Mutagenicity of Extracts of Pickled Vegetables Collected in Linhsien County, a High-Incidence Area for Esophageal Cancer in Northern China,

Abstract

Extracts of pickled vegetables commonly consumed in Linhsien County, a high-incidence area for esophageal cancer in Northern China, were studied for mutagenicity. The liquid residue from ethereal extracts produced a dose-dependent increase of mutants in Salmonella typhimurium TA98 and TA100 strains; mutagenicity required the presence of a fortified liver microsomal activation system induced by Aroclor 1254 in adult male BO VI inbred rats. An amount of extract equivalent to 2.8 g fresh pickled vegetables produced sixfold (75 revertants/g) and twofold (45 revertants/g) increases in revertant frequencies in strains TA98 and TA100, respectively. Roussin's red methyl ester, a tetranitroso compound; [(NO)₂Fe(CH₃S)]₂, not previously reported to occur in nature, was isolated and identified from the ethereal extracts. The synthetic compound was mutagenic in strain TA100 in the presence of a liver activation system, producing 25 revertants/μmol. Findings on the presence of mutagenic compounds in pickled vegetables were discussed in relation to their possible etiologic role in cancer of the esophagus in Linhsien County.