Building healthier communities to address the effects of climate change

The effects of climate change on our cities and homes becomes clearer with every extreme weather event and subsequent year of record-setting heat. And while these facts aren’t fun in nature, we can use them to better serve our communities moving forward—and we’ve been actively engaged in doing just that. Given that more than half of the global population lives in cities, communities across the globe are seeking ways to reduce the impacts of increasing temperatures, intensifying storms, rising sea levels, and increasing levels of air pollution. Lasting, effective changes can be made if we make the conscious effort to strategically consider the immense impact climate change has on health, the economy, and the price our inaction has on human wellbeing.

Extreme weather events and population displacement have already resulted in conversations about the economic impacts of climate change, whether it be loss of property or strains on the funding of our social safety nets. Climate change’s impact on human health is also threatening our economic stability. Increased heat and extreme weather also create unhealthy living environments. Air pollution and pest-borne illnesses are increasing, as are related rates of asthma, allergies, and infectious disease—all of which can lead to higher healthcare spending. Drought and famine bring population displacement and foster civil unrest over resource scarcity, while also affecting the physical and mental health of the world’s most vulnerable populations. While that’s a lot to digest, there is hope. The more we learn, the more we strengthen our understanding of climate change and our collective plans to take what we know and put it to good use as we work to concertedly foster stronger, healthier communities.

With that in mind, let’s put it to mention that we do in fact have the opportunity to build healthier, more resilient cities with infrastructure that can alleviate the impacts of climate change—on both our physical environment as well as on our health. Expanding research into the health impacts of continued climate change and the importance of urban form will ensure that we have the knowledge to make our cities as livable and resilient as possible and will ultimately leave our institutions better positioned to help cities and communities weather the challenges of the future.

chapter 1

Extreme weather and the effects of climate change on our communities

Increasing global temperatures threaten the potable water supply in Lusaka, Zambia. Extreme weather events threaten the agricultural industry in Nicaragua. Drought and famine in South Sudan exacerbate regional conflicts. In the United States, climate change has increased the threat of extreme weather, damaging wildfires, and flooding in coastal regions. The above are just some examples of the effects climate change is having all over the world. These effects are happening everywhere.

As the rise of greenhouse gases continues to change our climate, communities are feeling the strain on many levels, from testing the limits of infrastructure to displacing entire communities. Today’s cities were not built for the climate we now live in and fundamental changes to our cities and lifestyle habits must be made in order to adapt and respond to our rapidly changing climate.

Researchers from the Boston University School of Public Health (BUSPH) and the University of British Columbia School of Population and Public Health found that a large number of heat-related deaths occurred during moderately hot temperatures in traditionally more temperate climates – areas whose infrastructure and the population is not prepared for extreme weather and heat. The definition of “dangerous” or “extreme weather” differs by location. Some structures and cities lack important precautionary tools, such as air conditioning and cooling centers, to help protect their communities from these extreme heat events. Creating precautionary plans in advance of extreme heat events is particularly important for vulnerable populations such as older adults, pregnant women, low-resourced populations, and outdoor workers. The problem is structural, yet the impacts are on human health.

Climate science research has expanded beyond the analysis of environmental impacts; researchers now have a strong body of evidence showing how climate change is impacting cities and the people who live within them. Urban areas often seem vastly removed from the natural world, but they are not immune.

Extreme temperatures and deficiencies in urban planning that are unable to adapt to these temperatures are two aspects of climate change in which cities are now encountering. Lack of green spaces and reflection from dark impermeable surfaces, like asphalt, contributes to increased temperatures compared to surrounding rural areas. Experts label this phenomenon as “urban heat islands”. Air conditioning is a contributing factor to these urban heat islands as they significantly increase energy usage thus continuing the cycle. Rising sea levels, stronger storms, wildfires, and air and water pollution exceeding toxic levels are challenging cities to identify solutions to mitigate these threats and rebuild infrastructure that is adaptable to changing climate patterns.

