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We examined growth of mixed microbial cultures (13 fungal species and one actinomycete species) and production of volatile compounds (VOCs) in typical building materials in outside walls, separating walls, and bathroom floors at various relative humidities (RHs) of air. Air samples from incubation chambers were adsorbed on Tenax TA and dinitrophenylhydrazine cartridges and were analyzed by thermal desorption-gas chromatography and high-performance liquid chromatography, respectively. Metabolic activity was measured by determining CO2 production, and microbial concentrations were determined by a dilution plate method. At 80 to 82% RH, CO2 production did not indicate that microbial activity occurred, and only 10% of the spores germinated, while slight increases in the concentrations of some VOCs were detected. All of the parameters showed that microbial activity occurred at 90 to 99% RH. The microbiological analyses revealed weak microbial growth even under drying conditions (32 to 33% RH). The main VOCs produced on the building materials studied were 3-methyl-1-butanol, 1-pentanol, 1-hexanol, and 1-octen-3-ol. In some cases fungal growth decreased aldehyde emissions. We found that various VOCs accompany microbial activity but that no single VOC is a reliable indicator of biocontamination in building materials.

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Organophosphorus compounds (OPs) and tetrabromobisphenol A (TBBPA) are widely utilized as flame retardants (FRs) in plastics, textiles, rubbers, and building materials. Eight OPs and TBBPA were quantified by GC/MS from air samples collected from a furniture workshop, a circuit board factory, two electronics dismantling facilities, a computer classroom, and offices and social premises. In addition, dermal exposure was assessed with patch and hand wash samples at some workplaces. Triphenyl phosphate, tris(2-chloroethyl) phosphate, and tris(2-chloroisopropyl) phosphate were typical contaminants of the workplaces, whereas TBBPA, tricresyl phosphate, tri-n-butyl phosphate, and tris(2-ethylhexyl) phosphate were rather site-specific. The highest geometric mean of total FRs in the air samples was measured in personal samples atthe electronics dismantling facilities (2.9 and 3.8 microg/m3), whereas the stationary sample results from the other environments ranged between 90 and 720 ng/m3. Stationary samplings underestimated the personal exposure at three out of four work places where comparisons were made. Dermal exposure was shown for the first time at these occupational settings. The geometric mean of totalFR levels in patch samples ranged between 1.5 and 24 ng/cm2 and in hand wash samples between 3.5 and 34 microg/ two hands. The health effects of the measured FR levels remain unknown.

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