Strains of the ubiquitous xerophilic fungus Paecilomyces variotii can quantitatively convert the fungicide 2,4,6-tribromophenol to its musty-smelling metabolite, 2,4,6-tribromoanisole. Conversion was complete at the end of 6 weeks. A trained sensory panel found the odor threshold concentrations of 2,4,6-tribromoanisole to be 2 × 10-5 μg/L in water and 2 × 10-3 μg/kg in sultanas. Studies also showed that 2,4,6-tribromoanisole could produce a musty taint in sultanas packaged in polyethylene pouches after only 1 week of storage in the presence of fiberboard that contained 300 ng of this compound; the taint was produced at both 22 and 30 °C. An analytical method based on multiple-ion detection GC−MS was used for the measurement of 2,4,6-tribromoanisole in packaging materials and food. Keywords: 2,4,6-Tribromoanisole; 2,4,6-tribromophenol; fungal metabolite; musty odor; odor threshold; GC−MS analysis