Aspergillus Niger Safety

Fermentation is a process where a microorganism is utilized as a factory to produce certain nutrients or other biologically useful substances for humans. The culture, environment, and feed can encourage production of various products including enzymes and organic acids that are commonly used in foods and supplements. Some molds are benign; think of Saccharomyces boulardii (related to the yeasts in bread or beer) or blue cheese. 

While Aspergillus niger is a black mold, it is not the black mold that contaminates homes. As with the enzymes produced by A. niger, inhalation of mold or enzymes is not healthy for the lungs, and precautions are taken during production. In addition, A. niger is considered GRAS (generally regarded as safe) by the FDA and has been used for a century to produce citric acid and enzymes. Enzymes produced by A. niger do not contain significant amounts of the culture after isolation and purification to USP monograph standards of purity. Just as milk does not contain a cow, enzymes produced by A. niger do not inherently contain black mold. 

The U.S EPA has reported: 

“Exposure to Aspergillus must be nearly universal but disease is rare. The physiological condition of the exposed individual thus appears to be of paramount importance. Patients exhibiting aspergillosis are generally immunocompromised, and thus susceptible to otherwise common and usually harmless microorganisms. Factors that may lead to immunosuppression include an underlying debilitating disease (e.g., chronic granulomatous diseases of childhood), chemotherapy, and the use of supraphysiological doses of adrenal corticosteroids (Bennett, 1980)…A. niger is not a significant human pathogen. Throughout years of use and widespread exposure to A. niger in the environment, there are only several reports of aspergillosis with A. niger, and in Nigeria, one report of a number of cases of otomycosis. There have been only several reports of allergic reactions, which are not uncommon for aspergilli in general, and not unique to A. niger. A. niger is capable of producing several mycotoxins. However, mycotoxin production appears to be controlled by the conditions of fermentation.”  

EPA’s Final risk assessment for Aspergillus niger https://www.epa.gov/sites/production/files/2015-09/documents/fra006.pdf

https://pubmed.ncbi.nlm.nih.gov/12172605/