Ecotoxicological assessment of the surfactants Linear Alkylbenzene Sulfonate (LAS) and Sodium Dodecyl Sulfate (SDS) based on a battery of aquatic bioassays.

The presence of surfactants in natural waters has become a growing environmental concern, as these substances, widely used in detergents, cleaning products, cosmetics, and industrial processes, can cause serious impacts on aquatic ecosystems, including deleterious effects on biota, depletion of dissolved oxygen, and eutrophication. This study presents a battery of ecotoxicological assays with different aquatic organisms to evaluate the acute, chronic, and sublethal toxic effects of anionic surfactants Linear Alkylbenzene Sulfonate (LAS) and Sodium Dodecyl Sulfate (SDS). The assays were performed with Vibrio fischeri bacteria, Daphnia similis crustaceans, Hyalella azteca amphipods, and Biomphalaria glabrata snails. Regarding LAS acute exposure, H. azteca was the most sensitive organism, followed by D. similis, B. glabrata, and V. fischeri, with E(L)C50 between 5.04 and 28.47 mg/L. Among the organisms exposed to SDS, the most sensitive were V. fischeri bacteria, followed by D. similis, H. azteca, and B. glabrata, with E(L)C50 values between 0.62 and 36.87 mg/L. Chronic effects on the reproduction of D. similis exposed to both surfactants were also observed, as well as teratogenic and lethal effects on B. glabrata embryos. The data obtained herein demonstrated the importance of evaluating the toxicity of surfactants to aquatic ecosystems, as these stressors caused different adverse effects in the exposed species.