Total Mercury in infant food: a contribution to EFSA’ s collection of chemical contaminants occurrence data

Abstract publicado em: "Book of Abstracts" do "12th Meeting on Food Chemistry – Bridging traditional and novel foods: composition, structure and functionality”,(S4-PP29).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 (Hg22+) 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. The collection of analytical data on food and feed is an important task of the European Food Safety Authority - EFSA and an essential component in risk assessment. Following the statements of Regulation (EC) n.º 178/2002 Member States (MS) have the responsibility to report to EFSA data produced under the official control of food and feed. 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. To monitor total mercury occurrence in infant foods, we measured the concentrations of Hg in 31 different products from 4 food groups available on Portuguese market (10 purees and fruit juices, 12 cereals, 5 milks and 4 prepared meals). These samples were collected during 2012. 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). We obtained a range 0.9 to 8.6 μg/Kg, for the limit of quantification. Analytical quality control was achieved using certified reference material BCR 151 skim milk powder and NIST 1566b oyster tissue. More than 95 % of the results were below the limit of detection (LOD) or the limit of quantification (LOQ). However, 3.2 % of the results revealed low concentrations. Fish and other seafood had the highest values of total mercury in comparison to all other food categories. Analysis of this data indicated that the average intake of mercury from fish and seafood products were below the tolerable weekly intakes established by JECFA, occasionally the mean intakes may be near to this level (1.6 μg/kg body weight). Although fish is an important part of a healthy diet as it provides important nutrients, it´s recommend that young children select fish from a wide range of species, without giving undue preference to large predatory fish such as swordfish and tuna. Due to their place in the food chain, these fish are likely to contain higher levels of methylmercury than other fish species