Can this urinary mycotoxin pattern identify a building as the source?

At age 57, this urinary profile is best interpreted as evidence of recent absorbed mycotoxin exposure, not as a diagnosis of “mold toxicity” or proof that a particular home or workplace is responsible.

Exposure interpretation

• Dietary exposure is the most established explanation. Urinary ochratoxin A (OTA), citrinin (CIT), and its metabolite dihydrocitrinone (DH-CIT) are recognized markers of recent intake. In controlled human data, 32.9–70.8% of a citrinin dose was recovered in 24-hour urine as combined CIT+DH-CIT, supporting the importance of measuring both.
• Urinary aflatoxin and fumonisin findings also generally indicate recent ingestion, but interpretation is less specific for aflatoxin B2 and for fumonisins other than FB1. Results do not identify a particular food, quantify dose, or establish chronic exposure.

Route and source attribution

• Environmental exposure is biologically plausible where contaminated dust or air is relevant, but urinary mycotoxins are not route-specific. Concentrations vary with recent diet, metabolism, renal handling, and sampling time.
• Therefore, this pattern cannot distinguish food-derived exposure from inhalational or other environmental exposure, and it cannot identify a building, room, or workplace as the source.

Building assessment and mechanisms

• A defensible building-source assessment requires systematic evaluation for historical/current leaks, flooding, condensation, water intrusion, musty odours, visible mould, damaged materials, and ventilation/HVAC problems, with moisture assessment to locate active or concealed dampness.
• The practical target is correction of water intrusion and removal/remediation of mould-damaged materials; there is no universal health-based indoor microbial concentration threshold.

Bottom line

• The claim is well supported overall: this urine pattern can reflect recent dietary exposure and may be compatible with environmental contribution, but it cannot establish that a specific building caused exposure without a focused environmental assessment, ideally alongside dietary review and—when attribution is essential—paired environmental and serial urine data.