Issue: Among grains and other field crops, an important

food safety concern is the risk of contamination by mycotoxins, a toxic byproduct of mold infestations affecting as

much as one-quarter of global food and feed crop output.

Food contaminated with mycotoxins can cause sometimesfatal acute illness and is associated with increased cancer

risk from longer term exposure. To protect consumers

from these health risks, many countries, including the

United States, have adopted regulations to limit exposure

to mycotoxins, often taking the form of product standards.

However, diverging perceptions of tolerable health risks

have led to widely varying standards among different

national or multilateral agencies. The appropriate balance

between addressing food safety concerns and limiting disruptions of trade is a contentious issue, with important

economic consequences. How much do mycotoxin regulations vary internationally? To what extent do mycotoxin

hazards and regulations affect international trade and what

are the economic costs? What steps can be taken to mitigate trade disruptions? 

Background: Concerns about human health arise when

grains and other field crops are found to contain unsafe

chemicals, additives, or other contaminants. Many countries have established sanitary and phytosanitary (SPS)

regulations to protect consumers from these health risks,

while seeking to balance health benefits with the potential

trade disruptions, economic losses, and market uncertainties that regulations can cause. Among grains and other

field crops, perhaps the most prevalent—if publicly unrecognized—source of food-related health risks are naturally

occurring poisonous substances called mycotoxins.

Consuming grains or other foods contaminated with certain mycotoxins can increase cancer risk and suppress the

immune system, among other health problems. 

As with many public food safety regulations, domestic and

trade regimes governing mycotoxins in most countries take

the form of product, rather than process, standards. That

is, tolerance levels for the amount of mycotoxin in a product are established, rather than regulating the production or

treatment of the commodity along the marketing chain.

The United States began regulating the concentration of

mycotoxins in food and feed in 1968. At least 77 countries

now have regulations for mycotoxins, and the number

grew significantly from the mid-1980s to mid-1990s. The

range of tolerance levels in these countries varies widely.

In 1996, for example, 48 countries had established tolerance levels for total aflatoxins (a type of mycotoxin) in

food—up from 30 in 1987—with standards ranging from 0

parts per billion (ppb) to 50 ppb. For the 21 countries with

standards on animal feeds, the tolerance levels ranged

from 0 ppb to 1,000 ppb (see table).

Enforcing these limitations naturally imposes costs on

domestic producers and consumers (e.g., of monitoring,

testing, destroying the crop or diverting it to a lower valued use). At the same time, when the cost and benefit

analyses—or risk assessments—underlying domestic regulations lead countries to set different tolerance standards,

these divergent standards can also affect producers in other

countries, disrupt trade, and result in trade disputes. 

The idea that there can be a uniform assessment of how to

balance human safety concerns with “proportionate”

impacts on trade can be both problematic and controversial. Some argue that exceptionally strict food safety regulations impose unfair economic, and even safety, burdens

on lower income food-exporting countries. The argument

is that such standards limit export opportunities because

compliance is either too costly or unachievable given the

lack of technical capacity, infrastructure, and experience

with food hazards management. 

Findings: The economic losses associated with mycotoxin

contamination are difficult to assess, and no comprehensive analysis of the costs to U.S. and foreign crop/livestock producers is available. However, with an estimated

25 to 50 percent of the world’s food crops affected by

United States

Department of

Agriculture

Economic 

Research

Service

Issues in Diet, Safety, and Health / Agriculture Information Bulletin Number 789-6 February 2004

Mycotoxin Regulations 

Implications for International

Agricultural Trade

Erik Dohlman, edohlman@ers.usda.gov, (202) 694-5308
2 Economic Research Service / USDA

Mycotoxin Regulations: Implications for International Agricultural Trade/ AIB-789-6

mycotoxins, the economic costs are likely to be considerable. Numerous reports focusing on different countries/

regions, commodities, toxins, and cost categories (e.g.,

costs of regulations, testing, production loss, trade losses)

offer some indication of these losses. For example, the

Council for Agricultural Science and Technology (2003)

estimated that crop losses (to corn, wheat, and peanuts)

from mycotoxin contamination in the United States

amount to $932 million annually, in addition to losses

averaging $466 million annually from regulatory enforcement, testing, and other quality control measures.

Wilson and Otsuki (2001) estimated that, for a group of 46

countries—including the United States—the adoption of a

uniform aflatoxin standard based on international (Codex

Alimentarius) guidelines would increase trade of cereals

(grains) and nuts by more than $6 billion, or more than 50

percent, compared with the divergent standards in effect

during 1998. Potential export gains to the United States

amounted to $700 million. Also, since less developed

countries generally have less stringent mycotoxin standards, those that conduct trade with one another will lose

more export opportunities than will developed countries.

Trade disputes over regulatory standards on mycotoxins

could persist. First, mycotoxin contamination is recognized as an unavoidable risk. Many factors that influence

the level of contamination in cereals and grains are environmentally related—such as weather and insect infestation—and are therefore difficult to control. Second, perceptions of tolerable health risks are not likely to narrow

significantly in the near future since they appear to hinge

largely on the level of economic development and the susceptibility of a nation’s crops to contamination. Finally,

under the precautionary principle, some countries may set

new standards on certain mycotoxins for which scientific

evidence of a health risk is unclear. 

One strategy to lower both the health risks and the economic costs associated with mycotoxins is to instruct food

producers and handlers on strategies to minimize mycotoxin contamination, and to encourage the adoption of

process-based guidelines such as Good Agricultural

Practices (GAPs) before harvest and good manufacturing

practices (GMPs) after harvest. These strategies would

minimize risk throughout the production, handling, and

processing chain, and can complement product standards. 

An effective long-term strategy for controlling and monitoring mycotoxin risks in countries most susceptible to the

problem (due to climate or poor storage facilities) will

likely require technical assistance from public agencies

and private actors abiding by quality control measures and

GAP/GMP principles.

Information Sources:

For full text, see Dohlman, E. “Mycotoxin Hazards and

Regulations: Impacts on Food and Animal Feed Crop

Trade,” chapter 6 in International Trade and Food Safety:

Economic Theory and Case Studies. J. Buzby (ed.).

USDA, Econ. Res. Serv., AER-828, Nov. 2003.

www.ers.usda.gov/publications/aer828/

Medians and ranges of maximum aflatoxin tolerance levels and number of countries 

with regulations (1987, 1996)

1987 1996

No. of No. of

Category Median Range countries Median Range countries

— Parts per billion — Number — Parts per billion — Number

B1 in foodstuffs 4 0-50 29 4 0-30 33

B1+B2+G1+G2 in foodstuffs 7 0-50 30 8 0-50 48

B1 in foodstuffs for children 0.2 0-5.0 4 0.3 0-5.0 5

M1 in milk 0.05 0-1.0 13 0.05 0-1.0 17

B1 in feedstuffs 30 5-1,000 16 20 5-1,000 19

B1+B2+G1+G2 in feedstuffs 50 10-1,000 8 50 0-1,000 21

Note: B1, B2, G1, G2, and M1 are subcategories of aflatoxins.

Source: Adapted from Van Egmond, Hans, “Worldwide Regulations for Mycotoxins.” Third Joint FAO/WHO/UNEP International Conference on

Mycotoxins. MYC-CONF/99/8a, March 1999.

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