Food Additives & Contaminants
ISSN: 0265-203X (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/tfac19
Rationales for the establishment of limits and regulations for mycotoxins L. Stoloff , H. P. van Egmond & D. L. Park To cite this article: L. Stoloff , H. P. van Egmond & D. L. Park (1991) Rationales for the establishment of limits and regulations for mycotoxins, Food Additives & Contaminants, 8:2, 213-221, DOI: 10.1080/02652039109373971 To link to this article: http://dx.doi.org/10.1080/02652039109373971
Published online: 10 Jan 2009.
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Citing articles: 15 View citing articles
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Date: 10 November 2015, At: 16:41
FOOD ADDITIVES AND CONTAMINANTS, 1991, VOL. 8, NO. 2, 2 1 3 - 2 2 2
Rationales for the establishment of limits and regulations for mycotoxins L. STOLOFF†, H. P. VAN EGMOND‡ and D. L. PARK§¶ †Consultant, 13208 Bellevue St, Silver Spring, MD 20904, USA; ‡National Institute of Public Health and Environmental Protection, PO Box 1, 3720 BA Bilthoven, The Netherlands; §University of Arizona, 309 Shantz Bldg., Tucson, AZ 85721, USA
Downloaded by [University of Florida] at 16:41 10 November 2015
(Received 12 March 1990; revised 29 October 1990; accepted 30 October 1990) Although 50 countries have enacted or proposed regulations for control of aflatoxins in food or feed, and 15 of these countries also have regulations for permitted levels of contamination by other mycotoxins, very few countries have formally presented the rationale for the need to regulate, or for the selection of a particular maximum tolerated level. After several successive inquiries, information concerning the rationale for regulation was obtained from 21 countries. Most of the responses concerned limits for aflatoxin in food, and most of these were based on a vague, unsupported statement of the carcinogenic risk for humans. There was a general consensus that exposure to a potential human carcinogen that could not be totally avoided should be limited to the lowest practical level; the definition of practicality depended on whether the country was an importer or producer of the potentially contaminated commodity. A claim to a hazard evaluation was made by six countries (Canada, Belgium, India, United Kingdom, United States, Switzerland) without providing specifics; and one country, South Africa, referred to a risk determination. The most comprehensive rationale for any mycotoxin regulation was provided by the United States in support of limits for aflatoxin in specific animal feedstuffs. The responses provided no rationale for setting limits for other mycotoxins; but scholarly risk assessments for zearalenone and ochratoxin A have been published by Canadian government scientists, and a symposium presentation provides the information that in Norway patulin is regulated for quality control purposes only. It is apparent that, in most countries, either the scientific basis for regulation of mycotoxins is nonexistent, or the science has not been fully utilized. For a common approach to the control of mycotoxin hazards, access to the best available scientific data, and agreement on its interpretation, now appear to be the most important initial steps. Keywords: aflatoxin, deoxynivalenol, diacetoxyscirpenol, hazard analysis, mycotoxin, ochratoxin, patulin, regulation, risk management, T-2 toxin, tolerance, zearalenone
Introduction
All nations have the right and duty to protect their citizens and livestock from harmful substances in food or feed. In an ideal situation—when all the parameters of toxicity, occurrence, marketing and technology of the problem are known—the potential harm from various amounts of the substance in food or feed is examined in relation to other factors (e.g. agronomic, technological, marketing, economic, political) associated with the problem. A strategy is then devised to manage the risk at a point in the marketing or distribution system that will provide the most ^To whom correspondence should be addressed. 0265-203X/91 $3.00 © 1991 Taylor & Francis Ltd.
