DAO 51:37-47 (2002)  -  doi:10.3354/dao051037

ABSTRACT: The effects of exposure to sublethal concentrations (1.5 and 3\qmg\ql^-1) of sodium dodecylbenzene sulphonate on the olfactory epithelium of Ictalurus melas Rafinesque were examined by light and scanning electron microscopy. The detergent affected the superficial part of each olfactory lamella and different morphological alterations, depending on dose and duration of treatment, were observed. The histology and surface morphology of sensory and non-sensory areas of the epithelium of fish treated with 1.5\qmg\ql^-1 for 5 and 10\qd were not affected by the treatment, while only an incipient thinning-out of the long cilia of non-sensory epithelium was seen in fish treated for 15\qd. Treatment with 3\qmg\ql^-1 caused morphological alterations, related to the time of exposure, in the non sensory and sensory epithelium, consisting of progressive thinning of cellular projections; this treatment also increased mucus production. These observed histopathological changes in the olfactory mucosa may modify the olfactory perception of the fish, and could thereby impair important physiological functions such as feeding, social interactions or migration.

KEY WORDS: Anionic detergent · Morphological changes · Ictalurus melas · LAS · Olfactory mucosa · Scanning electron microscopy · Sodium dodecylbenzene sulphonate