Mycotoxin Legislation Worldwide
Introduction
The realisation that contaminants present in the food supply can present a hazard for human health has led increasingly to a call to understand their effects and to bring in controls as necessary. The impetus for this is greatest in the developed parts of the world where human life span has been extended as many long standing diseases have been eliminated or controlled, and nutrition and housing conditions improved. The reduction of human exposure to mycotoxins has thus become of higher priority in these areas so that statutory limits are usually the most stringent and tend to be revised downwards with time. In contrast, the priority for many developing countries is to control or eliminate disease and poverty, so regulations for mycotoxins have not been established so widely, or may be less stringent. Different limits in force in different parts of the world raise potential problems for international trade, usually to the detriment of the less developed Nations.
Review of mycotoxin regulations
The Food and Agriculture Organisation of the United Nations has been involved for many years in assisting developing countries in strengthening their capabilities for the prevention and control of contamination of foods by mycotoxins. In 1981, an overview of worldwide mycotoxin regulations was presented on behalf of an International Symposium on mycotoxins in Cairo (Sculler et al. 1983). This publication was updated in 1987 (van Egmond 1987) and more recently in 1995 (FAO 1997)- see Report for detailed tables of regulations at that time. At least 77 countries were then known to regulate mycotoxins (mostly for aflatoxins), and the Food and Agriculture Organisation is currently further updating information and this is expected to be published by the end of 2003 (van Egmond 2003- in press). This shows that at least 98 countries had regulations for food and/or animal feed in 2002, an increase of about 30% compared to 1995. The total population in these countries represents approximately 90% of the world’s inhabitants and information taken from an interim Report of this publication is summarised in the table. It is concluded that the regulatory requirements remain substantially different across many countries, although several regulations have been (or are being) harmonised in countries belonging to economic communities.
Provisional summary of regulations existing at the end of 2002
| Region | Countries with known regulations | % Inhabitants in Region | Most detailed regulations (and notes) |
Africa |
14 |
54 |
Morocco |
Asia/Oceania |
25 |
89 |
China and Iran (Harmonised regulations for Australia and New Zealand) |
Europe |
38 |
99 |
Several EU candidate countries (EU harmonising regulations) |
Latin America |
19 |
92 |
Uruguay |
North America |
2 |
100 |
Canada and USA |
The different limits and applications vary greatly in detail and the reader is advised to consult the review above or await its update. The following examples illustrate the complexity of the situation. The USA has a limit of 20 microgrammes/kg for total aflatoxins in foods for human consumption such as cereals and groundnuts, while those in the EC are 2 microgrammes/kg for aflatoxin B1 and 4 microgrammes/kg for total mycotoxins in cereals except maize, for which other values have been agreed (5 microgrammes/kg for aflatoxin B1 and 10 microgrammes/kg for total mycotoxins in maize to be subjected to sorting etc. before human consumption). The US FDA and EC have limits of 0.5 and 0.05 microgrammes/l respectively for aflatoxin M1 in milk and related products. For DON (deoxynivalenol), the US FDA advisory limit for wheat and wheat products for human consumption is 1000 microgrammes/kg, the EC is discussing the setting of limits such as 500 microgrammes/kg for cereal products for direct consumption, and 750 microgrammes/kg for raw cereals, while Germany has a limit of 350 microgrammes/kg for bread biscuits and pastries, Austria 500microgrammes/kg for raw wheat and rye with 750 microgrammes/kg for Durum wheat, Russia 1000 microgrammes/kg for hard wheat and Canada 2000 microgrammes/kg for uncleaned soft wheat.
Establishing a mycotoxin limit
Examination of all available toxicological data by a national or international organisation usually results in the estimation of a Provisional Maximum Tolerable Weekly or Daily Intake (PMTWI or PMTDI). Few data exist for human exposure to mycotoxins so these provisional figures are based mainly on animal studies. In principle these figures are derived from the No Observable Adverse Effect Level (NOEL) in animal studies divided by a factor of 100; 10 for extrapolation to humans and 10 for the variability between humans. Where the uncertainty is higher because of lack of data, higher safety factors may be used. This approach does not apply to genotoxic mycotoxins where the probability of an effect could never be eliminated completely without outlawing the food. Here it is recommended that the level of contaminant in the food should be reduced so as to be As Low As Reasonably Achievable (ALARA).
It is necessary to estimate human exposure to the target contaminant from all food sources. For example, for ochratoxin A in Europe this would include its occurrence in cereals, beer, coffee, dried fruit and a range of other foods. The limit set must also reflect the susceptibility of that commodity to ochratoxin A so that this can result in different limits for different foods.
The estimated PMTWI or PMTDI and the exposure data enable a maximum permissible limit to be estimated and set for a specific commodity or range of foodstuffs. Because dietary patterns vary considerably around the world, this complicates attempts to harmonise limits. A major dietary food consumed in one area that is highly susceptible to mycotoxin contamination will require a limit that will seem inappropriate or unnecessary for a population in a region that is a low consumer of that food.
Practical considerations in the operation of statutory limits
Rejection of consignments of a food commodity failing to comply with a statutory limit can have major financial implications or lead to international disputes. It is thus essential that test methods for measuring mycotoxins moving in international trade are reliable and accepted and fully backed up by appropriate documentation. A test method has 2 main components: sampling, and analysis. These are each covered in other fact sheets. Precise, sensitive and validated methods are available for most of the main mycotoxins. The EC now lays down criteria such as recovery, limit of quantification and relative standard deviation that a method must meet when used for statutory control purposes, rather than endorsing a specific method. The main problem area is thus arguably the sampling. The EC also lays down methods for sampling. These however are often demanding and onerous to carry out under real life situations. However, the specified number of incremental samples is statistically based on the expected distribution of mycotoxins in a bulk commodity in order that the end result has a high probability of being representative of the mean concentration of the whole consignment. Disputes over test results are most likely to be due to inadequate sampling procedures. There remains a need for development of simpler validated sampling protocols.
Costs associated with the introduction of regulations may be considerable. The UK Food Standards Agency carried out a Regulatory Impact Assessment for the UK prior to implementation of regulations for ochratoxin A within the EC. Two main costs were identified; those for enforcement that is the responsibility of Local Authorities and those for compliance (necessary for industry to show a ‘due diligence’ approach). A typical recurring cost for a dried vine fruit importer might equate to a value equivalent to 1% of annual turnover.
Conclusions
Regulations for mycotoxins vary considerably from region to region in the limits that have been set, the commodities to which these apply and the state of processing of the food material. Arrangements in place for enforcement of these limits vary greatly. These is now a welcome trend to setting limits at levels that can be justified and this is assisting in moves to harmonise regulations. Appropriate use of statutory or guideline limits can play a major role in reducing the exposure of the consumer to mycotoxins
References
Schuller, P. L., van Egmond, H. P. and Stoloff, L, 1983, Limits and regulations on mycotoxins. In: Proceedings of the International Symposium on Mycotoxins, 6-8 September 1981, Cairo, Egypt, pp. 111-129.
Van Egmond, H. P., 1987, Current limits for aflatoxins. Working papers Myc 87/9.1 and Myc 87/9.2. Second Joint FAO/WHO/UNEP International Conference on Mycotoxins, Bangladesh, Thailand, 28 September October 1987.
FAO, 1997, Worldwide regulations for mycotoxins 1995, A compendium. FAO Food and Nutrition Paper 64, Rome, 43 pages.
Van Egmond, H. P., 2003 (in preparation), Mycotoxins and Regulations: an update. Proceedings of the 2nd World Mycotoxin Forum, Nordwijk, The Netherlands, February 2003