Using the Microbiology and Chemistry of the Built Environment to Promote Indoor Environmental Quality

The built indoor environment is enriched for antibiotic-resistant pathogens compared to natural outdoor environments. In our quest to diminish the number of viable antibiotic-resistant pathogens indoors, with the ultimate goal of halting the spread of infectious disease, we have created an arsenal of synthetic antimicrobial chemicals such as triclosan, which we now embed in various products, from baby toys to building materials. Regardless of where we put these chemicals, they can have unintended consequences on indoor microbes by changing the structure of indoor microbial communities or selecting for certain functions, including antibiotic resistance.

Using molecular and traditional microbiology techniques, my research assesses whether antimicrobial chemicals are indeed associated with decreased microbial viability. We further evaluate whether antimicrobial chemical concentrations correlate with antibiotic resistance genes in the dust microbiome and phenotypes in cultivable isolates. Using synthetic microbial communities and microcosm experiments, we probe causal relationships between exposure to antimicrobial chemicals and the development of different resistance phenotypes and genotypes. Based on these findings, we are assessing new, bio-inspired approaches to controlling microbial communities. Together, this work provides a window into microbe-chemical interactions transpiring within buildings, giving us the knowledge we need to make better design choices.

Dr. Erica Marie Hartmann is an environmental microbiologist interested in the interaction between human-made chemicals and microbes. Her research career began at the Johns Hopkins Bloomberg School of Public Health, where she worked as on mass spectrometry-based methods for detecting microbial enzymes necessary for bioremediation. From Hopkins, she moved to Arizona State University where she was the first graduate of the interdisciplinary Biological Design PhD program. As part of her research there, she worked with environmental engineers to develop molecular methods to detect microbes in food, soil, and water samples. Following her graduation, she was awarded a Fulbright to study microbes that degrade the toxic, carcinogenic pollutants known as dioxins in France at the Commission for Atomic Energy. She then began leading studies on the effects of antimicrobial chemicals on the microbes found in indoor dust at the Biology and the Built Environment Center at the University of Oregon. Since joining Northwestern University in the Department of Civil and Environmental Engineering, she has continued her indoor microbiome work, as well as pursuing a variety of research questions related to microbe-chemical interactions.