Aflatoxins in food
Aflatoxins are mycotoxins produced by two species of Aspergillus, a fungus which is especially found in areas with hot and humid climates. Since aflatoxins are known to be genotoxic and carcinogenic, exposure through food should be kept as low as possible.
Aflatoxins can occur in foods, such as groundnuts, treenuts, maize, rice, figs and other dried foods, spices and crude vegetable oils, and cocoa beans, as a result of fungal contamination before and after harvest.
Several types of aflatoxins are produced in nature. Aflatoxin B1 is the most common in food and amongst the most potent genotoxic and carcinogenic aflatoxins. It is produced both by Aspergillus flavus and Aspergillus parasiticus. Aflatoxin M1 is a major metabolite of aflatoxin B1 in humans and animals, which may be present in milk from animals fed with aflatoxin B1 contaminated feed.
The European Union introduced measures to minimise the presence of aflatoxins in different foodstuffs. Maximum levels of aflatoxins are laid down in Commission Regulation (EC) No 1881/2006. Products exceeding the maximum levels should not be placed on the market in the EU. Directive 2002/32/EC lays down maximum levels for aflatoxins B1 in feed materials.
Methods of sampling and analysis for the official control of mycotoxins, including aflatoxins, are laid down in Commission Regulation No 401/2006. This ensures that the same sampling criteria intended for the control of mycotoxin content in food are applied to the same products by the competent authorities throughout the EU and that certain performance criteria, such as recovery and precision, are fulfilled.
In 2008, the Codex Alimentarius set a maximum level of 10 µg/kg total aflatoxins in ready-to-eat almonds, hazelnuts, and pistachios at a level higher than that currently in force in the EU (4 µg/kg total aflatoxins). Currently the European Commission and Member States are discussing the alignment of EU legislation for these nuts with the Codex Alimentarius decision. In addition, discussions will take place to align the new proposed maximum levels for all tree nuts.
In 2007 EFSA’s scientific Panel on contaminants in the food chain (CONTAM) provided risk managers with the scientific basis necessary to decide on the proposal of the Codex Alimentarius on setting maximum levels of aflatoxins in ready-to-eat almonds, hazelnuts and pistachios higher than those currently in place in Europe.
In an opinion adopted in January 2007, the CONTAM Panel concluded that increasing the current EU maximum levels of 4 µg/kg total aflatoxins in these three nuts to 8 or 10 µg/kg total afatoxins would have minor effects on the estimated dietary exposure, cancer risk and calculated margin of exposure. The Panel also concluded that exposure to aflatoxins from all food sources should be kept as low as reasonably achievable because aflatoxins are genotoxic and carcinogenic.
Moreover, the data indicated that the reduction of total dietary exposure to aflatoxins could be achieved by reducing the number of highly contaminated foods reaching the market and reducing exposure from contaminated food sources other than almonds, hazelnuts and pistachios.
In June 2009 the European Commission asked EFSA to assess the effect on public health of an increase of the maximum level for total aflatoxins from 4 µg/kg to 10 µg/kg allowed for tree nuts other than almonds, hazelnuts and pistachios (e.g. Brazil nuts and cashews). This would facilitate the enforcement of the maximum levels, in particular as regards mixtures of nuts.
The Panel concluded that public health would not be adversely affected by increasing the levels for total aflatoxins from 4 µg/kg to 8 or 10 µg/kg for all tree nuts. However, the Panel reiterated its previous conclusions regarding the importance of reducing the number of highly contaminated foods reaching the market.
In order to estimate human exposure in these two assessments, EFSA took into consideration occurrence data submitted by 20 Member States and third parties in 2006, as well as food consumption data obtained from the GEMS/Food Consumption Clusters Diets of the World Health Organisation, based on data of the Food and Agriculture Organisation.
In June 2009 EFSA launched a call for proposals to study the potential increase in aflatoxin B1 in cereals in the EU as a result of climate change. The project will gather and analyse data on aflatoxin B1 in order to build predictive models, define scenarios and create maps highlighting potential future contamination of cereal crops. The results will help to inform any future work in this area by EFSA and give an indication of potential emerging food contamination by mycotoxins in the EU due to climate change.
In 2004, EFSA’s CONTAM Panel also adopted an opinion related to aflatoxin B1 as an undesirable substance in animal feed. The Commission had asked EFSA to determine the exposure levels of aflatoxin B1 for dairy animals, in particular dairy cattle, above which the carry over from feed to milk would result in unacceptable levels of aflatoxin M1. The CONTAM Panel concluded that the current maximum levels of aflatoxin B1 in animal feed not only provided an adequate protection from adverse health effects in target animal species, but also prevented undesirable concentration of the metabolite aflatoxin M1 in milk. Among its recommendations, the Panel encouraged monitoring of the presence of aflatoxin B1 in imported feedstuffs and aflatoxin M1 in dairy milk.