Toxicity of airborne dust as an indicator of moisture problems in school buildings.
Moisture-damaged indoor environments are thought to increase the toxicity of indoor air particulate matter (PM), indicating that a toxicological assay could be used as a method for recognizing buildings with indoor air problems. We aimed to test if our approach of analyzing the toxicity of actively collected indoor air PM in vitro differentiates moisture-damaged from non-damaged school buildings. We collected active air samples with NIOSH Bioaerosol Cyclone Samplers from moisture-damaged (index) and non-damaged (reference) school buildings (4 + 4). The teachers and pupils of the schools were administered a symptom questionnaire. Five samples of two size fractions [Stage 1 (>1.9 μm) and Stage 2 (1-1.9 μm)] were collected from each school. Mouse RAW264.7 macrophages were exposed to the collected PM for 24 h and subsequently analyzed for changes in cell metabolic activity, production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-6. The teachers working in the moisture-damaged schools reported respiratory symptoms such as cough (p = 0.01) and shortness of breath (p = 0.01) more often than teachers from reference schools. Toxicity of the PM sample as such did not differentiate index from reference building,s but the toxicity adjusted for the amount of the particles tended to be higher in moisture-damaged schools. Further development of the method will require identification of other confounding factors in addition to the necessity to adjust for differences in particle counts between samples.
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.
Jenni
J
Tirkkonen
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.|b Department of Health Protection, Living Environment and Health Unit , National Institute for Health and Welfare , Kuopio , Finland.
Martin
M
Täubel
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.|b Department of Health Protection, Living Environment and Health Unit , National Institute for Health and Welfare , Kuopio , Finland.
Hanna
H
Leppänen
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.|b Department of Health Protection, Living Environment and Health Unit , National Institute for Health and Welfare , Kuopio , Finland.
Matti
M
Peltonen
c Centers for Disease Control and Prevention , National Institute for Occupational Safety and Health , Morgantown , WA , USA.
William
W
Lindsley
c Centers for Disease Control and Prevention , National Institute for Occupational Safety and Health , Morgantown , WA , USA.
Bean T
BT
Chen
b Department of Health Protection, Living Environment and Health Unit , National Institute for Health and Welfare , Kuopio , Finland.
Anne
A
Hyvärinen
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.
Maija-Riitta
MR
Hirvonen
a Department of Environmental and Biological Sciences , University of Eastern Finland , Kuopio , Finland.
Kati
K
Huttunen
D016902:Air Pollution, Indoor / Q000009:adverse effects* / Q000032:analysis; D000818:Animals; D004391:Dust; D004784:Environmental Monitoring; D005260:Female; D006304:Health Status; D006801:Humans; D006813:Humidity; D015850:Interleukin-6 / Q000378:metabolism; D008297:Male; D051379:Mice; D009569:Nitric Oxide / Q000378:metabolism; D052638:Particulate Matter / Q000009:adverse effects* / Q000032:analysis; D000067996:RAW 264.7 Cells; D000070777:School Teachers; D012574:Schools; D013334:Students; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D004391:Dust; D015850:Interleukin-6; D052638:Particulate Matter; D014409:Tumor Necrosis Factor-alpha; C577686:interleukin-6, mouse; D009569:Nitric Oxide
Indoor air; PM; in vitro; moisture damage; school; toxicity