Downloaded by [University of Florida] at 16:41 10 November 2015
214
L. Stoloff et al.
effective protection, and a maximum tolerated level for the harmful substance at that point in the system is established. In today's jargon these operations are known as hazard assessment, risk determination, risk management, and the overall operations as risk analysis. The maximum tolerated level and point of control are normally embodied in some regulation for formal endorsement. The regulation of mycotoxins has developed under less than ideal circumstances. The pressure to control mycotoxins, and aflatoxin in particular, had occurred before an adequate knowledge of the risk factors and control technology had been developed. In the face of a potential cancer risk, and uncertainty about most of the toxicity, contamination and technology parameters, the first control recommendations (by the US Food and Drug Administration (FDA) and the UN Protein Advisory Group) in 1969 were based on prudence and the need to maintain a supply of a cheap, nutritious foodstuff, namely peanuts (Stoloff 1980a, Protein Advisory Group 1969). By 1987, 50 countries had enacted or proposed legislation for aflatoxins in peanuts and/or other foodstuffs, 14 countries had enacted or proposed legislation for aflatoxin Mi in dairy products, 35 for aflatoxins in feedstuffs, and 15 countries had enacted legislation for other mycotoxins: patulin, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, chetomin, stachybotryotoxin, and phomopsin (van Egmond, 1989). In the years after 1969 there was a very considerable volume of information published on risk factors for harm from mycotoxins, particularly aflatoxins, but very few countries, to our knowledge, have formally presented a rationale for the need to regulate, or for their selection of a particular maximum tolerated level. There have been a few unofficial presentations of rationales by knowledgeable individuals, but for the most part one can only speculate on the reason for a particular regulatory action: was it a formal risk analysis; was it a political position that no detectable amount of a harmful substance could be permitted in food; or was it an action to accommodate a trading partner or some commercial standard? Survey procedure
As part of a letter sent by the U.S. authors in September 1987 for updating of our compilation of worldwide regulations for mycotoxins, each government agency contacted was asked for a 'brief statement on the rationale that was the basis for setting those [mycotoxin] limits, and if there is additional information concerning the distribution and hazards supporting the regulations established for mycotoxins'. Of the responses received, only two addressed the question of rationale. A followup letter in March 1988 was more specific. It noted that 'since 1969, the results of a considerable amount of research on mycotoxins, particularly aflatoxin, have been published, providing some answers needed for the scientific basis of mycotoxin regulation'. The letter asked for assistance 'in determining the extent to which published information has been used', and requested that the respondent 'indicate whether the decision to regulate was economic or political, or was based on a perceived hazard to health. If economic or political, what was the basis for selection of the level at which to regulate? If hazard to health was perceived, what published or unpublished information was relied on for a determination of the hazard, the risk, and the control strategy, including the maximum level allowed?' Because the response from government contacts to the rationale question was still unsatisfactory, an attempt was made to obtain the answer from scientific sources. In January 1989 a letter was sent to colleagues involved in mycotoxin research in every country
Limits and regulations for mycotoxins
215
where one or another of the authors had ever developed a contact. This time the specific questions were posed in the form of statements to be checked, and amplified upon, if checked. This paper is a compilation of all responses, plus our own contributions for our respective countries, and our assessment of the apparent foundations for mycotoxin regulations. Survey results
Downloaded by [University of Florida] at 16:41 10 November 2015
There were responses of some sort from 32 countries; some type of response to the rationale question was received from only 18 countries. With the addition of The Netherlands and the US and a symposium presentation on Norwegian regulations of mycotoxins, there is rationale information from 21 of the 50 countries that regulate mycotoxins. Limits for aflatoxin in food Most of the rationale responses concerned limits for aflatoxin in food (table 1). Two countries, South Africa and The Netherlands, referred to a risk determination. South Africa based the determination on the results of an epidemiological study (Van Rensburg et al. 1974) of liver cancer rate and aflatoxin intake in a part of the region with a high liver cancer rate. The conclusion of a later study (Van Rensburg et al. 1985) in the same area had apparently not been considered for a redetermination of the risk. The Netherlands based the risk determination for the development of liver cancer after a single dose of aflatoxin Bi on the study of Scotto et al. (1975), and for a subchronic intake on the study of Wogan et al. (1974). The rationale for this approach was that the number of contaminated peanuts in a lot is very low, but that the contamination level within a kernel can be very high. This results in practice in accidental acute intake of aflatoxin (for instance when products with contaminated whole or broken peanuts are consumed), or an accidental chronic intake of aflatoxin (for instance when products with contaminated milled peanuts, like peanut butter, are consumed). Four countries (Belgium, Switzerland, United Kingdom, United States) based their perception of the hazard on reviews of the literature, two countries (Switzerland, United Kingdom) on reviews and recommendations of 'expert' groups. One country (India) relied on the advice of an FAO-WHO-UNICEF panel (Protein Advisory Group 1969), that considered the risk from aflatoxin in a protein supplement (peanut meal) that was being offered in the 1960s for kwashiorkor therapy, and extended the recommended limit in peanut meal to be used as a protein supplement to all foods. Most responding countries offered a vague, unsupported statement of the carcinogenic risk to humans from aflatoxin, some (Canada, United Kingdom, United States) considering it prudent to regulate a carcinogen for test animals as if it were a carcinogen for humans. Only Canada referred to the conclusion of a Working Group of the International Agency for Research on Cancer (IARC 1987) that there is sufficient evidence to consider aflatoxin a probable human carcinogen. There is general consensus that exposure to a potential human carcinogen that could not be totally avoided should be limited to the lowest practical level. For countries importing the potentially contaminated commodity, that level is established by the limitations of the analytical methods selected. An exception is the United Kingdom, where the controlling concept is 'technically feasible'. For countries producing the commodity, agronomic and technological considerations generally determine the limits within that country except for exports, where the requirements of
Table 1. Rationale for setting limits for aflatoxin in food.
