Investigation of Mold Growth in Indoor School Buildings by Monitoring Outgassed Methyl Benzoate as a MVOC Biomarker

Abstract

An investigation of 16 classrooms in 4 randomly selected schools (children age 6—12) and 7 different places at the University of Waterloo, Waterloo, ON, Canada and 4 locations at Sir Wilfred Grenfell College, MUN, Corner Brook, NL, Canada were conducted to quantify emitted methyl benzoate concentrations. Methyl benzoate — as a metabolic biomarker of mold growth — has potential as an indicator for other volatile organic compound emissions outgassed by bacteria and molds. A variety of solid and indoor air grab samples were taken from the selected locations and were immediately analyzed by solid phase microextraction and gas chromatography/mass spectrometry. By this rapid method, methyl benzoate concentrations in solid samples were found to range: 5—69 and 6—22 ppb for schoolrooms and university rooms, respectively. For air samples, methyl benzoate (quantitation limit 2 ppb) was not detected in the schools, however at the universities; concentrations were as high as 25 ppb. This study supports that methyl benzoate may have use, as an indicator of mold growth, in indoor air research.