Perspective Chapter: Climate Change and Health Inequities

Abstract

Climate change poses an imminent danger to health and humanity. Climate change via the drivers of rising temperatures, increasing natural disasters, rising sea levels, and air pollution pose significant challenges for the healthcare system and negatively impact patient health. These health risks include increased temperature-related morbidity and mortality, air-pollution-related health effects, and frailty due to respiratory and cardiovascular impacts from heat and weather events. Increased adverse birth outcomes have also been associated with climate change. Urbanization, exposure to increased heat levels, and exposure to increased natural disasters and extreme weather events also lead to higher levels of injury and mortality, increased health system trauma burden, and increased demand on the healthcare system’s capacity. While all populations are impacted by climate change, vulnerable populations are disproportionately at risk. The impact on global health will be tremendous unless significant action is taken to reduce carbon emissions and curtail climate change.

1. Introduction

Climate change has been described as a fundamental threat to human health [1]. It has a far-reaching impact and has been identified as a global threat to humanity in the 21st century. The health of the planet plays a role in sustaining human health. Dr. Margaret Chan, Director General, World Health Organization, stated, “A ruined planet cannot sustain human lives in good health [2].”

Climate change poses an imminent danger to humanity, and the discussion on its impact on population health outcomes can no longer be postponed. The World Health Organization (WHO) estimates that climate change will cause an additional 250,000 deaths per year from malnutrition, malaria, diarrhea, and heat stress alone [1]. Additionally, the direct damage costs to health are projected to be between US$2–4 billion annually by 2030 [1].

All populations and communities are affected by climate change, but vulnerable populations are disproportionately at risk [3]. In a 2018 report, the WHO stated that “climate change is the greatest threat to global health in the 21st century” and that “vulnerable populations, including children, pregnant women, and the elderly, are most at risk” [4]. This increased risk is compounded by the integration of structural racism into the built environment within the United States, which exacerbates existing inequities in the social, political, and ecological determinants of health [5, 6].

The health industry significantly contributes to the global carbon footprint, accounting for nearly 5% of greenhouse gas emissions [7]. The US health sector contributes substantially to the climate crisis, responsible for 8.5% of US greenhouse gas emissions [7]. This impact of healthcare on the climate crisis has prompted leading healthcare organizations globally to address the impact of the healthcare sector on climate change and climate change’s impact on the health of the global population [8, 9].

While several well-known examples exist in US history of the disparate and unequal valuation of specific communities, there are also examples related to the impact of climate change on marginalized and vulnerable populations [10]. Redlining and other racist practices have disproportionately increased heat exposure, heat islands, air pollution, asthma, premature birth, and other health sequelae for communities of color and other marginalized populations [10, 11, 12]. The increased impact of natural disasters on communities of color, such as in the aftermath of Hurricane Katrina in New Orleans and Hurricane Maria in Puerto Rico has been reported [11]. Such examples further reinforce the critical roles of equitable policies in combating racism and environmental and social injustices.

1.1 Climate vulnerability

Climate vulnerability explains the sliding scale of impact individuals and communities have during climate health crises based on the level of privilege society has provided them [13]. The climate health crisis impacts all persons; however, some communities are impacted more immediately and severely than others. Individuals seen as being at the top of the racial-ethnic caste are generally allocated privileges of access and believability when voicing concerns for their safety [14]. This sliding scale of believability and privilege translates into less vulnerable or privileged populations having larger public health budgets and financial resources in general to educate and prevent catastrophic outcomes. These resources directly translate into community capacity and intragroup efficacy in these groups with intersectional privilege.

1.2 Socioeconomic status

Socioeconomic status refers to the income level a family or individual has access to in relation to the cost of living and their family size. Having financial freedom and being at a higher socioeconomic status allows individuals the freedom to proactively plan for climate change challenges and relocate to locations that have more resilience and capacity to combat climate change. For example, a study completed in Southern Nevada found that communities with lower incomes live in areas with a lower cost of living. In some cases, exposure to mold and pest infestations exacerbate asthma. Exposure to Radon and asbestos can increase the risk of lung cancer. These communities that have close proximity to pulmonary aggravating factors may also have less access to medical care and less financial investment in public health strategies. Often, persons and families of lower socioeconomic status feel less empowered to report concerns or self-advocate due to the power differential created between the owners, those financially profiting from the land use, and themselves, the renters. Persons with low socioeconomic status often do not have a lack of awareness of the environment and climate change. Still, they are hyper-aware of the retaliation present when speaking out about the state of their living environment, such as increasing rent prices and nonrenewal of leases without an alternative living situation, if they voice their concerns [15].

One example of the socioeconomic status and power dynamic struggle is the impact of oil and gas companies on rural communities. Often, oil and gas extraction occurs in lower-income communities. These communities can be exposed to poor water quality, fracking earthquakes, and unpleasant smells [16]. These factors make the surrounding community less likely to house wealthy persons with social capital. However, the oil and gas industry can provide a source of immediate income for those living in proximity to the extractive process. The steep financial gradient between the oil and gas industry and people cohabiting in the same space with the industry can make a tempting scenario for community members to accept the immediate benefit of affordable living costs for the perceived delayed risk of adverse health outcomes.

