Stachybotrys mycotoxins: from culture extracts to dust samples

Area of Science:

• Environmental Science
• Mycology
• Analytical Chemistry

Background:

• Stachybotrys chartarum is a filamentous fungus known for producing toxic metabolites.
• Exposure to these mycotoxins is linked to health problems, including mycotoxicosis, in building occupants.

Purpose of the Study:

• Develop and validate an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method.
• Identify and quantify Stachybotrys metabolites in fungal cultures, wall scrapings, and settled dust.
• Investigate the presence and distribution of mycotoxins in a water-damaged building.

Main Methods:

• Ultra-high performance liquid chromatography-quadrupole time-of-flight (UHPLC-QTOF) screening.
• Development of a UHPLC-MS/MS method for metabolite identification and quantification.
• Analysis of fungal culture extracts, wall scrapings, and settled dust samples.

Main Results:

• The UHPLC-MS/MS method identified 12 Stachybotrys metabolites.
• Four metabolites were quantified, and six were estimated based on standards.
• Coexistence of S and A chemotypes of S. chartarum was observed.
• Macrocyclic trichothecenes (roridin E) and multiple spirocyclic drimanes were detected in settled dust.
• Spirocyclic drimanes were found in all analyzed dust samples, with higher concentrations in the water-damaged room.

Conclusions:

• The developed UHPLC-MS/MS method is effective for detecting Stachybotrys metabolites.
• Spirocyclic drimanes are widely distributed in dust and show potential as exposure biomarkers.
• This study links mycotoxin concentrations on surfaces to those found in settled dust.