Grantee Research Project Results
2017 Progress Report: Impacts of Weatherization on Microbial Ecology and Human Health
EPA Grant Number: R835757Title: Impacts of Weatherization on Microbial Ecology and Human Health
Investigators: Brown, G Z , Den Wymelemberg, Kevin Van , Johnson-Shelton, Deborah , Green, Jessica
Current Investigators: Brown, G Z , Johnson-Shelton, Deborah , Green, Jessica , Den Wymelemberg, Kevin Van
Institution: University of Oregon , Oregon Research Institute
EPA Project Officer: Chung, Serena
Project Period: August 1, 2015 through April 30, 2017 (Extended to April 30, 2018)
Project Period Covered by this Report: August 1, 2016 through July 31,2017
Project Amount: $993,557
RFA: Indoor Air and Climate Change (2014) RFA Text | Recipients Lists
Research Category: Air Quality and Air Toxics , Climate Change , Air
Objective:
This study is investigating weatherization in single-family detached homes in two Oregon climate zones during the winter and summer seasons. Data in this study is being assembled from microbial sampling, air quality measurements, architectural inventories and performance tests, and household member health and behavior surveys. The overarching goal in this project is to quantify the relationships between ventilation strategies, indoor air quality, and microbial ecology in weatherized residential homes and their effects on human health. The study also seeks to determine ventilation configurations in which the building envelope-supplied source can be used with designed natural ventilation to reduce energy use in the majority of U.S. climates. Finally, the project intends to provide better understanding of the role of occupant behavior in building operation resulting from weatherization programs and how this affects occupant health. Our study addresses four questions: 1) what role does the building envelope play in attenuating or distributing the outdoor microbiota indoors under ASHRAE 62.2-2013 post-weatherization whole house residential ventilation systems?; 2) how does the ventilation source, either duct or building envelope, influence the similarity of the indoor microbiome to the outdoor microbiome?; 3) is there a seasonal or climate influence affecting the structure of indoor microbiota?; and 4) Does occupant behavior after weatherization affect indoor air contaminants and health? The resulting data will provide an empirical basis to inform the design of healthier buildings.
Summary/Accomplishments (Outputs/Outcomes):
Two additional weatherization partners were brought onto the project to supplement recruitment efforts; both of these serve low-income clients. Field collection was completed, for a total of 179 home visits to collect a week of inside and outside time-resolved air quality and environmental data and time-integrated microbial samples. These visits occurred before and after weatherization for paired treatment (weatherization) and comparison (not weatherized) homes in 2 climate zones in Oregon. Furthermore, a 61-item occupant survey on health and home operation behavior was administered during each collection period; these surveys represent 167 individuals living in the homes. The site collected time-resolved data is undergoing curation and preliminary analysis. DNA from the first cohort of microbial samples was extracted and sequenced for characterization of bacterial and fungal communities. An inventory of architectural characteristics and infiltration performance of each home was collected during the home visits and from the weatherization partners and their contractors.
The REDCap online survey and database system was used to track all aspects of recruitment, consenting, home visits scheduling, survey distribution, incentive payments, and hazard notifications. REDCap (https://projectredcap.org/) is a secure, HIPAA-compliant, web-based application designed to support data capture for research studies.
Conclusions:
In the coming year a final survey will be distributed to homeowners at roughly one year after the initial survey to explore changes to health and behavior after weatherization. The second cohort of microbial samples will be sequenced. Curation of the air quality, environmental, and inventory datasets will be completed. Data analysis will be completed, utilizing multivariate analysis techniques designed for ecological inference of microbial communities and to describe how environmental variables influence air quality. We will use nonmetric multi-dimensional scaling and constrained ordination techniques will be used to explore the most relevant environmental factors associated with microbial community composition and community dynamics, and discriminant analysis to test the relative importance of environmental parameters on microbial community variation. Comparisons of indoor vs. outdoor measurements will provide a description of how the building envelope and ventilation systems mediate indoor conditions. We will also analyze our samples in the context of potential source environments, and across multiple publicly-available indoor microbial datasets to better understand the generality of the patterns we observe. Pre-post household survey responses will be studied using a combination of descriptive analyses, regression techniques, and mixed model analysis to compare occupant demographics, occupant-reported physiological and mental health and building operations and attitudes before and after the weatherization. We will also use weighted regression analysis to consider cluster effects of households nested within the study’s two geographic regions.
