bacterial community of building dust in pacific northwest

The indoor microbial community is primarily sourced from indoor occupants and from outdoor microbial communities which are dispersed indoors from outdoor-sourced ventilation or occupant traffic. It is unknown whether the use of cross-laminated timber (CLT) building materials would directly contribute to the indoor microbial community, either by direct deposition of microorganisms from materials into general dust, or through the contribution of solid or gaseous chemicals which might affect microorganisms. Because the nascency of the construction of CLT buildings, there are not enough CLT buildings with comparable conventionally-constructed buildings to provide an objective analysis. Due to the unique combination of occupants, building materials, local environmental conditions, and geographic location, the microbial communities in buildings tend to be highly variable between different structures. Thus, we sought to answer within-building research questions: 1) does collection-height matter when collecting settled dust for assessing indoor bacterial communities, and 2) does cardinal direction in a building have any implications for the indoor microbial community with respect to the relative impacts of sunlight exposure and occupancy level?