Resumen de Comparative study of the acute toxicity of anionic surfactans alkyl benzene sulphonate (ABS) and sodium dodecyl sulphate (SDS) on gilthead, Sparus aurata L., eggs

Miguel Angel Rosety, Francisco Javier Ordóñez Muñoz, Manuel Rosety-Rodríguez, Jesús María Rosety Rodríguez, Ignacio Rosety, María del Carmen Carrasco Molinillo, Antonio Ribelles García

• In the present work we have evaluated the acute toxicity of t wo anionic surfactants, alkyl benzene sulphonate (ABS) and sodium dodecyl s ulphate (SDS) to eggs of g ilthea d Sparlls aura /a . At each s ur factant conce ntratio n, we determined the exposure time required fo r 50% mortalit y of the eggs (LT50), surface te nsio n and volume of oil globule in gilt hea d eggs. Clea r dose-r espo nse relatio nships for mortality of g ilthea d eggs was observed for both toxicants; at 30 mgl L 50% mortality took place at 45 minutes for A BS and 8 minutes for SDS. At this conce ntration, SDS was a lmost s i x times mo re to xi c th a n A BS ( LT50 is compared ). However, at 0 .3 mg/ L 50% mo rt a lity occurred after exposures of 535 minutes to ABS and 425 minutes to SDS. Descriptively, our results showed SDS was more toxic than ABS at high conce ntrations whereas at l ow concentratio ns the ir toxicity was very similar. However, statistica l analys is demonstrated there were no significant differences in the toxicity of both surfactants to gilthead eggs. Surface tension value at each concentration of both sur factants was a lso calculated. We found that these values dec reased with increasing conce ntratio n o f each s urfactant , and this tr e nd was mo re pro no unced in so lutio ns of S DS. We also found that the volume of the oil g lobule of e xposed eggs was in f lu e nced b y s urfactants. After exposure, its volume clearly dec reased in compar ison to controls, ma inly in eggs exposed to SDS.