Determinants, reproducibility, and seasonal variation of bacterial cell wall components and viable counts in house dust

• Published in: Indoor air Vol. 25; no. 3; pp. 260 - 272
• Main Authors: Leppänen, H. K., Täubel, M., Roponen, M., Vepsäläinen, A., Rantakokko, P., Pekkanen, J., Nevalainen, A., von Mutius, E., Hyvärinen, A.
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.06.2015; Hindawi Limited
• Subjects: 3-OH fatty acids; Actinobacteria - chemistry; Actinobacteria - isolation & purification; Actinomycetes; Air Pollution, Indoor - analysis; Bacteria - chemistry; Bacterial Load; Cell Wall - chemistry; Cell Wall - microbiology; Determinants; Dust; Dust - analysis; Environmental Exposure - analysis; Fatty Acids - analysis; Finland; Houses; Housing; Humans; Indoor air quality; Muramic acid; Muramic Acids - analysis; Reproducibility; Reproducibility of Results; Seasons; Viable bacteria; Viable bacteria; Muramic acid; Determinants; Actinomycetes; Reproducibility; 3-OH fatty acids
• ISSN: 0905-6947; 1600-0668
• DOI: 10.1111/ina.12141

The objectives of this study were (i) to assess the determinants that affect concentrations of the bacterial cell wall components 3‐hydroxy fatty acids (3‐OH FAs) and muramic acid and of total viable bacteria and actinomycetes in house dust; and (ii) to examine the seasonal variation and reproducibility of these bacterial cell wall components in house dust. A number of lifestyle and environmental factors, mostly not consistent for different bacterial measures but commonly including the type of dwelling and farming (number of livestock), explained up to 37% of the variation of the bacterial concentrations in 212 homes in Eastern Finland. The reproducibility of 3‐OH FAs and muramic acid measurements in house dust were studied in five urban homes and were found to be generally high (ICC 74–84%). Temporal variation observed in repeated sampling of the same home throughout a year was more pronounced for 3‐OH FAs determinations (ICC 22%) than for muramic acid (ICC 55–66%). We conclude that determinants vary largely for different types of bacterial measurements in house dust; the measured parameters represent different aspects of the bacterial content indoors. More than one sample is needed to describe bacterial concentrations in house dust in the home environment due to large temporal variation.