Downloaded by [University of Florida] at 16:41 10 November 2015
Limits set by Perceived hazard Country
Vague statement
Austria Australia
X X
Belgium Canada Dominican Republic FR of Germany Finland German DR Hungary India Kenya Netherlands
Review of literature
Risk analysis
Analytical method
Practical considerations
X X
See note
X X
X X X X X
X
X
X X
Political
X X
Trade requirements
X
Refer to WHO Techn. Rpt. Series 759, 1987 Guided by other European countries and international trade Export limits set by trading partners Domestic limits based on Protein Advisory Group (1969)
X
X
Notes Practical considerations apply to peanuts, a domestic crop No specifics Coordinates with US
X
See note
Based on rat carcinogenicity studies (Wogan et al. 1974, Hsieh et al. 1984)
X X X
See note X
X
Switzerland
See note
United Kingdom
See note
United States Zimbabwe
Other
X
See note
Nigeria Senegal South Africa Spain
Economic factors
X X
X X X
See note
The topic of 'aflatoxin' in Codex Alimentarius committees has not progressed beyond the discussion stage.
From epidemiological study (Van Rensburg et al. 1974) Refers to Codex Alimentarius* and judgement of other European countries Based on advice of 'experts' from Institute of Toxicology, Zurich Based on recommendations of Food Advisory Committee See Park and Stoloff (1989) Based on Codex Atimentarius* recommendations and levels accepted in other countries
SU
Limits and regulations for mycotoxins
217
Downloaded by [University of Florida] at 16:41 10 November 2015
trading partners prevail. The level in the United States, where major commodities subject to contamination are produced, was originally based on the limitations of the methods available to prove aflatoxin identity (Park and Stoloff 1989), a legal necessity, but as methods have improved, the original level has been retained for practical agronomic and technological considerations. Canada, a major US trading partner, coordinates with the US in this regard. Limits for aflatoxin in feed For aflatoxin in feed, the members of the European Economic Community (EEC) are bound by the limits set by the EEC Commission. In the published directives on the fixing of maximum permitted levels for undesirable substances and products in feeding stuffs (Commission of the European Communities 1974, 1983) and on establishing Community methods of analysis for the official control of feeding stuffs (Commission of the European Communities 1976) there is no mention of how the limits were determined. One can only guess from the numbers that there were practical considerations of feedstuff availability, except for dairy feeds, where the concern about aflatoxin Mi in milk and milk products was probably a determining factor, limited by the lowest level of aflatoxin Bi that could be detected by the analytical method. In the 1983 directive there was a statement that the maximum permitted level for aflatoxin Bi for complementary dairy feeds was reduced from 20 to lOg/kg to prevent, where possible, residues of aflatoxin Mi in milk. In the US political and economic pressures forced a rethinking of the rationales for aflatoxin limits in corn and cottonseed meal, the two domestic feedstuffs most susceptible to aflatoxin contamination (Park and Pohland 1986, Park and Stoloff 1989, FDA 1989). The original limits applied to both food and feed. The revisions for feed took into consideration the level that would allow use of the major portion of the contaminated crop and its relation to a toxic dose in the ingesting animal, as well as the possibility of measurable aflatoxin residues in the edible animal tissues (meat, milk and eggs). The revised levels are specific as to commodity and animal, and are based on a thorough study of the data on contamination incidence, toxicity of aflatoxin to each target animal, and the relation of aflatoxin level in feed to aflatoxin level in edible tissue. A criterion of no detectable aflatoxin in edible tissue (•
ISSN: 0265-203X (Print) (Online) Journal homepage: http://www.tandfonline.com/loi/tfac19
Rationales for the establishment of limits and regulations for mycotoxins L. Stoloff , H. P. van Egmond & D. L. Park To cite this article: L. Stoloff , H. P. van Egmond & D. L. Park (1991) Rationales for the establishment of limits and regulations for mycotoxins, Food Additives & Contaminants, 8:2, 213-221, DOI: 10.1080/02652039109373971 To link to this article: http://dx.doi.org/10.1080/02652039109373971
Published online: 10 Jan 2009.