1.3 Intersectionality

The ability of an individual or community to occupy more than one identity is described as intersectionality [17]. Often, intersectionality is used to describe various marginalized communities that one identifies with. Understanding these multiple intersections can provide a more comprehensive understanding of the social, political, and ecological determinants of health’s impact on community and individual health. Viewing the impact of climate change through the lens of intersectionality helps the climate clinician better understand who is impacted the most and to what degree by climate change. Hurricane Katrina, which first struck on August 29, 2005, on the United States Gulf Coast, negatively impacted lower-income Black communities. The inadequate emergency response system and severity of the hurricane, category 5, resulted in significant structural damage, delayed access to emergency services, and significant loss of life [18]. As the catastrophic event made headline news, some religious organizations blamed LGBTQIA+ populations for causing the event, and adequate shelter considerations were not provided for transgender and gender non-conforming individuals. Inadequate evacuation plans and accessibility made it challenging for persons with disabilities to evacuate from the area [19]. The lack of planning caused limited access to medications and medical devices that were medically necessary for some individuals living in the impacted area.

When viewed in silos, each marginalized population faced unique challenges in combating the challenges of climate change and the fallout from Hurricane Katrina. In reality, many of those impacted were not siloed into one marginalized identity but lived in the intersection of multiple marginalized identities. Understanding the intersections of marginalized populations helps the climate clinician understand climate vulnerability. Often, populations and individuals who live within the intersectionality of multiple marginalized identities lack the access and resources to quickly adapt to a climate change event and prepare for impending events. The lack of a robust response by these communities lies not in a lack of desire or understanding of the implications of climate change in the community but in the health inequities that exist and have a catastrophic impact during climate change events.

Lack of planning can also leave vulnerable populations, such as infants, without access to safe nutrition. Communities that lack adequate lactation and breastfeeding plans can leave infants under 6 months of age vulnerable to nonpotable water and infections more common in formula feeds when appropriate planning for vulnerable populations is not considered [20]. Research is needed to elucidate the impact of intersectionality on marginalized communities fully. An example of a toolkit to incorporate intersectional gender perspective into implementation research projects is the Tropical Disease Research (TDR) Implementation Research Toolkit [21]. The TDR is co-sponsored by the United Nations Children’s Fund (UNICEF), the United Nations Development Programme (UNDP), the World Bank, and the World Health Organization [22].

2. Environmental justice

Environmental Justice has been described by Dr. Robert Bullard, considered the “Father of Environmental Justice,” as “the principle that all people and communities have a right to equal protection and equal enforcement of environmental laws and regulations” [23]. Environmental justice refers to the fact that there is a disproportionate impact and burden of environmental risks, including climate change and air pollution, on vulnerable and frontline populations such as low socio-economic households and communities of color. The intersectionality of these marginalized groups may serve to worsen their disproportionate burden of climate change and its impact. The American Public Health Association describes environmental racism as any environmental policy, practice, or directive that disproportionately affects or disadvantages individuals, groups, or communities based on race or color [24].

Historical policies such as redlining in the United States have harmed Black Indigenous and People of Color (BIPOC) communities. Redlining policies codified segregation and unequal distribution of funds to different neighborhoods across a community [25]. Additionally, redlining policies restricted BIPOC families from living in certain neighborhoods and accessing resources to build capital in their community, such as home loans. Today, the impact of redlining allows for hazardous chemicals, unfavorable plant processing operations, waste disposal, and limited green spaces to occur near BIPOC communities. In a practical sense, this means that aside from overt racial discrimination, these marginalized communities are suffering from a lack of climate change resilience due to policies that often predate their existence. That is, the policies created when their grandparents were attempting to buy homes and build communities in a post-World War II era are still driving health outcomes for the community’s inhabitants today.

A study by Hsu et al. found that the average person of color in the United States lives in a census tract with higher surface heat than non-Hispanic whites in all but 6 of the 175 largest urbanized areas in the continental United States [26]. This was also demonstrated for people living in households below the poverty line, compared to those at more than two times the poverty line.

Heat islands are urban areas with higher temperatures compared to surrounding areas. They are also associated with a lack of green spaces. Higher percentages of Black and Hispanic people reside in these heat islands in the US South, Southwest, and West and are projected to experience more extreme heat.

The construction of the modern United States highway system is another example of environmental racism. A majority of these highways were constructed through frontline communities of color and low-income communities, which lead to increased exposure to traffic and air pollution and disruption and destruction of these neighborhoods [27]. A study of transportation-related fine particulate matter air pollution in the Northeast and Mid-Atlantic found that communities of color breathe 66% more of it from vehicles than white residents [28].

Air pollution exposure also demonstrates an unequal and disproportionate impact on frontline communities. Factories are more likely to be placed in poor and underserved communities. These vulnerable communities are more likely to live near polluting power plants and hazardous facilities. They are also more likely to experience cumulative adverse health effects from exposure to pollutants. Additionally, studies demonstrate an increased impact of air pollution on maternal mortality in women of color.

