Comparative toxicity of sulfur mustard and nitrogen mustard on tracheal epithelial cells in primary culture.

Abstract Sulfur mustard (SM) and mechlorethamine (HN2) are two alkylating agents. SM represents a potential chemical warfare agent and HN2 is used in cancer chemotherapy. Based on the similarities of their action, although few comparative studies of their effects have been performed on the same model, many compounds effective against HN2 side-effects have been proposed, unsuccessfully, against SM-induced lesions. We performed this study to compare the toxic effects of these two alkylating agents on rabbit tracheal epithelium in primary culture. Using neutral red uptake, we evidenced that for a time of contact of 24 hr, HN2 LC 50 was significantly lower than SM LC 50 (0.034±0.009 and 0.132±0.023 m m , respectively; P −3 m , the time necessary to decrease the cell viability rate to 50% was shorter with SM than with HN2 (11±1 min and 54±2 min, respectively; P