Use of rainbow trout primary epidermal cell cultures as an alternative to immortalized cell lines in toxicity assessment: A study with nonoxynol

Increased concern has centered around environmental contaminants that exert estrogenic effects. A class of nonionic surfactants, the nonylphenol ethoxylates (such as the compound nonoxynol), are an example of one such group of contaminants. We studied the effects of nonoxynol (α‐(4‐nonylphenyl)‐ω‐hydroxypoly‐(oxy‐1‐ethanediyl)) on an epithelial primary culture. The culture system that was employed is a development of an in vitro technique for the culture of rainbow trout ( Onchorynchus mykiss ) epithelium, one that allows for the culture of both epithelial cells and goblet cells. The LC50 after 24 h was found to be 16.6 μmol/L. The LC50 after 48 h was 12.9 μmol/L. Nonoxynol was found to exhibit an acute lethal dose of 75 μmol/L. A decrease in the number of goblet cells present in the system was observed as exposure to nonoxynol increased. Nonoxynol was found to kill epithelial cells mainly by necrosis. A comparative study of the effects of nonoxynol on the epithelium papulosum cyprini cell line was also carried out. The LC50 of nonoxynol on this cell type was 4.1 μmol/L, with an acute lethal dose of 10 μmol/L.