Healthier cities are key to a healthier planet and healthier people

“We're in the middle of the sixth mass extinction of life on Earth, where we are literally driving life off the planet,” said Sam Myers, environmental health professor at the Johns Hopkins Bloomberg School of Public Health and founding director of the Johns Hopkins Institute for Planetary Health and the Planetary Health Alliance. “We’ve lost two-thirds of the population sizes of birds, reptiles, mammals, amphibians, and fish since 1950. So, there's been this unbelievably dramatic ballooning.”

Myer’s dire warning is a call for action for attendees of the inaugural Planetary Health Cities Symposium. Held June 16 at the Johns Hopkins University Bloomberg Center in Washington, D.C., the symposium explored solutions for improving cities and their impact on the planetary environment and human health and the health of the environment. According to the United Nations, more than 55 percent of the world’s population currently lives in cities or urbanized areas. That number is projected to grow to 70 percent by 2050.

Finding solutions for the built environment

The field of planetary health looks at human impact on nature’s interconnected systems. The field goes beyond climate change science and the mitigation of greenhouse gases to include how everyday activities impact biodiversity loss, deforestation, and environmental pollution, which in turn directly impacts human health.

The real estate industry could play a key role in reducing the environmental impact of our built environment, from the design of cities to the materials used to make and furnish homes, offices, and other buildings.

“Our goal is to develop a cross-disciplinary community and a set of principles for design, planetary health, friendly buildings, communities, and infrastructure,” explained Seydina Fall, director of the Master of Science in Real Estate and Infrastructure program at Carey Business School. “Ultimately, it is our hope that these principles will be adopted by industry. That means real estate developers, lenders, governments, and development banks need to support the growth of planetary health cities,” added Fall, who is also faculty co-director of the Institute for Planetary Health Practice Program and a driving force behind the Planetary Health Cities concept and symposium.

David Martin, CEO of Miami-based development firm Terra, explained how his company works with communities to build sustainable neighborhoods. Terra is leading several public-private partnerships in South Florida to transform underutilized properties into parks and mixed-use residential spaces. Creating walkable, transit-oriented, and diverse urban core units is a key objective. Martin says improving the surrounding community directly enhances the value of the firm's building projects. "We're always trying to make the neighborhood better. We feel as a business case, if we make the neighborhood better, we're just making our asset better," he said.

The big problem of microplastics

Many common building and decorating materials used in homes, offices, and other facilities become long-term environmental pollutants. “Packaging is the largest use of plastics. Building products are the second highest use and growing rapidly,” said Habitable CEO and symposium presenter Gina Ciganik. She says nearly 58 percent of all the microplastic contamination in the oceans comes from latex paint. In addition, carpeting, which contains nylon fibers, contributes another 1.2 million tons of plastic to the environment each year. That equals all plastic bags, water bottles, and straws thrown away each year.

 Microplastics are increasingly recognized as a potential hazard to human health as studies suggest these pollutants increase inflammation and damage to the respiratory, reproductive, and digestive systems. Habitable is seeking holistic scientific and economic solutions to reducing global chemical pollution. 

 According to Ciganik, Habitable is disrupting the growth of plastics in the real estate sector by developing guidelines for builders to replace plastic products with more sustainable or eco-friendly materials. “Fifty years is an average lifespan for a building, carpet tends to be about three years,” she said. “We really need to change our mindset on how we keep things in use, and how we repair them or not.” 

Better cities lead to better health

Johns Hopkins University launched the Institute for Planetary Health in 2024 to address the degradation of the Earth’s natural systems and their impacts on human health and well-being. The institute brings together faculty, students, and staff from across Johns Hopkins to find solutions to critical environmental issues and their impacts on humanity.

“It’s like we packed our children into a giant bus, the bus is driving towards the edge of the Grand Canyon, and we just realized that the bus driver is asleep at the wheel? This is our moment to wake up the bus driver,” Myers explained. “If we're effective at doing that, there's a very bright future in which we essentially rethink the systems that we use for just about everything from food production, energy production, circular economy, manufacturing—and yes—how we build and design our cities. The conversation that we're having today is about waking up the bus driver.”

“We hope that this is the beginning of creating something new that's focused on health and better quality of life, better buildings, and a better real estate industry,” added Fall.