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Mycotoxins explained

The US Institute of Food Technologists has recently issued a Scientific Status Summary that gives an overview of the issue of mycotoxins in the international food industry (Murphy et al., 2006).

Mycotoxins are toxic chemical products formed by mould species including Penicillium, Aspergillus and Fusarium. These moulds can readily colonise food crops such as cereal grains, nuts and fruits, either in the field or post harvest. Consumption of foods produced from these commodities poses a potential risk to human health because the toxins are resistant to various food processes, including heat treatment. Mycotoxins rarely cause acute illness in developed countries, but long term consumption of low levels has been linked to disease.

The mycotoxins of concern to the international food industry are:

Mycotoxin	Of main concern in	Potential health effect
Patulin	Fruit juices, particularly apple	Genetic mutations
Ochratoxin A	Cereals, wine, coffee	Kidney disease
Zearalenone	Cereals	Endocrine system disruption
Aflatoxins	Peanuts, tree nuts and maize	Liver cancer
Trichothecenes	Cereals	Acute vomiting/ diarrhoea (high dose required)
Fumonisins	Maize	Kidney and liver disease

As harvest conditions in Australia are predominantly warm and dry, the threat of mycotoxin production in cereals is much lower here than in most other regions.

Contamination of Australian peanut crops by aflatoxins is an ongoing issue however, particularly when plants become drought stressed in seasons when there is low rainfall preceding harvest.

Despite reports of mycotoxin linked disease occurring overseas, there is no evidence that mycotoxins pose a particular health problem in Australia (Pitt and Tomaska, 2001; Pitt and Tomaska, 2002). Mycotoxins still pose a concern to Australian commodity exporters because they need to be aware of the requirements of importing countries which may differ from those in Australia. The European Union (EU) has set limits on the amounts of specific mycotoxins permissible in various foods and has stringent import testing programs in place. For example, the levels of Ochratoxin A currently allowed in foods imported into the EU can be found in the Official Journal of the European Union (EU, 2005).

Scientists at Food Science Australia have been conducting research into mycotoxins for the Australian food industry over many years. Their research has shown that competitive exclusion biocontrol by nontoxin producing Aspergillus species can be used to inhibit the growth of toxin producing species on peanut plants (Pitt and Hocking, 2006). Another study, conducted by a Cooperative Research Centre for Viticulture sponsored PhD student, found that Australian wines contained levels of Ochratoxin A well below limits set by the EU. Current research at Food Science Australia (funded by the Australian Food Safety Centre of Excellence), is assisting food processors with management of mycotoxin-producing Fusarium species.