Submit your article to this journal
Article views: 33
View related articles
Citing articles: 15 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=tfac20 Download by: [University of Florida]
Date: 10 November 2015, At: 16:41
FOOD ADDITIVES AND CONTAMINANTS, 1991, VOL. 8, NO. 2, 2 1 3 - 2 2 2
Rationales for the establishment of limits and regulations for mycotoxins L. STOLOFF†, H. P. VAN EGMOND‡ and D. L. PARK§¶ †Consultant, 13208 Bellevue St, Silver Spring, MD 20904, USA; ‡National Institute of Public Health and Environmental Protection, PO Box 1, 3720 BA Bilthoven, The Netherlands; §University of Arizona, 309 Shantz Bldg., Tucson, AZ 85721, USA
Downloaded by [University of Florida] at 16:41 10 November 2015
(Received 12 March 1990; revised 29 October 1990; accepted 30 October 1990) Although 50 countries have enacted or proposed regulations for control of aflatoxins in food or feed, and 15 of these countries also have regulations for permitted levels of contamination by other mycotoxins, very few countries have formally presented the rationale for the need to regulate, or for the selection of a particular maximum tolerated level. After several successive inquiries, information concerning the rationale for regulation was obtained from 21 countries. Most of the responses concerned limits for aflatoxin in food, and most of these were based on a vague, unsupported statement of the carcinogenic risk for humans. There was a general consensus that exposure to a potential human carcinogen that could not be totally avoided should be limited to the lowest practical level; the definition of practicality depended on whether the country was an importer or producer of the potentially contaminated commodity. A claim to a hazard evaluation was made by six countries (Canada, Belgium, India, United Kingdom, United States, Switzerland) without providing specifics; and one country, South Africa, referred to a risk determination. The most comprehensive rationale for any mycotoxin regulation was provided by the United States in support of limits for aflatoxin in specific animal feedstuffs. The responses provided no rationale for setting limits for other mycotoxins; but scholarly risk assessments for zearalenone and ochratoxin A have been published by Canadian government scientists, and a symposium presentation provides the information that in Norway patulin is regulated for quality control purposes only. It is apparent that, in most countries, either the scientific basis for regulation of mycotoxins is nonexistent, or the science has not been fully utilized. For a common approach to the control of mycotoxin hazards, access to the best available scientific data, and agreement on its interpretation, now appear to be the most important initial steps. Keywords: aflatoxin, deoxynivalenol, diacetoxyscirpenol, hazard analysis, mycotoxin, ochratoxin, patulin, regulation, risk management, T-2 toxin, tolerance, zearalenone
Introduction
All nations have the right and duty to protect their citizens and livestock from harmful substances in food or feed. In an ideal situation—when all the parameters of toxicity, occurrence, marketing and technology of the problem are known—the potential harm from various amounts of the substance in food or feed is examined in relation to other factors (e.g. agronomic, technological, marketing, economic, political) associated with the problem. A strategy is then devised to manage the risk at a point in the marketing or distribution system that will provide the most ^To whom correspondence should be addressed. 0265-203X/91 $3.00 © 1991 Taylor & Francis Ltd.
