Determination of the lethal doses LD50 and LD90 of Euphorbia splendens var. hislopii latex on Physa cubensis Pfeiffer

The genus Physa are among the most common and widespread fresh-water snails and are frequently associated with the genus Lymnaea and Biomphalaria, typically occupying the same habitat and being hosts of trematodes that can cause disease in humans. Several studies have evaluated the control of snails through the use of plant-derived molluscicides; however, few such studies exist regarding the genus Physa. Determining the correct lethal doses of [latex of Euphorbia splendens] is important for the control of the Physa cubensis snail. In one experimental model, 150 snails from Jacarepagua, Rio de Janeiro, RJ were used. After acclimatization for 72 hours, the snails were divided into groups of 10 and placed into beakers containing different doses, each at a temperature of 26±1oC and a relative humidity of 80±10%. The results demonstrated LD50 of 1.08 µL/L and LD90 of 3.41 µL/L, without significant changes in the physical or chemical parameters of the solutions. We conclude that E. splendens latex had a significant effect on P. cubensis in the laboratory setting.