation of SCN suspension is physically more stable, more effective, and less toxic. Therefore, it can be more useful for controlling snails in endemic areas of schistosomiasis in China.