Dietary Exposure to Nitrites and Nitrosamines in a Spanish Population

Abstract

P-212 Introduction: Humans are exposed to N-Nitrosocompounds (NOC) from diet, tobacco smoke and other environmental sources, as well as from endogenous synthesis. Diet has been identified as the major source of exogenous exposure. Due to potential health effects of nitrites and nitrosamines (NA), it is necessary an accurate assessment of their intake in the general population. Subjects and Setting: A study was conducted within the Spanish cohort of the European Prospective Investigation in Cancer and Nutrition (EPIC) to assess the intake and food sources of these compounds in the Spanish adult population. The study included 41446 health volunteers, aged 29–69 years from North and South Spanish regions. Usual food intake was estimated by personal interview trough a computerized version of a dietary questionnaire. Dietary intakes of nitrites and NDMA were estimated based on the information compiled recently in a food database (FDB).1 Since considerably more information is available for NDMA than for other NA found in foods we decided to estimate only the dietary intake to NDMA. Results and discussion: The estimated geometric means were 0.994 mg/day and 0.114 μg/day for nitrites and N-nitrosodimethylamine (NDMA) respectively. For both compounds was observed a positive trend in relation to caloric intake. Dietary NDMA showed relation with age and sex adjusted by energy, while nitrites with vitamin C (p<0.001). The food groups that more contribute to the intake were: meat products, cereals, vegetables and fruits for nitrites; and processed meat, beer, cheese and broiled fish for NDMA. Although, current and past smokers have a high levels of NDMA from tobacco smoking, they have been identified as higher consumers dietary NDMA. Also, they have a low intake of Vitamin C (inhibitor of endogenous nitrosation). Conclusions: In the present study within the current and past smokers groups, those that have a low intake of vitamin C (inhibitor of endogenous nitrosation) have also a high dietary NDMA exposure. Thus, they could be considered as a high risk population. Additional investigations in order to identify food sources of endogenous NOC are needed for an accurate assessment of total dietary exposure.