Microbial counts and particulate matter levels in indoor air samples collected from a child home-care center in Bangkok, Thailand

To assess the microbial count (bacteria and fungi) and particulate matter with sizes less than 10 microm (PM10) level in indoor air of a child home-care center in Bangkok. A total of 287 air samples were collected from the indoor air of twenty households which were part of a child home-care center to assess bacterial and fungal counts (212 samples) and PM10 levels (66 samples). Additionally, fifty-two and twenty-six outdoor air samples were collected to compare microbial count and PMo10 levels. It was found that means + standard deviation (SD) for bacterial and fungal counts in the child home-care center were 527.8 +/- 230.9 cfu/m3 and 514.6 +/- 256.7 cfu/m3, respectively (those in outdoor air samples were 264.6 +/- 179.7 cfu/m3 and 308.7 +/- 217.3 cfu/m3, respectively). The mean +/- SD of PM10, level was 125.1 + 48.0 pg/m3 (that in outdoor air samples was 120.1 +/- 66.9 microg/m3). When compared with the levelfor the indoor air quality guideline, 47.2% and 47.6% of total air samples had bacterial and fungal counts higher than the recommended levels and 47.0% of total air samples had PM10 levels higher than the recommended level. The present study found that about 47% of total air samples collected from the child home-care center had bacterial and fungal counts and PM10 levels higher than the recommended levels. These results may affect the health of a child who spends most of his/her time in this center Some intervention or preventive endeavors should be undertaken, including periodic cleaning and maintenance of the ventilation systems and adoption of a regular schedule for room cleaning should be implemented.