Title: | Non-microbial sources of microbial volatile organic compounds |
Author(s): | Choi H; Schmidbauer N; Bornehag CG; |
Address: | "Department of Environmental Health Sciences, University at Albany, School of Public Health, State University of New York, United States. Electronic address: hchoi@albany.edu. Norwegian Institute for Air Research, PO Box 100, 2027 Kjeller, Norway, Instituttveien 18, 2007 Kjeller, Norway. Electronic address: ns@nilu.no. Technical Research Institute of Sweden, Box 857, SE-501 15 Boras, Sweden; Department of Public Health Sciences, Karlstad University, SE-651 88 Karlstad, Sweden. Electronic address: Carl-Gustaf.Bornehag@kau.se" |
DOI: | 10.1016/j.envres.2016.03.026 |
ISSN/ISBN: | 1096-0953 (Electronic) 0013-9351 (Linking) |
Abstract: | "BACKGROUND: The question regarding the true sources of the purported microbial volatile organic compounds (MVOCs) remains unanswered. OBJECTIVE: To identify microbial, as well as non-microbial sources of 28 compounds, which are commonly accepted as microbial VOCs (i.e. primary outcome of interest is Sigma 28 VOCs). METHODS: In a cross-sectional investigation of 390 homes, six building inspectors assessed water/mold damage, took air and dust samples, and measured environmental conditions (i.e., absolute humidity (AH, g/m(3)), temperature ( degrees C), ventilation rate (ACH)). The air sample was analyzed for volatile organic compounds (mug/m(3)) and; dust samples were analyzed for total viable fungal concentration (CFU/g) and six phthalates (mg/g dust). Four benchmark variables of the underlying sources were defined as highest quartile categories of: 1) the total concentration of 17 propylene glycol and propylene glycol ethers (Sigma17 PGEs) in the air sample; 2) 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate (TMPD-MIB) in the air sample; 3) semi-quantitative mold index; and 4) total fungal load (CFU/g). RESULTS: Within severely damp homes, co-occurrence of the highest quartile concentration of either Sigma17 PGEs or TMPD-MIB were respectively associated with a significantly higher median concentration of Sigma 28 VOCs (8.05 and 13.38mug/m(3), respectively) compared to the reference homes (4.30 and 4.86mug/m(3), respectively, both Ps =0.002). Furthermore, the homes within the highest quartile range for Sigma fungal load as well as AH were associated with a significantly increased median Sigma 28 VOCs compared to the reference group (8.74 vs. 4.32mug/m(3), P=0.001). Within the final model of multiple indoor sources on Sigma 28 VOCs, one natural log-unit increase in summed concentration of Sigma17 PGEs, plus TMPD-MIB (Sigma 17 PGEs + TMPD-MIB) was associated with 1.8-times (95% CI, 1.3-2.5), greater likelihood of having a highest quartile of Sigma 28 VOCs, after adjusting for absolute humidity, history of repainting at least one room, ventilation rate, and mold index (P-value =0.001). Homes deemed severely mold damaged (i.e., mold index =1) were associated with 1.7-times (95% CI, 0.8-3.6), greater likelihood of having a highest quartile of Sigma 28 VOCs, even though such likelihood was not significant (P-value =0.164). In addition, absolute humidity appeared to positively interact with mold index to significantly elevate the prevalence of the highest quartile category of Sigma 28 VOCs. CONCLUSION: The indoor concentration of Sigma 28 VOCs, which are widely accepted as MVOCs, are significantly associated with the markers of synthetic (i.e. Sigma17 PGEs and TMPD-MIB), and to less extent, microbial (i.e., mold index) sources" |
Keywords: | "Air Microbiology Air Pollutants/*analysis Air Pollution, Indoor/*analysis Dust/analysis Environmental Monitoring Fungi/*isolation & purification Housing Humidity Phthalic Acids/analysis Temperature Ventilation Volatile Organic Compounds/*analysis Allergie;" |
Notes: | "MedlineChoi, Hyunok Schmidbauer, Norbert Bornehag, Carl-Gustaf eng Research Support, Non-U.S. Gov't Netherlands 2016/04/05 Environ Res. 2016 Jul; 148:127-136. doi: 10.1016/j.envres.2016.03.026. Epub 2016 Apr 1" |