Absence of genotoxicity of the carcinogenic sulfated polysaccharides carrageenan and dextran sulfate in mammalian DNA repair and bacterial mutagenicity assays.

The sulfated polysaccharides degraded carrageenan and dextran sulfate sodium were studied for genotoxicity using DNA repair tests employing cultured rat hepatocytes or intestinal mucosal cells. No evidence of unscheduled DNA synthesis was obtained. In addition, both alone and in combination with the comutagen norharman, these substances were nonmutagenic in the Salmonella microsome/mutagenicity test. These findings suggest that the carcinogenicity of the sulfated polysaccharides may be due to nongenotoxic mechanisms.