Downloaded by [University of Florida] at 16:41 10 November 2015
214
L. Stoloff et al.
effective protection, and a maximum tolerated level for the harmful substance at that point in the system is established. In today's jargon these operations are known as hazard assessment, risk determination, risk management, and the overall operations as risk analysis. The maximum tolerated level and point of control are normally embodied in some regulation for formal endorsement. The regulation of mycotoxins has developed under less than ideal circumstances. The pressure to control mycotoxins, and aflatoxin in particular, had occurred before an adequate knowledge of the risk factors and control technology had been developed. In the face of a potential cancer risk, and uncertainty about most of the toxicity, contamination and technology parameters, the first control recommendations (by the US Food and Drug Administration (FDA) and the UN Protein Advisory Group) in 1969 were based on prudence and the need to maintain a supply of a cheap, nutritious foodstuff, namely peanuts (Stoloff 1980a, Protein Advisory Group 1969). By 1987, 50 countries had enacted or proposed legislation for aflatoxins in peanuts and/or other foodstuffs, 14 countries had enacted or proposed legislation for aflatoxin Mi in dairy products, 35 for aflatoxins in feedstuffs, and 15 countries had enacted legislation for other mycotoxins: patulin, ochratoxin A, deoxynivalenol, zearalenone, T-2 toxin, chetomin, stachybotryotoxin, and phomopsin (van Egmond, 1989). In the years after 1969 there was a very considerable volume of information published on risk factors for harm from mycotoxins, particularly aflatoxins, but very few countries, to our knowledge, have formally presented a rationale for the need to regulate, or for their selection of a particular maximum tolerated level. There have been a few unofficial presentations of rationales by knowledgeable individuals, but for the most part one can only speculate on the reason for a particular regulatory action: was it a formal risk analysis; was it a political position that no detectable amount of a harmful substance could be permitted in food; or was it an action to accommodate a trading partner or some commercial standard? Survey procedure
As part of a letter sent by the U.S. authors in September 1987 for updating of our compilation of worldwide regulations for mycotoxins, each government agency contacted was asked for a 'brief statement on the rationale that was the basis for setting those [mycotoxin] limits, and if there is additional information concerning the distribution and hazards supporting the regulations established for mycotoxins'. Of the responses received, only two addressed the question of rationale. A followup letter in March 1988 was more specific. It noted that 'since 1969, the results of a considerable amount of research on mycotoxins, particularly aflatoxin, have been published, providing some answers needed for the scientific basis of mycotoxin regulation'. The letter asked for assistance 'in determining the extent to which published information has been used', and requested that the respondent 'indicate whether the decision to regulate was economic or political, or was based on a perceived hazard to health. If economic or political, what was the basis for selection of the level at which to regulate? If hazard to health was perceived, what published or unpublished information was relied on for a determination of the hazard, the risk, and the control strategy, including the maximum level allowed?' Because the response from government contacts to the rationale question was still unsatisfactory, an attempt was made to obtain the answer from scientific sources. In January 1989 a letter was sent to colleagues involved in mycotoxin research in every country
Limits and regulations for mycotoxins
215
where one or another of the authors had ever developed a contact. This time the specific questions were posed in the form of statements to be checked, and amplified upon, if checked. This paper is a compilation of all responses, plus our own contributions for our respective countries, and our assessment of the apparent foundations for mycotoxin regulations. Survey results
Downloaded by [University of Florida] at 16:41 10 November 2015
There were responses of some sort from 32 countries; some type of response to the rationale question was received from only 18 countries. With the addition of The Netherlands and the US and a symposium presentation on Norwegian regulations of mycotoxins, there is rationale information from 21 of the 50 countries that regulate mycotoxins. Limits for aflatoxin in food Most of the rationale responses concerned limits for aflatoxin in food (table 1). Two countries, South Africa and The Netherlands, referred to a risk determination. South Africa based the determination on the results of an epidemiological study (Van Rensburg et al. 1974) of liver cancer rate and aflatoxin intake in a part of the region with a high liver cancer rate. The conclusion of a later study (Van Rensburg et al. 1985) in the same area had apparently not been considered for a redetermination of the risk. The Netherlands based the risk determination for the development of liver cancer after a single dose of aflatoxin Bi on the study of Scotto et al. (1975), and for a subchronic intake on the study of Wogan et al. (1974). The rationale for this approach was that the number of contaminated peanuts in a lot is very low, but that the contamination level within a kernel can be very high. This results in practice in accidental acute intake of aflatoxin (for instance when products with contaminated whole or broken peanuts are consumed), or an accidental chronic intake of aflatoxin (for instance when products with contaminated milled peanuts, like peanut butter, are consumed). Four countries (Belgium, Switzerland, United Kingdom, United States) based their perception of the hazard on reviews of the literature, two countries (Switzerland, United Kingdom) on reviews and recommendations of 'expert' groups. One country (India) relied on the advice of an FAO-WHO-UNICEF panel (Protein Advisory Group 1969), that considered the risk from aflatoxin in a protein supplement (peanut meal) that was being offered in the 1960s for kwashiorkor therapy, and extended the recommended limit in peanut meal to be used as a protein supplement to all foods. Most responding countries offered a vague, unsupported statement of the carcinogenic risk to humans from aflatoxin, some (Canada, United Kingdom, United States) considering it prudent to regulate a carcinogen for test animals as if it were a carcinogen for humans. Only Canada referred to the conclusion of a Working Group of the International Agency for Research on Cancer (IARC 1987) that there is sufficient evidence to consider aflatoxin a probable human carcinogen. There is general consensus that exposure to a potential human carcinogen that could not be totally avoided should be limited to the lowest practical level. For countries importing the potentially contaminated commodity, that level is established by the limitations of the analytical methods selected. An exception is the United Kingdom, where the controlling concept is 'technically feasible'. For countries producing the commodity, agronomic and technological considerations generally determine the limits within that country except for exports, where the requirements of
Table 1. Rationale for setting limits for aflatoxin in food.
