l-ascorbic acid , citric acid or their sodium salts ( at levels equivalent to 5 % sodium l-ascorbate ) were fed in the diet simultaneously with n-butyl-n- ( 4-hydroxybutyl ) nitrosamine ( bbn ) or n-ethyl-n- ( 4-hydroxybutyl ) nitrosamine ( ehbn ) ( 0.025 % bbn or 0.021 % ehbn ) in the drinking water to male f344 rats for 20 weeks to determine whether urinary ph changes affect the carcinogenicity of bbn or ehbn .
C0003968
l-ascorbic acid
C0887557
sodium