Aqueous extracts of latex and stem bark of Codiaeum variegatum and Croton tiglium (Euphorbiaceae) have a high molluscicidal activity. It was observed that the molluscicidal activity of extracts of both the plants against two harmful freshwater snails Lymnaea acuminata and Indoplanorbis exustus was time as well as dose dependent. There was a significant negative correlation between LC50 values and exposure periods thus increase in exposure time, the LC50 of Croton tiglium and Codiaeum variegatum

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... latices were decreased from 0.060 mg DW/L (24h)> to 0.014 mg DW/L (96h) and 0.381 mg DW/L (24h)> to 0.159 mg DW/L (96h), respectively against Lymnaea acuminata and 0.034 mg DW/L (24h)> to 0.009 mg DW/L (96h) and 0.246 mg DW/L (24h)> to 0.030 mg DW/L (96h), respectively against Indoplanorbis exustus. These plant part extracts at higher doses were also lethal to freshwater fish Channa punctatus, which shares the habitat with these snails, but the doses LC90, (24h) of snails are safe for fish.