Teratogenic and toxic effects of alcohol ethoxylate and alcohol ethoxy sulfate surfactants on Xenopus laevis embryos and tadpoles

The two surfactants tested, an alcohol ethoxylate (AE) and an alcohol ethox y sulfate (AES), demonstrate both teratogenic and toxic effects in Xenopus laevis embryos and tadpoles. From acute tests and observations of malformat ions under light and electron microscopy, the AES produced less teratogenic and toxic effects than the AE, from which it differs only by the presence of a sulfate in the hydrophilic group of the molecule. The 72-h LC50 was 4. 59 mg/L for the AE and 6.75 g/L for the AES. The tissues most affected were the epithelia, particularly of the gills. As the AE exhibited ultrastructu ral alterations of mitochondria and narcotic effects, O-2 consumption was s tudied in treated tadpoles; results indicated collapse of the electrochemic al gradient in mitochondria. (C) 2001 Academic Press.