2.1 Historical context of environmental injustices

Environmental injustice within Black and Brown communities have been demonstrated over 40 years of research which shows that these communities experience the worst environmental pollution and degradation [29, 30]. Over this time, these same communities continue to experience the greatest impact of “climate-change fueled risks like hurricanes, flooding, vector-borne illness, and wildfires” [30]. Although the start of the environmental justice movement needs to be clarified, the first documented research on environmental injustice was captured by Dr. Bullard in the 1970s [30]. When residents of a Black middle-class neighborhood in Houston, Texas, learned that the state planned to permit a solid-waste facility in their community, they determined that further investigation was needed [5]. Dr. Bullard found that over 80 percent of the city’s waste—was indeed situated in Black neighborhoods, while only 25 percent of Houston’s population were Black [30]. Local groups nationwide have similarly complained about inequitable land uses for decades [5].

“In the 1980s the environmental justice movement developed into a national social and racial call to action that inspired communities nationwide to seek social justice and environmental protection” [31]. Per reports, in 1982, a small, predominantly Black community in Warren County, North Carolina was identified as the host location for a hazardous waste landfill to accept PCB-contaminated soil that resulted from illegal dumping of toxic waste along roadways [29]. The state of North Carolina reportedly considered several potential sites to host the landfill and ultimately settled on the small Black community [29]. Although the Warren County protest was not successful in preventing the approval of the disposal facility, it is considered to have fostered a national start to the environmental justice movement [29]. The Toxic Waste and Race study in 1987 found that race was the most significant factor regarding the siting of toxic waste facilities with nearly 3 of every 5 African-Americans or Hispanic Americans residing in proximity to a hazardous waste site [29].

3. Health equity and health impacts of climate change

Climate change via the vectors of rising temperatures, extreme weather, increasing CO2 levels, and rising CO2 levels has a significant and wide-ranging impact on human health (Figure 1). Many health effects of climate change disproportionately impact frontline and vulnerable communities.

Figure 1.

Impact of climate change on human health (CDC). https://www.cdc.gov/climateandhealth/effects/default.htm [32].

3.1 Climate change exposures

3.1.1 Heat

The IPCC’s sixth assessment report, published in 2021, found that human activities have caused approximately 1.1 degrees Celsius of warming from 1850 to 1900 due to greenhouse gas emissions [33]. Increasing global warming is projected to increase the number and intensity of heat extremes. Exposure to extreme heat is a significant health hazard. Those most susceptible to the health impacts of extreme heat exposure include babies and children, older adults, and people with co-existing health conditions. Heat exposure increases the risk of mortality from cardiovascular and cerebrovascular disease, with heat-related deaths in people older than 65 years of age reaching a record high in 2019 with an estimated 345,000 deaths [34].

3.1.2 Air pollution

The National Institute of Environmental Health Sciences (NIEHS) reports that air pollution accounts for 1 in 8 deaths worldwide, while data from the World Health Organization (WHO) shows that almost all of the global population (99%) breathes air with pollution levels that exceed the WHO guideline limits, with low and middle-income countries suffering from the highest exposure [35, 36]. Climate-related extreme weather events, such as worsening wildfires, also increase air pollution levels. Heat also increases ground-level ozone, a harmful air pollutant known as smog. Ground-level ozone occurs when air pollutants such as volatile organic compounds and nitrogen oxides mix with heat and sunlight.

Those most vulnerable to the health effects of air pollution are typically those exposed to the highest levels. In the United States, this includes low-income communities and communities of color, which are more likely to be located near polluting facilities and highways. Additionally, children and older adults, as well as those with underlying health conditions such as asthma, are at an increased risk [37]. Globally, the risk is highest for those in low- and middle-income countries, with the highest mortality rates attributed to air pollution in East and South Asia and sub-Saharan Africa [38].

3.1.3 Extreme weather

The impact of natural disasters on healthcare access and healthcare is significant. This includes increased adverse birth outcomes, higher trauma burdens, mental health impacts, infrastructure damage, and burdening of the healthcare systems [39]. Mitigating these impacts through significant policy changes and evaluating the social and political determinants of health that have contributed to these inequities is paramount.

There are a significant number of natural disasters each year. In 2019, there were 396 disasters worldwide globally. These disasters were responsible for more than 11,000 deaths and affected the health of more than 95 million people [40]. The cost is significant, costing the economy billions of dollars. The most common natural disasters encountered are floods and storms, accounting for approximately 68% of the worldwide impact [40].

Extreme weather events, rainfall, wildfires, droughts, and hurricanes associated with climate change may lead to human population displacement, increased trauma burden, and increased health system burden [37] Additionally, increased fires and flooding associated with climate change can affect access to electricity supply and destroy roads and clinics, leading to the loss of needed infrastructure for delivering healthcare to vulnerable populations.

The most vulnerable patients are affected most significantly by disasters and extreme weather events, such as children, pregnant women, elderly individuals, those with limited resources, and those with chronic illnesses and allergies. Mitigating these impacts requires significant changes in policy and evaluation of the social and political determinants of health that have contributed to these inequities [41].

