Location: Children's Nutrition Research CenterTitle: Construction of an N-nitroso database for assessing dietary intake Author
Submitted to: Journal of Food Composition and Analysis
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/12/2009
Publication Date: 1/12/2009
Citation: Stuff, J.E., Goh, E.T., Barrera, S.L., Bondy, M.L., Forman, M.R. 2009. Construction of an N-nitroso database for assessing dietary intake. Journal of Food Composition and Analysis. 22(Suppl 1):S42-S47. Interpretive Summary: N-nitroso compounds are present in micro quantities in foods,and are known to cause cancer in animals and humans. In the past, a systematic organization of levels of N-nitroso compounds in food sources had not been assembled in a database, and this study created this N-nitroso database. Now these values of N-nitroso compounds in food sources can be used by researchers to determine their cancer risk in epidemiological studies, and describe their intake by population groups surveyed in national nutrition surveys. If results show a risk for their intake, appropriate recommendations and interventions to reduce N-nitroso intake can be made. To initiate database development, an extensive review of all scientific literature, reports, and publications was assembled that reported one or more chemical analyses of N-nitroso compounds in a food source consumed by humans. The final research core database consisted of 4301 entries for 23 N-nitroso compounds, for 500 foods, from 47 references. From these, values were weighted to produce a representative value of each N-nitroso compound for the foods. Once assembled, we applied the database to estimate N-nitroso compounds in food sources reported as consumed in a Food Frequency questionnaire.
Technical Abstract: Dietary N-nitroso compounds are carcinogens synthesized during food processing from two main classes of precursors, oxides of nitrogen and amines or amides. Quantification of the dietary intake of N-nitroso compounds is significant to human cancers, including those of the stomach and upper gastro-intestinal tract, colon, and brain. Previous studies investigating these cancers primarily used proxy estimates of N-nitroso intake and not a full and complete database. In this report, we describe the development of a database to be used in conjunction with a food frequency questionnaire (FFQ) or 24 h dietary records. Published analytical data for N-nitroso compounds were compiled and evaluated for inclusion in the database. The final database consisted of 23 different N-nitroso compounds for 500 foods from 39 different food subgroups. Next, database foods were matched to foods in a standard FFQ by imputation, or calculated value, or assumed zero. Using the FFQ modified with N-nitroso values, we evaluated the ability to compute N-nitroso intakes for a sample of healthy control subjects of cancer epidemiological studies. N-nitroso content of food items ranged from <0.01 mu g/100 g to 142 mu g/100 g and the richest sources were sausage, smoked meats, bacon, and luncheon meats. The database is useful to quantify N-nitroso intake for observational and epidemiological studies.