Downloaded by [University of Florida] at 16:41 10 November 2015
Limits set by Perceived hazard Country
Vague statement
Austria Australia
X X
Belgium Canada Dominican Republic FR of Germany Finland German DR Hungary India Kenya Netherlands
Review of literature
Risk analysis
Analytical method
Practical considerations
X X
See note
X X
X X X X X
X
X
X X
Political
X X
Trade requirements
X
Refer to WHO Techn. Rpt. Series 759, 1987 Guided by other European countries and international trade Export limits set by trading partners Domestic limits based on Protein Advisory Group (1969)
X
X
Notes Practical considerations apply to peanuts, a domestic crop No specifics Coordinates with US
X
See note
Based on rat carcinogenicity studies (Wogan et al. 1974, Hsieh et al. 1984)
X X X
See note X
X
Switzerland
See note
United Kingdom
See note
United States Zimbabwe
Other
X
See note
Nigeria Senegal South Africa Spain
Economic factors
X X
X X X
See note
The topic of 'aflatoxin' in Codex Alimentarius committees has not progressed beyond the discussion stage.
From epidemiological study (Van Rensburg et al. 1974) Refers to Codex Alimentarius* and judgement of other European countries Based on advice of 'experts' from Institute of Toxicology, Zurich Based on recommendations of Food Advisory Committee See Park and Stoloff (1989) Based on Codex Atimentarius* recommendations and levels accepted in other countries
SU
Limits and regulations for mycotoxins
217
Downloaded by [University of Florida] at 16:41 10 November 2015
trading partners prevail. The level in the United States, where major commodities subject to contamination are produced, was originally based on the limitations of the methods available to prove aflatoxin identity (Park and Stoloff 1989), a legal necessity, but as methods have improved, the original level has been retained for practical agronomic and technological considerations. Canada, a major US trading partner, coordinates with the US in this regard. Limits for aflatoxin in feed For aflatoxin in feed, the members of the European Economic Community (EEC) are bound by the limits set by the EEC Commission. In the published directives on the fixing of maximum permitted levels for undesirable substances and products in feeding stuffs (Commission of the European Communities 1974, 1983) and on establishing Community methods of analysis for the official control of feeding stuffs (Commission of the European Communities 1976) there is no mention of how the limits were determined. One can only guess from the numbers that there were practical considerations of feedstuff availability, except for dairy feeds, where the concern about aflatoxin Mi in milk and milk products was probably a determining factor, limited by the lowest level of aflatoxin Bi that could be detected by the analytical method. In the 1983 directive there was a statement that the maximum permitted level for aflatoxin Bi for complementary dairy feeds was reduced from 20 to lOg/kg to prevent, where possible, residues of aflatoxin Mi in milk. In the US political and economic pressures forced a rethinking of the rationales for aflatoxin limits in corn and cottonseed meal, the two domestic feedstuffs most susceptible to aflatoxin contamination (Park and Pohland 1986, Park and Stoloff 1989, FDA 1989). The original limits applied to both food and feed. The revisions for feed took into consideration the level that would allow use of the major portion of the contaminated crop and its relation to a toxic dose in the ingesting animal, as well as the possibility of measurable aflatoxin residues in the edible animal tissues (meat, milk and eggs). The revised levels are specific as to commodity and animal, and are based on a thorough study of the data on contamination incidence, toxicity of aflatoxin to each target animal, and the relation of aflatoxin level in feed to aflatoxin level in edible tissue. A criterion of no detectable aflatoxin in edible tissue (•
