Richard L. Corsi1, Hal Levin2, Jonathan Eisen3, and Kerry A. Kinney1

1. The University of Texas at Austin

2. microBEnet and Building Ecology Research Group

3. microBEnet - University of California, Davis

Microbiomes of Built Environments: 2011 Symposium Highlights & Workgroup Recommendations

Healthy Buildings 2012 - Brisbane, Australia

Indoor Air 2011: Symposium on June 8th / 9th, 2011 (Austin, Texas)– 9,

Symposium Overview

DAY 1

• Keynote: J. Craig Venter

• 15 podium speakers

Day 2

• State of Knowledge: Aino Nevalainen

• New Tools and Opportunities: Jonathan Eisen

• Need to think big: Jesse Ausubel

• Workshop

Sponsored by the Alfred P. Sloan Foundation

Workgroup Recommendations

1. Microorganisms & Building Materials

• Far more attention needed - interaction with materials

• Material properties (composition, porosity, water capacity)

• Surface temperature and humidity

• Microbial communities on damp materials

• Fungi, bacteria (100% of materials)

• Amoebae (20% of materials)

• Aged wood, gyp board, mineral wool

• Synergistic effects?

• Yli-Pirilä et al. (2004 & 2008)

2. Longitudinal Studies in Buildings

• How do microbial communities change over time and why?

• Changes (or controlled perturbations) in:

• Outdoor environmental conditions

• Indoor environmental conditions

• Building materials/furnishings

• Operations (HVAC, etc.)

• Maintenance (cleaning, etc.)

• Occupant loads / activities

U of Chicago – Center for Health Statistics http://healthstats.org/

3. Reference Genomes of Cultured Isolates

• Sequencing of “reference genomes” from cultured isolates

• Different types of microorganisms removed from buildings

• Valuable community resource

• Predicting functions of importance

• Interpretation of PCR and metagenomic

sequence data

4. Functioning of Microorganisms

• Cataloging is good, but not sufficient in and of itself

• Need to know what the microorganisms are doing

“You can observe a lot just by watching.” – Yogi Berra

5. Shared Buildings

• Several around the world are needed (different climate zones)

• Many benefits:

• Controlled and systematic research efforts

• International & interdisciplinary collaborations

• Compare sampling methods between teams

• Deeper exploration: environmental, building, occupant factors

• Facilitate proposal development

6. Human Occupants

• Humans are important sources of bacteria (Täubel et al., 2009)

• Mattresses: 69-88% of bacteria of human origin

• Floor dust: 45-55% of bacteria of human origin

• Spatial activity patterns & resuspension (e.g., Hospodsky et al., 2012)

• Research needed on behavior & activity effects

• Cleaning practices (how and how frequently, etc.)

• Surface cleaning, vacuum cleaning, etc.

• Microbial community variations / redistribution

• Occupant profiles

• Age, gender, culture, socioeconomics

• Psychology/personality

7. Non-Human Occupants

• Pets can be important sources of bacteria

• Canine contributions (Johansson et al., 2011)

• 2+ dogs: Strong predictor of streptomycetes & endotoxins

• Variations: outdoor/indoor pets versus indoor pets?

• Diet effects?

• Age effects?

• Cleaning effects?

Chloe Corsi outdoor/indoor Australian cattle dog

8. Effects of Climate Change

• How do indoor microbiomes change as climate changes?

• Direct impacts of climate change

• Heat waves, dust storms

• more intense rainfall, etc.

• Mitigation and adaptation effects on buildings

• Weatherization / tight envelope design

• Rapid implementation of green building materials

• New insulations, etc.

Griffith, Australia 2002

9. Metadata Consensus

• Standardized checklist(s) for researchers

• Sampling methodologies

• Environmental conditions

(what, when, where)

• Building design and layout

• Building ventilation methods

• HVAC system / components

• Building materials

• Building operation parameters

• Building maintenance (cleaning, etc.)

• Previous water challenges

• Flexibility – One size does not fit all!

50 oC

23 oC

13 oC

35 oC

18 oC18-32 oC

10

15

20

25

30

35

40

Tem

pe

ratu

re (

oC

)Difference between supply & attic ≈ 0 - 20 oC (68 oF)

Maximum difference can exceed 40 oC (104 oF)

Attic

IndoorOutdoor

Supply Vent

10. Microbial Communities and Chemicals

• Changes in surface chemistry via pH changes

• CO2, NOx, cleaners (HOCl, etc.)

• Chemicals deposited on surfaces

• Chemical transformations of surfaces

11. Citizen (building/microbial) Science

• Get general population excited and involved

• Sample collection in homes, schools, etc.

• Possibility of HVAC filters as integrated samplers

• Centralized analysis sites for “citizen samples”

• Metadata via questionnaire

12. Routine Surveillance Technologies

• Development & verification of new technologies

• Routine surveillance of indoor microorganisms

• If low cost – facilitate citizen science

Grand Challenge

1. How do we improve characterization/testing of existing and

new building materials & their influence on microbes

• Key properties & changes with time?

• Test protocols?

• Microbial communities?

2. How do we effectively build spatial and temporal variability

into field studies?

• Microbial sampling

• Building and environmental condition sampling

Design, operate, & maintain microbially-balanced, healthy buildings