Ochratoxin A is a mycotoxin produced by several Aspergillus and Penicillium species, notably Aspergillus ochraceus and Penicillium verrucosum. It turns up both in stored food commodities and in water-damaged buildings, and like all mycotoxins it is a chemical residue that outlasts the mold that made it.
Where it is found
In food, ochratoxin A is associated with stored cereals, coffee, dried fruit, wine and some spices, and it is regulated in many countries. In buildings, the producing species grow on damp materials, in dust and in HVAC systems.
Because both Aspergillus and Penicillium are extremely common indoor genera, the species capable of producing it are frequently present in water-damaged structures — though presence of the species does not by itself mean the toxin was produced.
What research has focused on
Most toxicological work on ochratoxin A concerns kidney effects, established chiefly in animal studies, which is why it is often described as nephrotoxic. Regulatory limits in food derive from that body of work.
How that maps onto low-level indoor environmental exposure is not settled, and we will not pretend otherwise or offer you an interpretation. If exposure is a health concern for you, that is a conversation for a qualified practitioner.
Why it stays after the mold is gone
Remediation removes the organism and the material it grew in. Ochratoxin A is a molecule that settled elsewhere in the building while that was happening. Nothing in the standard remediation sequence targets it, and standard clearance testing measures spore counts, which is a different thing entirely.
This gap between "the mold is gone" and "the building is clear" is the most common reason a properly remediated house still does not feel right.
Removal
- HEPA vacuuming and surface cleaning for hard surfaces.
- Enzymatic breakdown for surfaces and contents together — the stage MycotoxinKlear is built for.
- Laundering with an enzyme detergent for fabrics, since standard detergent washes around residue rather than degrading it. FabricKlear covers this.
- Disposal for porous items that stayed wet.
Common questions
What produces ochratoxin A?
Several Aspergillus and Penicillium species, notably Aspergillus ochraceus and Penicillium verrucosum.
Is ochratoxin A found indoors?
Yes. The producing species grow on damp building materials, in dust and in HVAC systems.
Does remediation remove ochratoxin?
Not by design. Remediation targets the organism; the residue requires separate treatment of surfaces and contents.
How is it detected?
Dust sampling with laboratory analysis. Standard spore-count air testing does not detect mycotoxins.
See also: what is a mycotoxin.
