The investigation of relationships between dietary exposures and disease risks requires accurate and complete databases of food composition information. Although numerous epidemiologic studies have identified inverse relationships between carotenoid rich foods and various cancers and several other diseases, data are lacking on the content of the individual carotenoids in foods. The overall purpose of this project is to provide a comprehensive database of values for five carotenoids of interest to cancer research: alpha-carotene, beta-carotene, beta- cryptoxanthin, lycopene, and lutein/zeaxanthin. Foods that are major contributors to the US diet for each of the five carotenoids will be given highest priority for analysis. Selected foods will include single component foods, as well as frequently consumed commercial mixtures. These foods will be sampled based on a nationwide sampling plan and recent market research data. Samples of low fat foods will be chemically analyzed using existing procedures at USDA's Nutrient Composition Laboratory (NCL). These procedures will be modified to permit analysis of the individual carotenoids in higher fat foods. The nutrient database maintained at the University of Minnesota's Nutrition Coordinating Center (NCC) will be expanded to include the five carotenoids. Software will be developed to automate the calculation of imputed carotenoid values for several thousand entries in the NCC brand name products database. The accuracy of the NCC database and nutrient calculation procedures will be evaluated by comparing analytic values provided by NCL with NCC's calculated values for commercial mixed dishes and typical daily menus. The database and calculation software resulting from this project will provide a tool for the accurate assessment of individual carotenoid intakes and will further investigations of relationships between carotenoid exposures and risks of various cancers and other diseases.