policy briefs to government
in peanut butter
Unit, Medical Research Council, PO Box 19070,
Tygerberg, 7505 South Africa; tel. (021) 938-0290.
During May 2001 several
reports appeared in the news media in South Africa about the "poison
in the peanuts". These related to high levels of aflatoxin that were
allegedly found in peanut butter given to school children in the Eastern Cape
under the Primary Schools Nutrition Programme (PSNP). The PROMEC Unit of the
South African Medical Research Council (MRC), an internationally recognised
centre of excellence on toxins produced by fungi (mycotoxins), including aflatoxin,
decided to prepare this Policy Brief in order to clarify the issue and to
emphasise the serious health implications of supplementing the diet of school
children with peanut butter containing aflatoxin.
Staff members of the PROMEC
Unit are regularly invited to be expert consultants on food-borne toxins by
the World Health Organization (WHO) and the Food and Agriculture Organisation
of the United Nations (FAO). Unfortunately they were not consulted by the
South African Department of Health (DOH) when the PSNP, including peanut butter,
was launched in 1994. In fact, the PROMEC Unit first became aware of concerns
about the presence of aflatoxin in peanut butter used in the PSNP in February
1998 from consultants to and representatives of the Western Cape Department
of Health (WCDOH). Since then the PROMEC Unit has, on various occasions, held
meetings with representatives of WCDOH, peanut butter manufacturers and distributors,
and the Peninsula School Feeding Association about the occurrence and source
of aflatoxins in peanut butter, and problems in sampling and analysis of contaminated
foods and health implications. It transpired from these meetings that limited
budgets and personnel did not allow for adequate sampling and chemical analyses.
Although no funds were available for an expert investigation to be undertaken
by the PROMEC Unit, staff members presented several lectures to health authorities
about the risk of exposing school children to aflatoxin.
Mycotoxins (of which aflatoxin
is an example) are a group of secondary metabolites produced by fungi that
are natural contaminants of agricultural products such as peanuts. The toxicological
effects in animals have been known for a long time and have necessitated health
authorities worldwide to regulate mycotoxin levels in human food and animal
feed. The presence of mycotoxins in food is, however, often overlooked due
to public ignorance about their existence; lack of regulatory mechanisms;
dumping of food products in developing countries; and the introduction of
contaminated commodities into the human food chain during chronic food shortages
due to droughts, wars, political and economic instability, etc. Apart from
economic issues, ethical considerations also play a role during the manufacturing
process of food products using heavily contaminated commodities. Instead of
excluding these from the food process, unscrupulous manufacturers sometimes
dilute contaminated agricultural products such as peanuts with good-quality
products to an acceptable' level below the regulatory level, or market
them as such when no regulatory measures are enforced.
Aflatoxins, of which aflatoxin
B1 (AFB1) is the most important, are produced mainly by the fungus Aspergillus
flavus, that may grow on peanuts before or after harvesting and under poor
storage conditions. In 1993 the International Agency for Research on Cancer
(IARC) classified AFB1 and mixtures of aflatoxins as Group 1 carcinogens,
i.e. substances that can cause cancer in humans. Epidemiological studies of
human populations exposed to diets naturally contaminated with aflatoxins
revealed an association between the high incidence of liver cancer in Africa
and elsewhere and dietary intake of aflatoxins.
The tolerance levels of
aflatoxins in human foodstuffs are regulated worldwide and in South Africa
by Government Notice No. R 313 of 16 February 1990, Regulations Governing
Tolerances for Fungus-Produced Toxins in Foodstuffs. According to these regulations,
which are the responsibility of the DOH, the maximum legal level of total
aflatoxins in foodstuffs is 10 micrograms per kilogram, of which 5 micrograms
per kilogram (parts per billion) may be AFB1. According to several newspaper
reports, levels of 271,63 micrograms per kilogram of total aflatoxin and 165,05
micrograms per kilogram AFB1 were reported in peanut butter given to school
children in the Eastern Cape. These levels are approximately 30 times higher
than the legal limits.
At present it is not known
how these aflatoxin levels were determined and whether standardised sampling
procedures and chemical analytical techniques were applied. No data are available
for the other provinces, but it can only be assumed that the problem is not
restricted to the Eastern Cape but occurs everywhere in South Africa where
the PSNP is operational.
The question arises whether
the DOH considered the health aspects of aflatoxins in peanut butter at the
onset of the PSNP, or whether sufficient funds were allocated to enforce adequate
sampling and testing to safeguard a commodity intended to supplement the diet
of underprivileged school children. Newspaper reports indicate that 4,8 million
children are involved in the PSNP throughout South Africa, and that R472,8
million was allocated on the inception of the programme. The media further
indicated that the Nutrition Deputy Director of the Eastern Cape allegedly
"challenged anyone with information about illnesses caused by the peanut
butter to come forward". If this is quoted correctly, it is a most unfortunate
statement as this is not the issue here. Health implications of exposure to
aflatoxins can be divided into symptoms of acute poisoning (aflatoxicosis)
and chronic long-term health effects. Although aflatoxins have been implicated
in several episodes of acute human aflatoxicosis in various areas of the world,
these have been reported at contamination levels in the milligrams per kilogram
(parts per million) range, i.e. 1000 times higher than the legal tolerance
levels. However, the major health implication and area of considerable international
concern with respect to aflatoxin exposure is the cancer-causing (carcinogenic)
properties of AFB1, in that long-term exposure to low levels of the toxin
may cause liver cancer. This is the reason why aflatoxins are the most widely
and severely regulated of all the mycotoxins. It is of great concern that
the liver cancer risk increases significantly if a child suffering from hepatitis
B virus (HBV) infection consumes aflatoxin-containing foodstuffs, due to the
synergism between AFB1 and HBV in causing liver cancer.
The PSNP was launched
in 1994, and in areas with poor control over tender specifications and inadequate
enforcement of legal levels of aflatoxins in peanut butter during the past
7 years, may have increased the liver cancer risk in millions of previously
disadvantaged school children. The risk may have been increased markedly if
the children consumed the high levels of aflatoxins quoted in the news media,
and particularly if they are carriers and/or subsequently become infected
with HBV. An increase in liver cancer incidence in South Africa within 20
to 30 years from now is therefore possible.
- If the provision of
peanut butter sandwiches as an important nutritional supplement for school
children is to continue, rigorous quality control measures need to be enforced
by DOH on the manufacturers and distributors.
- Adequate funding should
be made available for surveillance by local health authorities to ensure
that suppliers comply with existing legislation aimed at reducing the risk
of exposure to aflatoxins.
- Cancelling Atoxic peanut
butter contracts@ and/or appointing new manufacturers or "consultants"
who know nothing about the aflatoxins will not solve the problem. Aflatoxin
contamination of peanuts and peanut butter can only be controlled if constant
vigilance is exercised by manufacturers and health authorities and when
appropriate sampling procedures and standardised chemical analytical techniques
are used. These analyses should be carried out with an expert mycotoxin
group such as the PROMEC Unit of the MRC as an independent and objective
- Closer collaboration
and communication between the DOH, PSNP, MRC and the PROMEC Unit is essential
to prevent a catastrophe such as the "poison in the peanuts" from
ever happening again.
Food safety is one of
the democratic rights of a healthy nation and should be fostered at all costs.
We would like to point out that the peanut butter used in the PSNP is quite
different from commercially available peanut butter, most of which is regularly
monitored for aflatoxin levels in South Africa.
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