Aflatoxin Testing in Food and Feed

Aflatoxins are a group of toxic secondary metabolites produced primarily by Aspergillus flavus and Aspergillus parasiticus. These fungi thrive in warm and humid conditions and may contaminate crops both before harvest and during storage.
The principal aflatoxins of concern are:
‣ Aflatoxin B1 (AFB1)
‣ Aflatoxin B2 (AFB2)
‣ Aflatoxin G1 (AFG1)
‣ Aflatoxin G2 (AFG2)
Among these, aflatoxin B1 is the most prevalent and toxic.
Aflatoxins are most commonly associated with maize, groundnuts, tree nuts, oilseeds and products derived from these commodities. Contamination may also occur in compound feed and processed food products manufactured from contaminated raw materials.

The development of aflatoxins is strongly influenced by environmental conditions, particularly drought stress followed by elevated humidity. Inadequate drying and poor storage practices further increase the risk of fungal growth and toxin production.
High-risk commodities include:
‣ Maize and maize-based products
‣ Groundnuts and peanut products
‣ Tree nuts
‣ Oilseeds
‣ Animal feed and premixes
In dairy production systems, aflatoxin B1 present in feed can be metabolised to aflatoxin M1 and excreted in milk, creating an additional food safety concern.

Aflatoxins primarily target the liver and are recognised for their hepatotoxic effects.
In animals, exposure may result in:
‣ Reduced feed intake and growth
‣ Impaired immune response
‣ Liver damage
‣ Reduced productivity
‣ Increased susceptibility to secondary infections
In humans, aflatoxins are associated with acute toxicity at high exposure levels and chronic health effects following prolonged dietary intake. Aflatoxin B1 is classified as a human carcinogen and has been strongly linked to liver cancer, particularly in regions where exposure is not adequately controlled.
Because aflatoxins can enter the human food chain through both plant-derived foods and animal products, regulatory oversight is stringent in many jurisdictions.

Aflatoxin contamination is frequently heterogeneous within a batch, meaning toxin distribution may be uneven. Representative sampling is therefore essential to obtain reliable and meaningful results.
Analytical testing provides quantitative confirmation of aflatoxin levels and supports:
‣ Verification of compliance with regulatory limits
‣ Risk-based acceptance or rejection of raw materials
‣ Protection of consumer health
‣ Prevention of carry-over into animal-derived products
‣ Export certification and trade assurance
Modern LC-MS/MS methods allow accurate detection and quantification of individual aflatoxins at low concentration levels across a wide range of food and feed matrices.

Complete prevention of aflatoxin contamination is not always achievable, particularly in regions prone to drought and heat stress. Effective risk management therefore combines:
‣ Good agricultural practices
‣ Proper drying and storage
‣ Supplier monitoring
‣ Representative sampling
‣ Validated analytical testing
A structured monitoring programme is essential to control aflatoxin risk and maintain compliance across food, nut, oil and feed supply chains.