Everything you need to know
Aflatoxins are among the most potent naturally occurring carcinogens known to science. Produced by Aspergillus flavus and Aspergillus parasiticus, these mycotoxins commonly contaminate peanuts, tree nuts, corn, dried spices, and herbal supplements. Understanding where they come from and how to test for them is critical for food safety compliance.
What are aflatoxins and which are regulated?
Aflatoxins are difuranocoumarin mycotoxins produced primarily by Aspergillus flavus and Aspergillus parasiticus. There are four primary regulated aflatoxins: Aflatoxin B1 (AFB1) — the most toxic and most common; a Group 1 human carcinogen (IARC). Aflatoxin B2 (AFB2) — less prevalent than B1; also carcinogenic. Aflatoxin G1 (AFG1) — the second most toxic; named for its green fluorescence. Aflatoxin G2 (AFG2) — least toxic of the four. Regulatory limits typically apply to "total aflatoxins" (sum of all four) and sometimes to AFB1 specifically (EU).
What is the FDA action level for aflatoxins?
FDA's action level for total aflatoxins (B1 + B2 + G1 + G2) is 20 parts per billion (ppb) in food and feed intended for human consumption. This applies to products including peanut butter, tree nuts, dried fruits, and grain products. FDA can take enforcement action — seizure, recall, or injunction — against products exceeding this level. The EU's limits are stricter: 4 ppb total aflatoxins and 2 ppb AFB1 for most foods, with even stricter limits for baby food and infant formula.
Which foods and supplements have the highest aflatoxin risk?
The highest-risk commodities for aflatoxin contamination are: Peanuts and peanut products (peanut butter, peanut flour, peanut oil); Dried red spices (chili pepper, paprika, cayenne, red pepper flakes); Tree nuts (almonds, pistachios, Brazil nuts, walnuts); Corn and corn products; Dried figs and dates; Turmeric and ginger; Dried herbal teas; Supplement ingredients derived from any of the above. Aflatoxin contamination increases dramatically when commodities are stored in warm, humid conditions with poor air circulation.
Does cooking or processing destroy aflatoxins?
Aflatoxins are remarkably heat-stable and resistant to typical food processing temperatures. Roasting peanuts at 150–160°C reduces aflatoxin levels by 50–80%, but does not eliminate them. Extrusion and autoclaving can further reduce levels, but contaminated raw material remains contaminated even after processing. This is why testing the finished product — not just assuming processing removes the risk — is critical. EU and FDA limits apply to finished consumer products.
What is the LC-MS/MS method for aflatoxin testing?
The gold standard analytical method for aflatoxin quantitation is LC-MS/MS (liquid chromatography-tandem mass spectrometry). The process involves: (1) extraction of aflatoxins from the sample matrix using solvent; (2) optional immunoaffinity column cleanup to remove matrix interferences; (3) LC separation of the four aflatoxin analytes; (4) tandem MS detection with specific precursor/product ion transitions for each aflatoxin. LC-MS/MS provides confirmed quantitative results with detection limits well below 0.5 ppb — far below the FDA 20 ppb action level — making it suitable for both compliance testing and export to strict EU markets.
How much sample is needed for aflatoxin testing?
Aflatoxin contamination is often heterogeneous — it may occur in hotspots within a lot. For this reason, sampling strategy matters as much as analytical method. We typically require 5–10 grams of finished product or raw material per analysis. For regulatory compliance of a large lot, consider sending multiple subsamples from different parts of the lot. We grind solid samples (spices, nuts, capsules) in-house to ensure a homogeneous subsample. Order aflatoxin testing for your supplement.