Often, these populations are also the most under-resourced populations who may not have the resources required for disaster mitigation strategies such as relocation or other preparation strategies. Natural disasters may also serve to worsen health disparities, as seen recently in the impact of Hurricane Katrina. Communities of color and under-resourced communities were most affected by the impact of the storm in Louisiana. The intersection of risk from extreme weather and climate events, physical hazards, the extent of exposure, the vulnerability of individuals and communities, and the capacity to prepare to manage and recover from extreme events is the central theme when viewing this through a health equity lens [40]. The placement of infrastructure and the migration of people into vulnerable regions in combination with climatological or meteorological events account for the impact of natural disasters [40].

The effects of natural disasters on health have a wide range, including heat exhaustion, traumatic injuries, respiratory illnesses due to mold from floods, and impact on perioperative care. Extreme weather events affect perioperative care by increasing the frailty of the patient. Loss of access to healthcare systems by the destruction of roads and infrastructure impacts access to medications and potentially lifesaving healthcare. Additionally, there are increased adverse birth outcomes, higher trauma burdens, and damage and burdening of the surgical infrastructure caused by disasters and extreme weather events. Extreme weather has been associated with increased injuries, fatalities, heat-related illness, death, and cardiovascular failure. Water quality impacts include increased bacteria within water sources, decreased access to potable water, and increased vector-borne diseases related to stagnant or poor-quality water sources. Emergency evacuations also pose an extra health risk to children, older adults, disabled patients, and those who are under-resourced. Exposure to extreme weather has been demonstrated to result in injury, death, and displacement. Weather events impact power and phone lines, cause damage or destruction of homes and reduce the availability of safe food and water. They may also damage roads and bridges, impede access to medical care, and separate patients from their medications [37].

Severe weather events also have significant mental health impacts [42]. Exposure to disasters is correlated with increased stress and mental health consequences, including increased suicidal thoughts, depression, and post-traumatic stress disorder [43, 44, 45]. Cianconi, Betro, and Janiri noted the introduction of new terms such as ecoanxiety, ecopsychology, and ecological grief and that the phenomena may be transmissible to later generations. Pregnant women and postpartum women have an increased risk for severe stress and other adverse mental health outcomes associated with weather-related disasters associated with climate change. Additionally, severe maternal stress can increase the risk of adverse outcomes such as pre-term birth [46].

3.2 Global impact of climate change on worsening health inequities

Climate change, however, has a global impact and contributes to global health inequities. Record temperatures have been seen globally. In 2020, it was estimated that there were 3.1 billion more person-days of heatwave exposure in persons 65 years and older [34]. Additionally, there were an estimated 626 million more person-days of heatwave exposure in children younger than 1 year [34]. The most affected populations are the socially disadvantaged, elderly, and youth populations. Populations in countries with low and medium levels of the UN-defined human development index show the highest increase in heat vulnerability in the past 30 years. Those risks were worsened by the lower availability of cooling mechanisms and green space [34].

Rising average temperatures and altered rainfall patterns also worsen food and water insecurities, affecting underserved populations globally. In any month in 2020, it was estimated that up to 19% of the global land surface was affected by extreme drought. This impacted the yield potential of major crops and worsens the risk of food insecurity. Additionally, malnutrition risks rise, significantly impacting the population’s health [34]. Climate change impacts food insecurity and plays a role in decreasing maternal and infant health. Increased heat and extended drought lead to crop failures and unstable crop yields, further contributing to malnutrition, low birth-weight infants, increased disease burden, and decreased maternal energy [47].

3.3 Health impacts of climate change

The existing inequities and vulnerabilities of specific populations expose these populations to disproportionate risks (Table 1). Health impacts by climate change vectors include:

Health Impact	Climate Change Vector/Exposure Pathway	Inequities/Vulnerable populations
Heat-related illness (heat stroke, heat exhaustion, etc.)	Heat	Elderly, children, lower socio-economic populations, farm workers, student athletes
Cardiac Diseases (myocardial infarction, stroke, atherosclerotic plaque disease etc.)	Heat; Air Pollution	Elderly, children
Kidney Disease	Heat	Agricultural workers, End-stage renal disease
Mental Health (Depression, Anxiety, Violence, PTSD, Suicide)	Heat; Extreme Weather	Underlying mental health conditions, pregnant women, children, migrants, refugees, elderly, low-socioeconomic populations, first responders
Allergies and Respiratory Health (Asthma, Lung Cancer, etc.)	Air Pollution; Heat	Low socioeconomic populations, proximity to highways and factories, underlying respiratory illnesses (e.g., COPD, Asthma)
Pregnancy and Infant Risks (Preterm labor, low-birth weight, etc.)	Air Pollution; Heat; Extreme Weather; Vector Disease Transmission	Living near highways and/or factories, low-income communities, communities of color, poor access to care
Infectious Disease (increased disease transmission, increased water-borne infectious diseases)	Heat; Extreme Weather (Flooding, Drought)	Low-socioeconomic populations, coastal communities
Food and Water Insecurity	Heat	Women, rural communities, low-income global communities
Disruptions to care (Decreased access to care, disruption in access to care and medications, power disruption etc.)	Natural disasters (Wildfires, hurricanes, flooding)	Elderly, chronically ill, lower socio-economic populations, poor access to care populations

Table 1.

Health impacts via climate change and inequities and vulnerable populations.

