Genetically modified enzymes used in food, perfumes, medicine and cleaning products are “potent allergens” and should be tested like other potentially hazardous chemicals, experts have said.

There has been an explosion in the use of enzymes to boost flavours and aromas, including in low-fat foods, helping to create a sector worth about $10bn (£7.7bn), according to a study published in Occupational & Environmental Medicine.

Some techniques allow the products to be labelled as “natural” in Europe and the US but the researchers warn that genetically engineering the enzyme protein may change its allergenic properties.

They measured specific antibodies to artificially created enzymes in blood samples from 813 workers, employed in the food, drinks, chemicals, detergents and pharmaceutical industries.

The employees had worked in their respective industries for periods ranging from three months to 10 years and had been exposed to an average of two to four genetically modified enzymes in the workplace.