Alternaria spp.

Health Effects

Has been associated with hypersensitivity pneumonitis. Common cause of extrinsic asthma (immediate-type hypersensitivity: type I) (26). May be related to bakers asthma (17). Acute symptoms include edema and bronchiospasms, chronic cases may develop pulmonary emphysema (26).


Very common allergen (7) with an IgE mediated response (17).

Growth Indoors

Often found in carpets, textiles, (175), and on horizontal surfaces (often on window frames) (17).

Outdoor Location

Found in soil, (175) seed, and plants (6). Common in outdoor samples.

Potential Toxin Production

Alternaria alternata is capable of producing tenuazonic acid and other toxic metabolites which may be associated with disease in humans or animals (17).

Spore Size

Conidia dimensions 18-83 x 7-18(5). Large spore size 20-200 x 7-18 suggest that the spores from this fungi will be deposited in the nose, mouth, and upper respiratory tract (17).

Water Activity

0.88 (32)

Mold Reference Key

Abbreviation  Reference
Aw Water Activity (Equilibrium relative humidity/100)
E Paul Ellringer
MAC McGregor Pearce - personal experience
NC Neil Carlson - personal experience
(1-27) Refer to Fungal Reference page


N. Carlson 9/92; Rev. 4/93, 7/93, 9/93, 1/94, 2/94,2/95,4/95, 5/96, 7/96