Mesophilic · Extended-panel species

Aspergillus carbonarius

Major ochratoxin A producer of wine grapes and dried fruits. Black Aspergillus section Nigri; offered on extended panels to fill the OTA producer gap left by the standard 36.

Extended panelMesophilic · Aw ≥ 0.82

Moisture niche · where this species can grow

XerophilicAw < 0.80
MesophilicAw 0.80–0.89
HydrophilicAw ≥ 0.90
Min Aw 0.82
← Drier conditions toleratedRequires liquid water →
Minimum Aw
0.82
EPA reference (GM)
< 0.4 SE/mgMeklin AHHS threshold
Mycotoxin profile
3+ documented
Ecological role
Secondary colonizer

The < 0.4 SE/mg reference value is Meklin 2004's AHHS exclusion threshold: the paper retained species whose geometric mean was at least 2 spores per 5 mg dust (≈ 0.4 spores/mg) and eliminated the rest. This species was measured across the 1,096-home AHHS sample and characterized below that threshold, used here as a conservative ceiling on its true GM, not a percentile band. A detected value of X SE/mg implies an elevation factor of at least X ÷ 0.4 over the EPA reference, a lower bound, since the true GM is below 0.4. See the 82-species story for the math.

About Aspergillus carbonarius

Aspergillus carbonarius is the principal black Aspergillus producer of ochratoxin A on warm-climate fruit substrates. It is the dominant OTA route in wine grapes globally and a significant producer on coffee, cocoa, and dried fruits. Detection on a residential extended panel typically reflects food-source contamination or warm-environment substrates rather than structural water damage.

Taxonomy

Ascomycota → Eurotiomycetes → Eurotiales → Aspergillaceae → Aspergillus section Nigri

Ecology and habitat

A. carbonarius is a warm-climate Aspergillus, ecologically distinct from A. ochraceus (the other major Aspergillus OTA producer, associated with stored commodities such as coffee, cocoa, and spices). Major substrates are wine grapes, raisins, dried figs, coffee, and cocoa. Geographic distribution favors Mediterranean and tropical regions where warm post-harvest storage conditions favor OTA production.

Indoor relevance

Indoor relevance is principally through food-source substrates rather than building materials: wine cellars, dried-fruit storage, and warm-climate residential pantries are the typical contexts. Less commonly associated with structural water damage than the other indoor OTA producers (A. ochraceus).

Cardinal physiology

Minimum water activity for growth: Aw 0.82[2]. Growth across 10–42 °C with optimum 30–35 °C. OTA production has a higher Aw threshold (≥ 0.92) and a lower temperature optimum (15–20 °C) than vegetative growth. Production is favored at conditions intermediate between growth optimum and inhibition.

OTA production at Aw ≥ 0.92; optimum near 0.95 and 15–20 °C. Production temperature optimum is well below the growth temperature optimum.

Secondary metabolites

The principal mycotoxin is ochratoxin A. A. carbonarius is a more consistent OTA producer per isolate than A. niger, and its contribution to the global cereal/grape OTA load is substantial. Some strains additionally produce naphtho-γ-pyrones and rare fumonisin B2.

Compounds documented as produced by Aspergillus carbonarius (presence and quantity vary by chemotype, strain, and substrate):

Ochratoxin A (primary)Naphtho-γ-pyronesFumonisin B2 (some strains)

DNA-based detection of a mycotoxin-producing species in household dust does not directly establish exposure to that mycotoxin at any specific concentration.

Lab availability

Some commercial dust testing labs offer this species as an extended-panel option. Specific lab coverage changes over time: check with your laboratory for current panel options.

Related

Ochratoxin APrimary mycotoxin produced by this species.Aspergillus ochraceusOther major Aspergillus OTA producer; stored commodities (coffee, cocoa, spices).Aspergillus nigerClosely related black Aspergillus on the standard ERMI.Beyond the 36

References

  1. Meklin T, Haugland RA, Reponen T, Varma M, Lummus Z, Bernstein D, Wymer LJ, Vesper SJ. Quantitative PCR analysis of house dust can reveal abnormal mold conditions. J Environ Monit. 2004;6(7):615–620.
  2. Pitt JI, Hocking AD. Fungi and Food Spoilage. 3rd ed. New York: Springer; 2009.
  3. Pardo E, Ramos AJ, Sanchis V, Marín S. Modelling of effects of water activity and temperature on germination and growth of ochratoxigenic isolates of Aspergillus ochraceus on a green coffee-based medium. Food Addit Contam. 2006;23:398–410.
  4. International Agency for Research on Cancer. IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Vol. 56: Some Naturally Occurring Substances. Lyon: IARC; 1993.