Aspergillus niger is a fungus and one of the most common species of the genus Aspergillus. It causes black mould on certain types of fruit and vegetables. Although often found in the passages of the outer ear, Aspergillus niger is not likely to cause disease. It is used in the manufacture of citric acid (E330) and gluconic acid (E574) and has been assessed as acceptable for daily intake by the World Health Organisation. They report that the fungus is a common contaminant of food but is not pathogenic to humans.