SENSITIVITY EVALUATION OF Biomphalaria glabrata (SAY, 1818) ADULTS AND EMBRYOS EXPOSED TO SODIUM DODECYL SULFATE
Silva FNV, Nakano E, Tallarico LF
Laboratório de Parasitologia, Instituto Butantan, Brasil
Introduction: The sodium dodecyl sulfate (SDS) is an anionic surfactant widely used in professional and household cleaning supplies. This substance is often present in personal care products and can be found in the pharmaceutical industry. Currently, it is known that there is a wide release of this compound into the aquatic environment, which can cause biochemical and physiological changes to several trophic levels. Therefore, there is a relevance in determine the toxic effects of this substance to organisms that have importance in environmental and public health, as the freshwater snail Biomphalaria glabrata. Objectives: In this work, preliminary acute toxicity test with gastropods were performed to evaluate the sensitivity of the exposition to sodium dodecyl sulfate. Methods: Adult snails and embryos in blastula stage were selected from populations cultured in the laboratory. These organisms were exposed to the surfactant during 24 hours at concentrations of 100, 50, 25 and 12.5 mg/L, as well as a control group was exposed in the same conditions. After this period, the animals were placed in the filtered water until the end of assay, which lasted seven days. Thirty adult snails and a minimum of fifty embryos were selected for each concentration. The variables observed were mortality and malformation. Results and Discussion: For adults, LC50 (Median Lethal Concentration) was 35.52 mg/L and for blastula stage the EC50 (Effective Concentration Mean) was 69,06 mg/L. It was observed teratogenic effect on the embryos at all exposure concentrations, and to adult a large quantity of hemolymph was released at higher concentrations. Moreover, during the first day of the test, it was observed an extension of the animal body out of the shell, with the male reproductive organ exhibited. This event possibly occurred due to irritant action of the substance in the tegument of these animals. From the establishment of concentrations to the acute toxicity tests and sensitivity verification of the snail to the compound, as shown in this work, it will be elaborate the control chart for the SDS surfactant. In addition, chronic toxicity studies with adults and embryos will be performed at all snail developmental stages.
|11 - SYSTEMS BIOLOGY||21th Annual Scientific Meeting of Instituto Butantan.|