Mycotoxins are naturally occurring chemicals produced by moulds growing on foodstuffs. Sterigmatocystin is a genotoxic carcinogen, which means it can cause cancer by damaging genetic material.
The study by the European Food Safety Authority (EFSA) of cereal grains, cereal products, beer and nuts from nine European countries detected the presence of the toxins in 10% of the samples.
More than 50% of these contaminated samples contained levels between limit of detection and 0.5μg/kg, which was within its proposed 1.5 μg/kg limit. In the other cases, levels were all in the range 0.5–6 μg/kg but with the only exception of oats (33μg/kg).
The EFSA panel on Contaminants in the Food Chain (CONTAM panel) however, said it had concluded in 2013 that it could not characterise the risk of sterigmatocystin for public health "due to lack of suitable data on the occurrence of sterigmatocystin".
Call for research
EFSA has now called for proposals aimed at the preparation of a study on its occurrence in food with “special focus on grains and grain based products for human consumption from different geographic regions in Europe.”
“Sterigmatocystin is a genotoxic carcinogen and therefore risk characterisation should be based on the margin of exposure (MOE) approach,” said the report and added that the absence of representative exposure data for Europe prevented the application of the MOE approach.
“Therefore the present call for proposals aims at the preparation of a study on the occurrence of sterigmatocystin in food… to possibly serve as supporting information to the CONTAM panel” for its future exposure assessment, the report added.
Results from the samples
The report said that sterigmatocystin is a mycotoxin that is usually found in grains, grain based products and other foods due to fungal infestation especially at the post-harvest stage.
A total of 1,259 samples of cereal grains, cereal products, beer and nuts were sampled between August 2013 and November 2014, originating from 45 countries, the report said.
Rice and oats were most prone to contamination with sterigmatocystin while the samples of beer and nuts were not found to be contaminated with it, the report added.