Other resources:
“Heat May Kill More People in the US Than Previously Reported”

“The nexus between urbanization and PM2.5 related mortality in China” 

“Impacts, adaptation and vulnerability”, IPCC 5th assessment report

chapter 2

Healthy homes and how public health policy can create healthier living spaces

The UN predicts that 68% of the world population will live in urban areas by 2050. This growing demand for additional housing in urban settings is increasing due to better job access and educational opportunities. The increase in demand for housing also increases the need for improved living environments to protect the health of these communities and the environment such as clean water, airflow, and heat and/or cooling sources.

A growing volume of research has identified ways in which public health policy and urban planning can be altered to create cities and living spaces that are adaptable to climate change and alleviate the resulting health impacts. This research helps to discover more efficient means of temperature regulation, how to provide cleaner air within homes, and how the benefits of increased access to green spaces and public transportation can reduce greenhouse gas emissions and reduce the detrimental health impacts from air pollution. For example, tree-lined streets create a cooling effect on surrounding buildings.

Government Agencies, such as the US Housing and Urban Development, have published checklists to help people understand what makes a healthy home setting with attributes such as a:

• dry environment — Wet conditions can increase risk of asthma, mold-related illness, and other respiratory problems.
• pest-free environment — Cockroaches, rats, and other pests can spread disease to humans.
• chemical and contaminant-free environment — The presence of lead, asbestos, volatile organic compounds, pesticides, and other contaminants in and around the home, including tobacco smoke, increase the risk of diseases like autism, Alzheimer’s, and cancers and can lead to premature death.
• well-ventilated environment — Poor airflow is a factor in the development of some infections and chronic diseases like lung cancer and contributes to the risks mentioned above. 
• safely-designed environment — Unsafe staircases, lack of railings, and other design methods increase the risk of falls in older adults.

While these checklists detail much of the risks within a housing unit, they neglect the larger environmental factors outside that can influence health inside the home, especially in multi-unit housing. Boston University School of Public Health faculty member Dr. Jonathan Levy, whose focus is in urban environmental exposure, health risk modeling and healthy homes, has identified a number of external factors to watch for throughout a building and a neighborhood. When pests, poor ventilation, and mold are present in a building or a neighborhood, it can have negative impacts on the surrounding housing units, Levy has found. In turn, improvements to the neighborhood improve health outcomes.

Walkable neighborhoods create opportunities for outside physical activity. Tree-lined streets have a cooling effect on the buildings. Research even indicates creating smoke-free environments within apartment buildings and public housing can have a positive effect on health, even in people who are not smokers.

Dr. Daniel Brooks, a faculty member in the department of epidemiology at Boston University School of Public Health, and his team reviewed the implementation approaches used by public housing authorities with smoke-free policies, particularly those who voluntarily adopted the policy. The team looked at this voluntary adoption to provide guidance for other public housing authorities who are in the process of implementing smoke-free policies with the goal of gaining the support of residents, minimizing negative consequences of this public health policy implementation, and maximizing the health benefit for everyone in the community.

Brooks and his team used the information collected from site visits and surveys completed by residents to develop a website to guide the 2,700 public housing authorities nationwide that had yet to adopt the mandatory smoke-free policies. By creating a how-to guide, public housing authorities were more easily able to implement these changes to ensure lasting and beneficial change within public housing.

The same kind of work can be done to help public health policymakers, planning departments, housing authorities, and others within urban planning to mitigate other external environmental attributes caused by climate change, whether that be reducing the impacts of extreme heat through increased vegetation throughout neighborhoods or reducing traffic congestion to alleviate air pollution.

Other resources:
Expanding on the Healthy Homes Checklist

chapter 3

Recognizing vulnerable populations and addressing health inequities

The places that are most vulnerable to climate change and the resulting health risks are located in areas with the limited capacity to rapidly and effectively respond to climate change. These locations are often less developed areas with weak infrastructure and populations of low socio-economic status. It is important to note that effects of climate change are not just an issue in developing countries, communities within the US and other developed nations are at high risk too, especially those facing health disparities due to structural racism. In turn, the people who live in these locations are at greater risk to experience the health impacts that come with air pollution and other impacts of climate change.