We will be writing several papers during the coming year. One of these will be an integrated analysis of the various datasets, while several other papers will be published that are more discipline-specific. We will continue to attend conferences; to-date we have been invited or accepted to the following: the 2017 AIA Design and Health Research Consortium Convening Meeting, the 2017 Society of Prevention Research Annual Meeting, the 2017 Sloan Microbiology of the Built Environment Conference, the 2017 Harvard Healthcare Symposium, the Health + Energy Research Consortium 2017, and the Mycological Society of America Annual Meeting 2017.
Progress Summary:
Two additional weatherization partners were brought onto the project to supplement recruitment efforts; both of these serve low-income clients. Field collection was completed, for a total of 179 home visits to collect a week of inside and outside time-resolved air quality and environmental data and time-integrated microbial samples. These visits occurred before and after weatherization for paired treatment (weatherization) and comparison (not weatherized) homes in 2 climate zones in Oregon. Furthermore, a 61-item occupant survey on health and home operation behavior was administered during each collection period; these surveys represent 167 individuals living in the homes. The site collected time-resolved data is undergoing curation and preliminary analysis. DNA from the first cohort of microbial samples was extracted and sequenced for characterization of bacterial and fungal communities. An inventory of architectural characteristics and infiltration performance of each home was collected during the home visits and from the weatherization partners and their contractors.
The REDCap online survey and database system was used to track all aspects of recruitment, consenting, home visits scheduling, survey distribution, incentive payments, and hazard notifications. REDCap (https://projectredcap.org/) is a secure, HIPAA-compliant, web-based application designed to support data capture for research studies.
Future Activities:
In the coming year a final survey will be distributed to homeowners at roughly one year after the initial survey to explore changes to health and behavior after weatherization. The second cohort of microbial samples will be sequenced. Curation of the air quality, environmental, and inventory datasets will be completed. Data analysis will be completed, utilizing multivariate analysis techniques designed for ecological inference of microbial communities and to describe how environmental variables influence air quality. We will use nonmetric multi-dimensional scaling and constrained ordination techniques will be used to explore the most relevant environmental factors associated with microbial community composition and community dynamics, and discriminant analysis to test the relative importance of environmental parameters on microbial community variation. Comparisons of indoor vs. outdoor measurements will provide a description of how the building envelope and ventilation systems mediate indoor conditions. We will also analyze our samples in the context of potential source environments, and across multiple publicly-available indoor microbial datasets to better understand the generality of the patterns we observe. Pre-post household survey responses will be studied using a combination of descriptive analyses, regression techniques, and mixed model analysis to compare occupant demographics, occupant-reported physiological and mental health and building operations and attitudes before and after the weatherization. We will also use weighted regression analysis to consider cluster effects of households nested within the study’s two geographic regions.
We will be writing several papers during the coming year. One of these will be an integrated analysis of the various datasets, while several other papers will be published that are more discipline-specific. We will continue to attend conferences; to-date we have been invited or accepted to the following: the 2017 AIA Design and Health Research Consortium Convening Meeting, the 2017 Society of Prevention Research Annual Meeting, the 2017 Sloan Microbiology of the Built Environment Conference, the 2017 Harvard Healthcare Symposium, the Health + Energy Research Consortium 2017, and the Mycological Society of America Annual Meeting 2017.
Journal Articles:
No journal articles submitted with this report: View all 17 publications for this projectSupplemental Keywords:
weatherization, microbial ecology, air quality, health, behaviorRelevant Websites:
• The project recruitment website, Weatherization and Air Quality Study Exit Exit
• Weatherization partner recruitment website, Enhabit Exit Exit
Progress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.