title: N-nitroso compounds in two nitrosated food products in southwest Korea.
abstract: Gastric cancer is the commonest malignant neoplasm in Southwest Korea. The possibility of carcinogenic dietary factors led to the investigation of exposure to N-nitroso compound precursors among residents of the City of Chonju and of two outlying rural townships in North Cholla Province. Two traditional and widely consumed home-prepared food products, salted pickled cabbage (kimchi) and salted seafood sauce (chut-kal) were analysed (a) for nitrite, nitrate, total secondary amines and pH in these food products prior to nitrite incubation and (b) for volatile nitrosamines and total N-nitroso compounds before and after incubation with nitrite in simulated human stomach conditions. Nitrate levels were significantly higher in kimchi (median 1550 mg/kg) than in chut-kal (median 140 mg/kg) (P < 0.001). Secondary amine levels in non-nitrosated samples of kimchi (median 5.5 mg/kg) were significantly lower than secondary amine levels in non-nitrosated chut-kal (median 56 mg/kg) (P = < 0.001). Analyses of nitrite-incubated kimchi revealed high levels of total N-nitroso compounds (median 1173 micrograms/kg); the increase with nitrosation was significant (P = 0.001). The concentration of N-nitroso compounds in nitrite-incubated kimchi was significantly greater than that found in nitrite-incubated chut-kal (P = 0.015). The combination of high levels of nitrate in the kimchi, the demonstration of high levels of total N-nitroso compounds in this food after nitrosation, and the volume of kimchi consumed in the traditional diet suggest that salted pickled cabbage may play a role in gastric carcinogenesis in Southwest Korea.
authors: Presbyterian Medical Center, Chonju, Korea.
authors: D J
authors: DJ
authors: Seel
authors: T
authors: T
authors: Kawabata
authors: M
authors: M
authors: Nakamura
authors: T
authors: T
authors: Ishibashi
authors: M
authors: M
authors: Hamano
authors: M
authors: M
authors: Mashimo
authors: S H
authors: SH
authors: Shin
authors: K
authors: K
authors: Sakamoto
authors: E C
authors: EC
authors: Jhee
authors: S
authors: S
authors: Watanabe
mesh_terms: D000588:Amines / Q000032:analysis; D001205:Ascorbic Acid / Q000032:analysis; D001937:Brassica; D005285:Fermentation; D005504:Food Analysis; D005511:Food Handling; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007723:Korea; D009566:Nitrates / Q000032:analysis; D009573:Nitrites / Q000032:analysis; D015538:Nitrosation; D009603:Nitroso Compounds / Q000032:analysis*; D017747:Seafood; D012982:Sodium, Dietary / Q000008:administration & dosage; D012987:Soil / Q000032:analysis; D014881:Water Supply / Q000032:analysis
chemical_list: D000588:Amines; D009566:Nitrates; D009573:Nitrites; D009603:Nitroso Compounds; D012982:Sodium, Dietary; D012987:Soil; D001205:Ascorbic Acid