The COVID-19 pandemic highlights how social disparities are directly related to greater health risks. A team of faculty members, researchers, and students at Boston University School of Public Health showed COVID-19 disproportionately impacted Massachusetts’ communities of color through development of an interactive mapping tool that offers visual and analytical insight into regions of vulnerability based on a range of health, economic, environmental, and social factors. The interactive map became part of the Massachusetts Office of the Attorney General’s report, “COVID-19’s Unequal Effects in Massachusetts,” which called for changes in policy to remedy environmental injustice, not just to help battle COVID-19, but “as we are all facing another threat, even greater than COVID-19—climate disruption.” This work was supported by the NIH and a gift from Google. 

During a press conference unveiling the report, Dr. Jonathan Levy, faculty member and chair of the department of environmental health at Boston University School of Public Health, said, “Environmental justice communities have been disproportionately burdened by COVID-19, because of a combination of factors ranging from workplace exposures to overcrowded housing to environmental exposures that lead to higher rates of respiratory and cardiovascular disease. Only by understanding the influence of environmental exposures can we protect vulnerable populations from this pandemic and future crisis, including climate change.”

Climate impacts on elderly populations

Dr. Patrick Kinney, Beverly Brown Professor of Urban Health and faculty member in the environmental health department at BUSPH, has analyzed the risks of extreme heat in urban areas and found that the risk of dying from heat in New York City declined 65% from the early 1970s to 2006 as the proportion of households with air conditioning surged. However, the risk is still quite pronounced for elderly residents.

“It puts a stress on anybody’s body, but if you’re old and frail, it’s harder,” Kinney told The Independent. In addition, “certain medications older people take, for blood pressure or cholesterol, reduce the body’s ability to thermo-regulate.” Lack of mobility and social isolation exacerbate these risks, making it more difficult to get help when needed. Community organizations and public health policies that respond to the growing need for extreme heat response in urban areas can help prevent costly medical interventions with simple, inexpensive measures like providing transportation to cooling centers.

Other resources:
“Older People Are Contributing to Climate Change, and Suffering From It”

chapter 4

Climate change and health 

With greenhouse gases and global temperatures reaching unprecedented levels, the fields of climate science, environmental health, and epidemiology have converged on a number of fronts to pinpoint the harmful effects of climate change on human health. Leaders in this field of research continue to find links between rising temperatures and negative health outcomes. Published research has also shown a connection between climate change and the rise in infectious disease, food insecurity and malnutrition, allergies, and stress-related mental health disorders.

How the major impacts of climate change lead to increased health risks

Climate change can bring extraordinary changes to ecosystems and weather patterns, which have adverse effects on human health and wellbeing. Some examples of these adverse changes include: 

• expanding geographic range of mosquito and tick populations — Rising temperatures are increasing disease carrying pest populations and the spread of vector borne illness, including malaria, dengue fever, West Nile virus, and Lyme disease.
• threats to safe food and water resources— Research has shown climate change is also increasing food and waterborne diseases such as salmonella, cholera, dysentery, and schistosomiasis in cities and rural areas around the world. 
• food insecurity — Drought and flooding are eroding or creating inhospitable soils, increasing the threat of famine and food insecurity, thus impacting the food supply chain to cities, driving human migration and creating refugee crises across the world.
• increased allergens and asthma — Wildfires, drought, and CO2 emissions from factories and cars have been tied to respiratory illness. Additionally, rising temperatures and increased CO2 emissions have been linked to increased pollen production and longer allergy seasons.
• higher rates of cardiovascular disease — Rising temperatures and extreme heat events have been tied to increased risk of heart attack.

The slower-moving impacts of climate change, often related to human activity such as expanding urban development into undeveloped areas, are emerging in cities throughout the U.S. and around the world. Research into these health impacts has drawn interest from across Boston University, including the School of Public Health, School of Medicine, and the College of Arts & Sciences.

Rising temperatures and indirect health impacts

Here in New England, Lyme disease has emerged in recent decades as a growing health threat which research indicates is closely tied to changing climates.

“In the US Northeast, we worry a lot about Lyme disease,” Dr. Gregory Wellenius, a Boston University School of Public Health professor of environmental health told The Brink. “Because of the warming temperatures, the ticks that are vectors for Lyme disease now survive further north in areas that they didn’t used to be able to survive.”

