Will Cities of the Future Embrace Bacteria?

Passengers wear surgical masks while commuting on the subway in Mexico City during flu season. (Photo: Eneas De Troya/flickr)

When I travel by subway, I often stand, holding onto one of the vertical poles. In those moments, I will myself not to think about all the bacteria that's probably marching determinedly from the pole to my hand. That's because, like you, I've heard countless stories about the various types of bad-for-you bacteria (from the stomach-upsetting variety to the flesh-eating kind) that are found on swabs taken in public toilets, people's never-cleaned phones — and subway poles.

Despite my paranoia, I understand the risks associated with antibacterial wipes and soaps, so I'm conscientious about washing my hands, which is a solid defense against the nasties. Nonetheless, there are some days I definitely want to blast the train car with bleach. But scientists in the relatively new field of urban microbiology are finding that like our guts, our cities benefit from the good bacteria that's hanging around. So wiping it all out — which many building materials, cleaning agents, and HVAC air filters do — may be doing more harm than good. Sure, we're getting rid of the bad guys that cause staph infections, but we're also constantly flushing the good guys out, too.

This type of bacteriology is a relatively new field, and there's much we don't know. Of the trillion or so bacteria, viruses and fungi, we've only identified about half of the species out there. So when scientists swab subway surfaces, they're finding plenty they just don't know much about — be them harmful or helpful. But the more researchers study, the more beneficial bacteria they find — so much so that the standard practice of sterilization may soon be replaced with protocols and materials that welcome or encourage bacteria for better health.

Humans and microbes might be better together

In this new scenario, our built environment (buildings, subway tunnels and homes) would be integrated into the local bacterial environment, not separated from it.

In fact, our current building systems, which isolate and filter air might soon be considered old fashioned — and unhealthy. While the science isn't definitive yet, there are ongoing studies looking at how more diverse local microbial ecosystems directly affect human health. We already know that children who grow up in a bacteria-rich environment, like a farm, have fewer asthma diagnoses and allergies than those who don't. So instead of antimicrobial building materials in homes and schools, we should be investigating building materials that encourage air cleaning — plants like moss and lichen, or specific types of bacteria. Instead of buildings that are sealed off from outside air, we could fill them with fresh outdoor air, complete with all its beneficial microbes, with the ultimate goal of making our indoor air mimic outdoor air, because it's rich with microbes.

In fact, the video below showcases the work of sustainable architect Vincent Callebaut, who envisions buildings doing so much more than merely being buildings. (Don't just stand there; suck up some CO2 while you're at it.)

'Nature got it right'

"There’s momentum around this idea that nature got it right," Kevin Van Den Wymelenberg told Fast Company. Van Den Wymelenberg is an associate professor at the University of Oregon in the Department of Architecture and director of the Energy Studies in Buildings Laboratory. "Until 100 years ago, we were living in buildings that were designed to be heating systems, cooling systems, fresh air systems, lighting systems — the buildings themselves were designed through their architecture to provide these human needs."

Think of windows in a Victorian home, which are meant to be open wide, and spacing that encourages natural cross-ventilation, cellars that keep the first floor naturally cool, or large overhangs that shelter us from summer sun and winter snows. "With the industrial revolution, development of the fluorescent light bulb, the reliable electric grid, mechanical cooling, everything changed," says Van Den Wymelenberg. We all got sealed inside buildings with recycled air, which may not be as good for us as fresh air, even if you're in a building with a good HVAC system. (And older or unmaintained HVAC systems can compromise indoor air quality significantly.)

The researchers — and forward-looking designers and architects who are working with them — see cities of the future as teeming with bacterial life, plants and fungus; the opposite of the sterile future others have imagined for our urban spaces. They're even designing materials like bricks that encourage the growth of small plants and moss, or more natural rock exteriors to create environments to encourage natural biodiversity. This would change how our cities look too, of course, getting us closer to those plant-covered buildings sci-fi artists have often created in imagining a utopian setting.

In reality, the way our urban environments look in the future may have more to do with supporting the tiniest of organisms and less to do with aesthetics, but either way, it will change the way our cities look and feel.