Indoor air particles and bioaerosols before and after renovation of moisture-damaged buildings: the effect on biological activity and microbial flora.
Many building-related health problems coincide with moisture damage and mold growth within a building. Their elimination is assumed to improve indoor air quality. The aim of this study was to follow the success of remediation in two individual buildings by analyzing the microbial flora and immunotoxicological activity of filter samples. We compare results from samples collected from indoor air in the moisture-damaged buildings before and after renovation and results from matched reference buildings and outdoor air. The microbial characteristics of the samples were studied by analyzing ergosterol content and determining the composition of fungal flora with quantitative polymerase chain reaction (QPCR). In addition, the concentrations of particles were monitored with optical particle counter (OPC). The immunotoxicological activity of collected particle samples was tested by exposing mouse macrophages (RAW264.7) for 24 h to particle suspension extracted from the filters, and measuring the viability of the exposed cells (MTT-test) and production of inflammatory mediators (nitric oxide, IL-6 and TNF*) in cell culture medium by enzyme-linked immunoassay (ELISA). The results show that for Location 1 the renovation decreased the immunotoxicological activity of the particles collected from damaged building, whereas no difference was detected in the corresponding samples collected from the reference building. Interestingly, only slight differences were seen in the concentration of fungi. In the Location 2, a decrease was seen in the concentration of fungi after the renovation, whereas no effect on the immunotoxicological responses was detected. In this case, the immunotoxicological responses to the indoor air samples were almost identical to those caused by the samples from outdoor air. This indicates that the effects of remediation on the indoor air quality may not necessarily be readily measurable either with microbial or toxicological parameters. This may be associated with different spectrum of harmful agents in different mold and moisture-damaged buildings.
Huttunen
Kati
K
Department of Environmental Health, National Public Health Institute, P.O. Box 95, FI-70701 Kuopio, Finland. Kati.Huttunen@ktl.fi
Rintala
Helena
H
Hirvonen
Maija-Riitta
MR
Vepsäläinen
Asko
A
Hyvärinen
Anne
A
Meklin
Teija
T
Toivola
Mika
M
Nevalainen
Aino
A
D000336:Aerosols; D000391:Air Microbiology / Q000592:standards*; D016902:Air Pollution, Indoor / Q000009:adverse effects / Q000032:analysis*; D000818:Animals; D002028:Building Codes; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003252:Construction Materials / Q000382:microbiology*; D004784:Environmental Monitoring; D004875:Ergosterol / Q000032:analysis; D005160:Facility Design and Construction / Q000379:methods / Q000592:standards; D005658:Fungi / Q000254:growth & development / Q000302:isolation & purification; D015850:Interleukin-6 / Q000032:analysis; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D009569:Nitric Oxide / Q000032:analysis; D052638:Particulate Matter / Q000032:analysis* / Q000633:toxicity; D013306:Streptomycetaceae / Q000254:growth & development / Q000302:isolation & purification; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis
D000336:Aerosols; D015850:Interleukin-6; D052638:Particulate Matter; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D004875:Ergosterol