Report on Day 2 of the “Microbiomes of the Built Environment: From Research to Application”. My report and Storify of tweets from Day 1 can be found here.
Session #1 “Beyond Bacteria: Viral and Fungal Ecology in Indoor Environments”
First speaker was Linsey Marr “Viruses in the Built Environment”. Talking about their work looking at seasonality of viruses in daycare centers, detailed studies of Influenza A, and others. Interesting finding that viruses were more concentrated outdoors than indoors, and that similar numbers of bacteria and viruses were found. Described a vertical concentration gradient of particles, but only a 15% difference in exposure between 1 meter and 2 meters from floor. Described how airborne viruses are subject to aerosol dynamics.
Next was John Taylor “Fungi in the Built Environment”. Started off talking about the Rachel Adams study in student housing at Berkeley where they found that dispersal and geography/season were the primary drivers of fungal populations (not occupant behavior). Found the reverse for bacteria (affected by occupants). Showing data that shedding is less important than resuspension of environmental microbes. Several studies showing that indoor air looks a lot like outdoor air, with some extra bacteria from people. Talked about practical implications of this work, for example with litigation around poorly maintained buildings.
Session #2 “Built Environment Interventions and the Microbiome: Impacts and Tradeoffs”
Mark Mendell went next with “Changing Indoor Microbial Environments to Benefit Human Health: What Do We Know?”. Started off by saying how much more complicated we have made our knowledge about microbes in the built environment. Basically reviewed the entire literature on health effects. He talked about which microbial/environmental factors are correlated with positive or negative health outcomes. Too hard to summarize here! See the Storify below for more details, I’m going to try to get his slides to post here.
Then Michael Waring “Bio-walls and Indoor Houseplants: Facts and Fictions”. He talked about the various claims being made in the world about the cleansing effects of plants. He then went back to the famous NASA study (that we’ve blogged about in the past) and went through the literature and basically concluded that to have any effect at all you would need more plants per square meter than could possibly fit in the space. At a high air exchange rate you would need 500 potted plants per square meter! Then he talked about bio-walls, which he showed could theoretically actually clean air. However, there are a number of disadvantages of biowalls in terms of emitting other VOCs, humidity concerns, and cost. His conclusion was that for air cleaning, we’d be better off with just increased ventilation.
Session #3 “Perspectives from Building Design and Commissioning”
Started with Kevin van den Wymelenberg “What the Design Community Needs to Incorporate Consideration of the Microbiomes of the Built Environment Into the Design of Facilities”. Kevin is an architect and he presented that perspective to the audience. Talked about the possible tradeoff between energy and health and the need to harness the creativity of architects. In a similar vein he talked about the need to excite people about our results and the importance of engaging architects, engineers, and industry.
Last talk (remote) of the meeting was Robin Guenther. My computer died *and* her talk title wasn’t in the program so I don’t know the title. But basically she posed 4 key questions, from a healthcare architect perspective, that she thinks should be answered. She made the point that architects make choices that influence health, but don’t always think of it that way. She discussed the move to “tight” buildings and wondered what effect that will have on the microbiome. Informed us that hospitals are driving much of the product development in antimicrobial materials.