Mannanase is an enzyme, which breaks down polysaccharides, which consist of mannose. The enzyme is used in detergents, where it enables the removal of sugar-containing (mannose-containing) stains.
The EU generally considers enzymes to be potential respiratory allergens, which pose a work environment risk relative to causing allergies. The EU, however, simultaneously considers the risk of allergies to be minimal relative to ordinary consumer usage of enzyme-containing detergents etc.
Low concentrations of the enzyme may, therefore, be used in detergents, which have been certified by Asthma-Allergy Denmark.
The low concentrations equally ensure that inhalation due to dispensing, as well as residual concentrations of dissolved detergents after wash do not cause irritation or allergies.
A study from 2010 including data material from 15,765 people gathered over a 40 year period as well as a literature examination showed that 37 people had developed allergies towards enzymes (i.e. antibodies). There was not found symptoms or any direct linkage to laundry or detergent exposure. Most cases had risen before 1977 and thus with people, who had been exposed to high exposure concentrations. The clinical test showed that the occurrence of enzyme specific allergies in the general population is very rare (0.126% since 1977).