3.3.1 Heat-related illness

Heat-related illnesses cover a wide range of health consequences, from dehydration to heat stroke. Heat stroke, one of the most hazardous health conditions, occurs if the body temperature rises to about 104°F (40°C) [48]. Heat stroke is characterized by central nervous system dysfunction (damage to the brain), as well as multiorgan failure, including damage to the heart, kidneys, and muscles. Heat stroke is most likely to impact the elderly, whose ability to adjust physiologically to heat stress is diminished. Young children are also at high risk due to multiple factors, including their high ratio of surface area to mass (which leads to an increased heat-absorption rate) and their lower sweating rate (used to dissipate heat).

3.3.2 Cardiac disease

Both heat exposure and air pollution pose a risk to cardiovascular health [49]. Thermal stress and air pollution cause acute and chronic physiologic changes within the circulatory system, increasing inflammation and cardiovascular demand [50]. The stress on the cardiovascular system increases blood pressure, impairs clotting responses, and predisposes vulnerable individuals to atherosclerotic plaque rupture, which can result in a heart attack or stroke [39].

3.3.3 Kidney disease

Extreme heat exposure increases the risk of developing kidney stones and kidney injury [51]. Chronic kidney injuries are increasingly occurring in agricultural workers in low- and middle-income countries, likely associated with occupational heat stress exposure. In addition, heat can exacerbate underlying medical conditions, with a recent study showing that for those who already have end-stage renal disease, extreme heat exposure increases the risk of same-day hospital admission and mortality [52].

3.3.4 Mental health

The mental health impacts of heat exposure include increased depression and anxiety, violence, and post-traumatic stress disorder after climate-fueled natural disasters [53]. There is a higher rate of suicide associated with extreme heat, with one study finding that during periods of 1°C increase over the average monthly temperatures, suicide rates increased by 0.7% in the United States and by 2.1% in Mexico [54]. Elevated temperatures have also been shown to increase rates of interpersonal and intergroup violence, which can result in increased trauma both to oneself and to others [55]. In addition, heat exposure can negatively impact cognitive function and sleep quality [56, 57].

The most vulnerable include people with underlying mental health conditions, women who are pregnant (especially postpartum women), children, migrants and refugees, those of low socioeconomic status, and the elderly [44]. In addition, first responders to climate-related natural disasters also experience significantly higher rates of adverse psychological effects [58].

3.3.5 Allergies and respiratory health

Air pollution is a well-studied risk to respiratory health [59]. Those with underlying health conditions, such as chronic obstructive pulmonary disease and asthma, are most at risk, as well as those populations who are exposed to levels higher than recommended by the WHO. Air pollutants, from particulate matter to ozone, cause both acute inflammation and chronic lung changes, with health consequences of worsening asthma exacerbations, lung remodeling, and increased risk of lung cancer.

In addition, warming temperatures, changing precipitation patterns, and higher atmospheric carbon dioxide levels impact allergic respiratory diseases and asthma [60]. Climate change alters pollen allergies by affecting where plants and trees are able to grow, how long their season of growth is, and how much pollen there is in the atmosphere. In North America, the environmental allergy season is approximately 20% longer than 30 years ago, with about 21% more pollen in the air [61].

3.3.6 Infectious diseases

Warmer temperatures and changing precipitation patterns have widespread consequences on the spread and transmissibility of different types of infectious diseases, most notably vector-transmitted diseases [62]. For example, climate impacts can alter the geographical range for diseases such as malaria and dengue while contributing to an expanded range for certain vector-borne diseases, such as Zika virus [63]. Changes in sea surface temperature and salinity due to climate change have increased the suitability of conditions for Vibrio bacteria in certain regions, which can cause gastroenteritis, life-threatening cholera, and sepsis [31]. In addition, climate-related disasters, such as increased flooding and worsening drought, also increase the risk of water-borne infectious diseases such as cryptosporidium [64].

3.3.7 Pregnancy risks

Pregnant women are considered one of the most vulnerable populations to the impacts of global warming and air pollution, with risks both to the mother and to the infant [65]. An extensive systematic review published in 2020 showed that pregnant women exposed to elevated levels of ozone or fine particulate matter had an increased risk of preterm birth in 79% of studies and low birth weight babies in 86% of studies [66]. These risks were highest in minority groups, especially black mothers. In addition, women living in neighborhoods near polluting facilities and highways, most commonly found in low-income areas and communities of color, are at higher risk due to the higher level of air pollutants [24].

3.3.8 Food and water security

Food insecurity is increasing globally, affecting two billion people in 2019 [34]. Climate change threatens to exacerbate this global crisis, with rising temperatures shortening the time for crops to reach maturity, leading to reduced seed yield potential and further straining food systems worldwide. Reductions in time to maturity are observed in many staple crops, including maize, winter wheat, soybean, and rice. Worldwide, women play a key role in food security, and these climate-related changes pose an increased risk, especially for rural women and those in low-income global communities.

3.3.9 Disruptions to care

Climate change contributes to an increased frequency and intensity of many types of natural disasters, from wildfires to hurricanes to flooding. These intensified natural disasters pose a risk to healthcare delivery by disrupting access to medical care for those in need and potentially disrupting the healthcare facility’s infrastructure [67]. In addition, in the wake of a climate disaster, healthcare facilities globally are vulnerable to disruptions in power and service, with needs from electricity to waste disposal to access to food service delivery at risk [68].