Deer ticks found in forests and grasslands across the US can carry bacteria that causes Lyme disease. It has been particularly wide-spread in the Northeast, in some instances causing serious, long-lasting, and debilitating symptoms. Researchers at Boston University have found Lyme disease–carrying ticks are quickly expanding their numbers and range in large part because a warmer climate has allowed the ticks to reproduce at higher numbers, grow faster, and expand into regions that were once too cold.

“Climate change is not a problem of the future or of people far away—it’s here, right now,” Wellenius said. “It impacts our families and communities today and will continue to do so, and those effects will get more pronounced. Anything we can do to minimize future climate change is likely to have immediate health benefits now and in the future.”

Other resources:
“Ticks and Mosquitoes, Infectious Disease Carriers, Are Expanding Their Range”

“Allergy Season is Getting Longer — blame it on Climate Change”

BUSPH Program on Climate and Health

chapter 5

Evaluating and measuring climate effects on our health

As the field of climate science research continues to expand, the world’s largest research institutions are investing resources into understanding how these environmental changes will alter the way we live. Boston University School of Public Health recently launched the Program on Climate and Health, dedicated to studying the impacts of climate change on human health. Dr. Gregory Wellenius was recently appointed the head of the program, and was previously involved in a number of studies examining this issue. 

In 2019, Wellenius was the senior author of a study looking at the connection between extreme temperatures and low birth weight. Previous studies on the impact of temperature on birth weight had yielded mixed results, yet the observational study Wellenius published in June 2019 in Environmental Health Perspectives uses the largest dataset to date to find there is likely a connection, especially in areas with colder climates.

Dr. Patrick Kinney agrees more research is needed. “Temperature as a risk factor [for pregnancy outcomes] is something people have begun looking at only recently,” he said in an article in Medscape Medical News. “It’s a small literature so far, but growing rapidly as people become more aware of the impacts of climate change.”

Beyond faculty researchers examining the connection between climate change and health, academic programs like the Boston University School of Public Health Master of Science (MS) in Population Health Research: Climate and Health are being developed to provide students with an in-depth understanding of the far-reaching health impacts of climate change and how to prepare communities for them. With a curriculum focused on quantitative research methods necessary to evaluate the benefits of climate mitigation and adaptation measures, BUSPH aims to train the next generation of researchers to address this pressing issue.

Other resources:

“BUSPH MS Program on Climate and Health“

chapter 6

Quantifying the impact of a reduction of greenhouse gas emissions and the health effects of climate change

As researchers seek methods to mitigate the negative health impacts of climate change, an obvious solution is to reduce the amount of harmful greenhouse gases and slow the pace of climate change.

Dr. Patrick Kinney, the senior author of a study in Environmental Research Letters found that by eliminating greenhouse gas emissions in the Greater Boston area, more than 200 deaths could be avoided and $2.4 billion saved in medical costs each year from reductions in cardiovascular and respiratory illness. 

“In showing the substantial health and economic benefits that clean air can bring to Boston area residents, this study demonstrates that climate action isn’t just about saving the planet; it’s also about making us healthier,” said Kinney.

Kinney’s research has shown that long-term exposure to slightly elevated levels of air pollution can be linked to accelerated development of lung damage, even among people who have never smoked. Published in JAMA, the study revealed a connection between ambient air pollutants to a faster progression of lung disease and changes in lung function in the general population.

Boston has made a commitment to be a carbon-neutral city by 2050, making measurable strides to reduce greenhouse gas emissions. While so much of our conversation on climate change has been focused on rising sea levels, drought, extreme weather, and the structural and economic damage these outcomes bring, the research being done at Boston University School of Public Health shows that climate change has a hugely negative effect on health outcomes. Research from BUSPH also shows that lowering carbon emissions in the construction, transportation, and energy sectors can help stave off the dangerous health impacts of air pollution and save the region billions of dollars in health care costs and lost income due to illness.

As we look to enact solutions to our climate crisis in the years ahead, the impacts on human health, particularly in areas of low-resources and within vulnerable communities, must be part of the conversation. Making changes to care for the community’s health today and reducing climate impacts in the future go hand in hand.

Other resources:

“How Reducing Greenhouse Gas Emissions Affects Public Health and Helps Reduce Healthcare Costs”

“A Zero-Emissions Boston Could Save 288 Lives and $2.4 Billion Annually”