Instagram · May 26, 2026
Aspergillus niger fungus on onions can produce harmful toxins, experts advise caution
The video discusses that black spots on onions can be caused by Aspergillus niger, a fungus that may produce harmful toxins, and advises on proper cleaning methods for onions.
What's right
What's wrong
Breakdown
The claim is fully supported by the provided web context. Multiple sources confirm that the black spots or mold on onions are often caused by the fungus Aspergillus niger (References 1, 2, 6, 9, 10, 11, 12).
These sources also state that Aspergillus niger can produce mycotoxins which are harmful to health, particularly the liver, and can cause toxicity if consumed in large amounts or over long periods (References 1, 3, 4, 7). Health experts and the provided context advise on proper handling, including washing onions, peeling off affected layers, and discarding heavily contaminated onions (References 1, 2, 4, 5).
The use of salt water or vinegar for cleaning is also mentioned as a way to reduce surface contamination (Reference 1). The distinction between fungus and dirt is also supported, as the black discoloration is identified as fungal growth (References 2, 9, 11, 12). [1][2][3]