4. Localized case studies and mental health impacts

4.1 Hurricane Sandy

On October 29th 2012, New York and New Jersey were slammed with a superstorm that had been brewing and inflicting damage on various coastal areas for the past few days, Hurricane Sandy. The two states were confronted with high winds with upwards of 80 mph and a barrage of rainfall and flooding, reaching heights of over 13 feet [69]. At Bellevue Hospital in New York following the storm, the hospital evacuated high-risk patients, however, it attempted to keep running on a generator before it became clear after roughly a day, that the damage to essential resources, such as water tanks, was more extensive than initially realized [70]. There was no choice but to evacuate the remaining patients to various available hospitals in better conditions nearby. Therefore, a total of 500 patients needed to be transferred from the hospital [71].

Flooding and power outages presented a set of unique issues for psychiatric patients in the aftermath of Hurricane Sandy at Bellevue and for several psychiatrists working in hospitals or the communities in the greater affected regions of New York and New Jersey. For example, psychiatry residents were recruited to assist by serving as couriers of food, medicine, and fuel up several flights of stairs and by moving discharged patients out of Bellevue. Outside of New York, Dr. Charles Ciolino, a psychiatrist and chair of the New Jersey Psychiatric Association’s Disaster Preparedness Committee, described the effects on psychiatric patients. This included an increase and exacerbation of anxiety disorders and addiction relapse, and the advent of problems such as coping with storm-related physical injuries, and difficulty obtaining psychotropic medications due to pharmacies also lacking power and experiencing flooding [72]. Not only were patients with pre-existing mental health disorders and those with psychotropic medicational needs adversely impacted, but other vulnerable populations saw an increase in adverse mental health impacts. A study evaluating any correlations between power outages and mental health issues during Sandy found that power outages positively correlated to mental health issues such as mood disorders, substance abuse, psychosis, and suicide. Notably, the rates of incidence were higher in lower-wealth counties such as Bronx, Kings, and New York, counties which comparably to Manhattan, experienced a longer blackout period. For example, Queens County had a 1.5-fold increase in mental health emergency department visits for every blackout increase of 1 percent, with Bronx County having a nearly 8-fold increase. Furthermore, researchers concluded that Bronx County, known for having high populations of African-American, Hispanic, and low-wealth communities, experienced a shorter blackout period than Nassau County, with a majority European-American population, but had higher adverse mental health incidences [73].

4.2 Hurricane Katrina

Hurricane Sandy is often compared to Hurricane Katrina, a hurricane that caused similar if not worse destruction and adverse impacts. Occurring a few years prior, this superstorm is known for the immediate and long-term devastating effects it had on coastal Louisiana/Mississippi regions, such as New Orleans. Like Sandy, the high winds and heavy rains brought by Hurricane Katrina caused widespread flooding, power outages, property damage, physical injuries, and death. Several people noted a disturbingly lackluster response by the federal government, including the then-mayor, Ray Nagin, who was convinced the poor response was due to racism and classism [74], considering 67% of the population of New Orleans was Black and of low socioeconomic status [75]. Therefore, some lacked the financial resources to evacuate. As a result, several citizens who were present during the storm experienced traumatic situations, such as Nia Burnett, a Black woman who was a young girl when she experienced Katrina. She recalled herself and her family attempting to take shelter at a nearby hospital, only to see corpses in bags lining the walls and the smell of dead bodies. Over a decade later, Burnett was diagnosed with post-traumatic stress disorder [76].

One risk factor for developing PTSD and other stress-related psychological disorders in the aftermath of a natural disaster is the existence of significant stressors or experiences with a previous traumatic event. Therefore, findings of studies show that ethnic minorities experience higher rates of PTSD: African Americans with rates higher than European Americans, and Hispanic/Latino Americans with the highest rates of PTSD [77]. This finding together with the previous is likely demonstrated by the daily and often compounded chronic stressors ethnic/cultural minorities and those of low economic status may experience such as racial discrimination, prejudice, family caretaking, and job strain [78].

4.3 Farmworkers and wildfires

In late Spring of 2023 in Canada, the first wildfire of the season started what would be unprecedented and have widespread effects with hundreds of fires; many reaching “megafires” status due to increasing to sizes of 39 square miles [79]. The negative health effects of wildfire smoke are known including respiratory, cardiovascular, and even neuro-cognitive, in addition to indirect mental health impacts. Unsurprisingly, those most at-risk are ethnic minorities and those of low socioeconomic status [80]. In particular, one group is farmworkers. This group of outdoor workers is often comprised of those who are ethnic minorities, of low socioeconomic status, and additionally have difficulties of limited educational proficiency [81]. Therefore, when the Canadian wildfires began to rage, farmworkers were one of the most intersectionality at-risk groups to be negatively impacted.

