Mercury content in foods a contribution to food risk assessment

Food risk assessment takes account of both toxicological information and estimates of dietary exposure of a population to the chemical substances in order to evaluate risks for public health (EFSA, FAO, & WHO 2011). To estimate dietary exposure accurately, it is essential to analyse foods as consumed for the presence and levels of chemical substances. Mercury is a metal that is released into the environment from both natural and anthropogenic sources. Once released, mercury undergoes a series of complex transformations and cycles between atmosphere, ocean and land. The three chemical forms of mercury are (i) elemental or metallic mercury (Hg0), (ii) inorganic mercury (mercurous (Hg2 2+) and mercuric (Hg2+) cations) and (iii) organic mercury. Methylmercury is by far the most common form of organic mercury in the food chain. The European Food Safety Authority (EFSA) has established Tolerable Weekly Intakes (TWIs), or ‘safe levels’, intended to protect consumers from adverse health effects posed by the possible presence of the main forms of mercury found in food: methylmercury and inorganic mercury.On this basis, Member States, research institutions, academia and any other stakeholders are invited to submit occurrence data on these contaminants. Following these Commission Recommendations, Member States are requested to encourage the active involvement of food and feed business operators on the submission of available data on contaminants in food/feed to EFSA. In this study 117 different samples from 10 food groups according to the FoodEx Level 1, a pan- European food classification system, were analyse to determine the amount of total mercury. The samples were collected during October 2013-May 2015. Determination was carried in compliance with ISO standard 17025. Total mercury (Hg) was determined in a Direct Mercury Analyser DMA 80 (Milestone Inc.; CT, USA), according to United States Environmental Protection Agency test method 7473 (USEPA, 2007) [2]. We obtained different limits of quantification, according matrices, in a range 0.5 μg/Kg (grapes and fruit salad) to 13.8 μg/Kg (popcorn). Analytical quality control was achieved using certified reference material NIST 1566b oyster tissue and BCR 151 skim milk powder. More than 72 % of the results were below the limit of quantification (LOQ). However, 27.4% of the results revealed measurable concentration of mercury. Fish and other seafood and a composite food containing fish had the highest values of total mercury (between 2.9 and 574 μg/Kg of sample) in comparison to all other food categories. Analysis of this data indicated that the average intake of mercury from fish and seafood products can be near the tolerable weekly intakes established by JECFA (1.6 μg/kg body weight). This study provide baseline information on the analytical data on the chemical substances of interest to performed, a dietary exposure assessment to determine whether this substance pose a risk to the public health, i.e. whether intakes exceed the toxicological limits