Epidemiology of gastric cancer in Chile: II - nitrate exposures and stomach cancer frequency

Abstract

Armijo R [Division of Epidemiology, School of Public Health, University of California, Los Angeles, CA 90024, USA], Gonzalez A, Orellana M, Coulson AH, Sayre JW and Detels R. The epidemiology of gastric cancer in Chile: II Nitrate exposures and stomach cancer frequency. International Journal of Epidemiology 1981, 10: 57-62.Nitrate levels in urine and nitrite levels in saliva were determined in school children 11-13 years of age in 2 areas of high stomach cancer mortality located in central Chile and in 2 areas of low stomach cancer mortality located at the extremes of Chile. Levels of both nitrates and nitrites were concurrently determined in selected vegetables obtained in these 4 study areas. Levels of nitrates were significantly higher in the urine of schoolchildren and in vegetables obtained from the northern low-risk area. Levels of nitrites were similar in saliva specimens from all 4 areas, but levels in vegetables were inconsistent. These results are apparently incompatible with