The mental health of farmworkers in general has been well documented, with research and advocacy addressing and evaluating the harmful conditions the vast majority of farmworkers are forced to work in. One example is exposure to pesticides. In a survey, participants who worked near Lake Apopka in 2006, reported experiencing “sadness a lot” at 38%, “nervousness for no apparent reason” at 42%, and “uncontrollable anger” at 37% [82]. Therefore, the social disadvantages and poor working conditions with the added impact of wildfires and the subsequent smoke, together with the trauma of experiencing wildfires, can lead to the development of mood disorders, such as major depressive disorder and generalized anxiety disorder, or stress-related disorders such as post-traumatic stress disorder.

5. Government and healthcare policy

Climate change is a global phenomenon that has far-reaching implications for public health. With the goal of achieving environmental justice, almost a decade later, President Bill Clinton signed the Environmental Justice Executive Order in 1994. This effort to focus Federal attention on the environmental and human health effects in low-wealth and minority communities aimed to achieve environmental justice.

The US Department of Health and Human Services (HHS) has identified climate change as a significant threat to human health, particularly for vulnerable populations [83]. The HHS Office of Climate Change and Health Equity (OCCHE) has been established to address the health impacts of climate change and promote health equity [83].

To address the health impacts of climate change, healthcare policies must prioritize health equity and ensure that vulnerable populations have access to the resources they need to adapt to the changing climate. The OCCHE has developed a referral guide summarizing resources that can address patients’ social determinants of health and mitigate health harms related to climate change [84]. The guide provides information on how to identify patients who may be at risk for climate-related health impacts and how to connect them with resources that can help [84].

In addition, the HHS has developed a Climate and Health Literacy Initiative to promote climate and health literacy among healthcare professionals and the public [83]. The initiative aims to increase awareness of the health impacts of climate change and provide healthcare professionals with the tools they need to address these impacts [83].

The Inflation Reduction Act (2022) invests billions of US dollars in climate solutions and environmental justice and is the most substantial US climate health policy to date. It is intended to build on the Bipartisan Infrastructure Law and the Justice 40 Initiative which aims to invest 40 percent of the overall benefits of climate and clean energy investments to disadvantaged communities such as low-income communities, communities of color and Tribal and Indigenous communities [84, 85]. The Act aims to reduce pollution, improve clean transit, make clean energy more affordable and accessible, and strengthen resilience to climate change via climate and environmental Justice block grants, funding for monitoring, investments at public schools in disadvantaged communities, addressing diesel emission, creating neighborhood access and equity grants, cleaning up ports, increasing solar project development, creating a clean energy and sustainability accelerator and improving the climate resilience of affordable housing. This bill is a significant step forward for US climate action and is the largest investment to address global warming in US history.

The Justice40 initiative directs federal agencies to deliver 40 percent of the climate, clean energy, affordable and sustainable housing, clean water and additional investments to disadvantaged communities. The investment represents billions of US dollars in annual investments from hundreds of federal programs being utilized to maximize the benefits to disadvantaged communities and includes programs funded or created in the President’s Bipartisan Infrastructure Law. There are 13 programs at HHS covered under the Justice40 initiative including programs under the National Institutes of Health, Centers for Disease Control and the Administration for Children and Families [86, 87].

6. Healthcare systems and intersection with climate change

The healthcare industry is responsible for significant greenhouse gas emissions, which contribute to climate change. According to the American Association of Medical Colleges, the global healthcare industry is responsible for two gigatons of carbon dioxide yearly, or 4.4% of worldwide net emissions [88]. In the United States, the healthcare system is responsible for 8.5% of total greenhouse gas emissions [89]. Additionally, the indirect public health harms from greenhouse gas and additional pollutant emissions from the healthcare sector were estimated to result in the loss of 388,000 disability-adjusted life-years and provide similar health harms as that of medical errors [7].

Globally, the US healthcare emissions are the highest per capita, representing 27% of the global healthcare climate footprint [86]. The majority of healthcare emissions are indirect, or Scope 3 emissions mainly represented by the supply chain, including food, pharmaceuticals, supplies, and devices [7].

Hospitals have the highest energy intensity of all publicly funded buildings and emit 2.5 times more greenhouse gases than commercial buildings [90]. Therefore, switching to renewable energy can have a significant impact. Hospitals can also reduce their carbon footprint by improving energy efficiency, reducing waste, and using environmentally friendly products [91].

7. Interventions and initiatives for adaptation and mitigation

Climate change is real, affects the entire global community, and disproportionately impacts those considered vulnerable populations [92]. Structural changes to mitigate its effects should be aimed at understanding this basic acknowledgment toward ensuring environmental sustainability. This is where understanding climate change and furthering health equity intersect. There is no full realization of the impacts of climate change on communities without incorporating the need for equitable solutions to decrease the impacts of air pollution, fossil fuel emissions, lack of sustainable agriculture, increased flooding, inadequate plumbing and waste management, severe weather events, and heat-related illness as examples on Black Indigenous People of Color (BIPOC) and other disparately impacted groups. Everyone is at risk of the impacts of climate change, but communities of people who often experience the brunt of it lack resources to respond to it and protect themselves from it. Climate change is not a political issue. It is a substantive issue and, ergo, takes real solutions.

