Several people in Australia, the UK and the US have reported severe reactions to the fungal-based meat substitute.

The Center for Science in the Public Interest (CSPI) is calling on Australian officials to prohibit the sale of Quorn brand meat substitutes after several consumers have reported allergic reactions ranging from nausea, vomiting and diarrhea to anaphylactic symptoms. Quorn is a meat substitute based on the fungus, Fusarium veneatum, which according to CSPI, is a mold discovered in a 1960s British dirt sample. Quorn brand food products have been on sale in the UK for 25 years and in the US since 2001. CSPI has also fought the approval of these products in the US and UK.

Early Quorn marketing materials sought to convey a relationship with more desirable fungi, such as mushrooms and morels, says a CSPI release. But according to a statement made by an expert in fungal taxonomy to CSPI, “mushrooms are as distantly related to Quorn’s fungus as humans are to jellyfish.”

Nevertheless, a number of consumers report the same allergic effects when eating Quorn products, and symptoms appear within an hour or two of eating the fungal-based food, according to CSPI. The meat substitute is used in artificial chicken patties and nuggets, turkey-like cylindrical roasts and meat-free analogs of several British delicacies like “Cornish pasties” and “Toad in the Hole.”

The use of myco-protein as an ingredient used in Quorn brand foods was originally submitted to FDA as GRAS (generally recognized as safe) by Marlow Foods, a subsidiary of AstraZeneca Ltd., on November 30, 2001. Marlow Foods had been petitioning FDA since 1986 for the myco-protein to be used as a food additive.

As with many food allergens-peanuts or shellfish, for example-not everyone is susceptible to ill effects when eating Quorn brand products. In 2002, the UK-based Guardian reported that 100 people in 14.6 million in the UK and Europe were affected by the food, this according to tallies from Marlow Foods. CSPI says it has been collecting adverse reaction reports online, and the total numbers “more than 1,500 to date.”