Ecologist Jessica Green thinks of indoor air as a microbial
garden, and she thinks architects and biologists can collaborate to make our
indoor environments much healthier for humans.
In a TEDx talk, Green describes what we are doing
to indoor air now. She calls it "microbial genocide.” We seal the buildings
and use air conditioning and filtration systems to make sure outdoor microbes
don’t get in. People come in
bringing millions of microbes shedding from their bodies and they stir up the
microbial dust languishing every surface.
We keep the temperature and humidity in the same narrow range. And then, she says, we regularly kill
every organism we can with antimicrobial cleaning products. "If you had a garden,” she says, "you’d
never kill everything in it to get rid
of one weed.”
Microbes—bacteria, viruses and archaea—are the most abundant
organisms on earth, and while some make us sick, our bodies need many of them
to protect us from pathogens, and boost our immune systems. They even influence our moods. "When you clean the organisms from an
ecosystem,” she explains, "you make space for the weedy and fast growing organisms to come in and colonize those
Green is an associate professor at
the University of Oregon, and a
co-founder of the university’s Biology and Built Environment Center.
She began her career researching microbes in the Arctic and other exotic
places. She also had background in civil and environmental engineering and she
realized examining the built environment where we spend 90 percent of our time
would make her research relevant to issues surrounding sustainability, design
and human health. A Discover Magazine story by Bruce Barcott reports that G.Z.
"Charlie” Brown, a colleague at the University of Oregon
and an expert in sustainable buildings, wanted research data to influence a new
generation of hospitals on how energy-saving ventilation systems could also
produce healthier hospital air. Green persuaded the Alfred P. Sloan Foundation
to put up the money and the BioBE Center was born.
The Discover story
describes Green as an adventurous scientist and a fearless athlete. She was known as Thumper Biscuit in her
Roller Derby competition days. A Forbes magazine
story by Bruce
Upbin explains she and her colleagues have worked with architectural modeling software,
genetic sequencing, and microbial
ecology to map the microbiomes of
the built environment. "We’ve
learned that architects are impacting what microbes live where,” she told Forbes. "It’s a new dimension of
their work.” Surfaces of desks,
for example, foster microbial colonies that differ from the colonies living on
walls near air conditioning vents.
In research relevant to hospitals, Green and colleagues
compared microbial environments in rooms with open windows and sealed rooms
with mechanical ventilation systems. In a TED talk, she says green
buildings, designed to let outside air in, fostered a
diverse microbial mix that included organisms one finds outdoors in plants and
soil, and a higher likelihood of organisms that promote health. In rooms with
mechanically ventilated air, the microbial populations were less diverse, and
more akin to the populations associated with humans, and had a higher
probability of carrying pathogens.
populations, as in agriculture, monocultures tend to be unhealthy. People eat probiotic yogurt for health, and the same principle may apply
to interior spaces. The Forbes story says Ford has contacted Green about
design to foster health-promotion organisms inside its cars and trucks.
"There are organisms that make our skin more supple and smooth,” Green told
Forbes. "I can totally see it: the probiotic steering wheel.”
Humans have been around for hundreds of thousands of years,
but only in the last 60 years or so have we spent most of our time in
hermetically sealed indoor environments, Green observes. She among the scientists pioneering the research
to learn what that means. One
possibility she speculates, is that "We
are growing a microbial monoculture, and our bodies probably have not
evolved to function well in this microbial environment.” Some evidence suggests
indoor living may be associated with antibiotic resistance and auto immune
disorders such as asthma and allergies.
Research by Green and others may lead to new floor plans, new ventilation systems, and new ways to grow
robust, diverse and healthy microbial gardens inside our buildings. Green
coauthored the paper Architectural Design Influences the Diversity and
Structure of the Built Environment Microbiome.