7.1 Adaptation and mitigation measures

Adaptation is the response to climate change that is already taking place. Mitigation is the active process of decreasing and eventually stopping the amount of greenhouse gases already in the atmosphere that cause global warming and are linked to further carbonization of the environment [93]. Adaptable and mitigating measures take place at the individual and community levels to lessen climate change and its effects, and there are actions that individual neighborhoods, households, and municipalities can take. Examples of climate adaptation include planting trees (e.g., arborization) to create cooler homes and neighborhoods, decreasing the risk of fire hazards by clearing brush, and purchasing insurance to be prepared for damage from and to rebuild after natural disasters [94]. With these efforts, priority should be focused on the most vulnerable communities, with estimated costs projected to be $300 billion by 2030 to help developing countries become more adaptable to climate change. Climate mitigation includes identifying more renewable energy sources and relying less on greenhouse gas emissions and their sources, including power plants, factories, cars, and even farms. Halting deforestation and achieving proper land use will help reach the goal of global climate neutrality by 2050, per the European Environmental Agency [95].

7.2 Advocacy and academic initiatives in the health profession

Those committed to climate advocacy are needed to both influence action and educate the general public about the implications of climate change on the global community, but missing in much of the published discourse is an increased need for physicians of color to minister to the climate change education needs of vulnerable populations, especially BIPOC communities. Physicians of color and their relationships with their patients represent an essential utility in educating those at most significant risk of the effects of climate change and the lack of environmental sustainability on health. Organizations such as the Medical Society Consortium on Climate and Health (MSCCH) and its Climate and Health Equity Fellowship (CHEF) provide intensive training for physicians of color from disparate specialties and lead the way in these efforts. Additional affiliate organizations, such as state-specific clinician advocacy groups to promote climate change education and awareness are also involved in these efforts, as the trust that patients have in their physicians is of utmost importance to ensure the viability of such initiatives. Broadening physician understanding of how climate impacts health while providing physicians with the expertise to be advocates for policy change to lessen the impacts of climate change on health is necessary. Structural changes in medical practices and healthcare delivery systems are also crucial to increasing patient education on climate change and its impacts on health [96]. Involving physicians in meetings with legislators who make policy that impacts populations and altering medical curricula by oversight bodies such as the Accreditation Council on Graduate Medical Education and the Liaison Committee on Medical Education to improve education of medical students and physicians in training, as is being done at institutions like George Washington University’s School of Medicine, are crucial to the education of a generation of clinicians who will have, further cultivate, and maintain the expertise to help populations of patients learn more about how to protect themselves from climate change [97]. Medical curricular improvements must include, toward the achievement of health equity, an understanding of how climate change overlaps with the social determinants of health, disability studies, and structural racism [98].

8. Call to action

The passage of landmark legislation such as the Inflation Reduction Act (IRA) of 2022 and the Infrastructure and Investment in Jobs Act (IIJA) of 2021 happened in the United States under the Biden administration because of an important recognition that we are living in a world where larger, wealthier countries are emitting greenhouse gases more than smaller, less industrialized nations and action is necessary to change this [85, 86]. As can be understood, climate change is a multifactorial woe and, therefore, will require a multifactorial, multi-faceted approach to stopping it. Each of us has a crucial role in decarbonizing our environment and improving our lives by ensuring the sustainability and longevity of our planet. Together, we can achieve the goal of keeping the planet’s warming to less than 2 degrees Celsius [99].

As an example, power plants can switch to renewable energy options in producing cars and, in so doing, produce more and eventually only electric vehicles. Individuals, families, and businesses can purchase electric vehicles as their only mode of transportation. State and local governments can purchase those electric vehicles in the form of school busses to transport students to school. Physicians can be trained to educate patients at the point of care about how such a process lessens air pollution, reduces greenhouse gas emissions, and diminishes the burden of new-onset asthma development, increased mental illness caused by severe weather events, and heat-related illness. Legislators at the local, state, and national levels can write and pass legislation to provide tax credits to households, individuals, and businesses who purchase those electric vehicles and support physicians via reimbursement measures through health insurance who educate their patients consummately on the impacts of climate change.

This is just one example of how to employ the interdependence of all facets of society to help transform current practices and policies toward the end of stopping climate change. This example also demonstrates that though there are multiple players involved in the fight to end climate change, the individual community needs are at the center of combating climate change and its effects, and the voice of the individual community must be honored, prioritized, and respected in order for any framework to be successful [100]. We all have a role, and each role is important. Become an advocate. Join a group devoted to speaking out and effecting policy against climate change. Run for office with climate change action as a significant component of your platform. Become more educated on the ravages of climate change on the global community and especially vulnerable populations. Learn how you can sustainably green your environment, home, and business. Realize that climate change is real, as that is where this entire process starts. Your voice matters in the global fight to save all lives and protect our planet for future generations.

9. Conclusion

Climate change and environmental justice have a significant impact on health and healthcare. The intricate interplay between climate change, environmental justice, and healthcare constitutes a multifaceted challenge reverberating across global landscapes. The vectors of climate change via exposure pathways impact the health of all populations. However, historical, political, environmental, structural, and social factors interact so that all populations are not equally affected and disproportionately burdened. The healthcare sector must employ initiatives to mitigate and adapt to counteract the impact of climate change.

Acknowledgments

The authors would like to acknowledge the contribution of Dr. Neelima Tummala to this manuscript.