Evaluación a nivel de laboratorio de la sensibilidad de spirogyra spp. chlorella sp. Como bioindicadores de surfactantes aniónicos (detergentes)

Abstract

The objective of this research was to evaluate the sensitivity of algae, Chlorella sp and Spirogyra spp, as bioindicators of the presence of surfactants: Sodium Lauryl Sulfate (SLS), Dodecylbenzene Sulfonic Acid (ADS) and Sodium Lauryl Ether Sulfate (SLES). Initially, the experimental units were prepared for the adaptation and growth of the crops of the mentioned species; PVC containers of 5 L capacity were used, nutrition and environmental conditions such as light supply and temperature were guaranteed, and the air was supplied. To provide an adequate amount of O2, once the organisms had adapted, three doses of surfactants were added to the experimental units at concentrations of 10ppm, 20ppm and 30ppm for an exposure time of 120 hours. Different levels of sensitivity of the species to contact with surfactants were evidenced, highlighting physiological and morphological changes such as discolouration, detachment of filaments, destruction of chloroplasts and reduction of algal biomass during the exposure stage, especially in the experimental units 3, which had higher concentrations and dosages where they showed the highest degree of affectation, concluding that ADS is the most aggressive anionic surfactant with the tested species. Finally, the bioaccumulation of surfactants was analyzed, demonstrating that in both species, the ADS with values in Spirogyra spp. of 0.430 ± 0.2471 mg/L and Chlorella sp. of 0.108 ± 0.2471 mg/L is the one that most bioaccumulated. Furthermore, it is concluded that Spirogyra spp. and Chlorella sp. are efficient bioindicators of the anionic surfactants tested due to the evident changes in responses to stimuli caused by the exposure. It is recommended to evaluate the qualities of the two species in future research with exposures to other frequent polluting substances and in the treatment of water contaminated with detergents.