There is one common health objective among all nations, as stated in the constitution of the World Health Organization in 1947: progress towards the best feasible level of health for all people. This goal captures the concept of health equity: fair distribution of unequal health. However, 70 years later, this common global objective has never been measured. Most of the available literature focuses on measuring health inequalities, not inequities, and compare health indicators (mainly access to health services) among population subgroups. A method is hereby proposed to identify standards for the best feasible levels of health through criteria of healthy, replicable, and sustainable (HRS) models. Once the HRS model countries were identified, adjusted mortality rates were applied to age- and sex-specific populations from 1950 to 2015, by calculating the net difference between the observed and expected mortality, using the HRS countries as the standard. This difference in mortality represents the net burden of health inequity (NBHiE), measured in avoidable deaths. This burden is due to global health inequity, that is, unfair inequality, due to social injustice. We then calculated the relative burden of health inequity (RBHiE), which is the proportion of NBHiE compared with all deaths. The analysis identified some 17 million avoidable deaths annually, representing around one-third of all deaths during the 2010–2015 period. This avoidable death toll (NBHiE) and proportion (RBHiE) have not changed much since the 1970s. Younger age groups and women are affected the most. When data were analyzed using smaller sample units (such as provinces, states, counties, or municipalities) in some countries, the sensitivity was increased and could detect higher levels of burden of health inequity. Most of the burden of health inequity takes place in countries with levels of income per capita below the average of the HRS countries, which we call the “dignity threshold.” Based on this threshold, a distribution of the world’s resources compatible with the universal right to health—the “equity curve”—is estimated. The equity curve would hypothetically be between this dignity threshold and a symmetric upper threshold around the world’s average per capita GDP. Such excess income prevents equitable distribution is correlated with a carbon footprint leading to >1.5º global warming (thus undermining the health of coming generations), and does not translate to better health or well-being. This upper threshold is defined as the “excess accumulation threshold.” The international redistribution required to enable all nations to have at least an average per capita income above the dignity threshold would be around 8% of the global GDP, much higher than the present levels of international cooperation. At subnational levels, the burden of health inequity can be the most sensitive barometer of socioeconomic justice between territories and their populations, informing and directing fiscal and territorial equity schemes and enabling all people within and between nations to enjoy the universal right to health. HRS models can also inspire lifestyles, and political and economic frameworks of ethical well-being, without undermining the rights of others in present and future generations.
Juan Garay, David Chiriboga, Nefer Kelley, and Adam Garay
R. Quentin Grafton, Long Chu, and Paul Wyrwoll
Water insecurity poses threats to both human welfare and ecological systems. Global water abstractions (extractions) have increased threefold over the period 1960–2010, and an increasing trend in abstractions is expected to continue. Rising water use is placing significant pressure on water resources, leading to depletion of surface and underground water systems, and exposing up to 4 billion people to high levels of seasonal or persistent water insecurity. Climate change is deepening the risks of water scarcity by increasing rainfall variability. By the 2050s, the water–climate change challenge could cause an additional 620 million people to live with chronic water shortage and increase by 75% the proportion of cropland exposed to drought. While there is no single solution to water scarcity or water justice, increasing the benefits of water use through better planning and incentives can help. Pricing is an effective tool to regulate water consumption for irrigation, for residential uses, and especially in response to droughts. For a water allocation to be efficient, the water price paid by users should be equal to the marginal economic cost of water supply. Accounting for all costs of supply is important even though, in practice, water prices are typically set to meet a range of social and political objectives. Dynamic water pricing provides a tool for increasing allocative efficiency in short-term water allocation and the long-term planning of water resources. A dynamic relationship exists between water consumption at a point in time and water scarcity in the future. Thus, dynamic water pricing schemes may take into account the benefit of consuming water at that time and also the water availability that could be used should a drought occur in the future. Dynamic water pricing can be applied with the risk-adjusted user cost (RAUC), which measures the risk impact of current water consumption on the welfare of future water users.
Junfeng Yu, Lianping Yang, Hung Chak Ho, and Cunrui Huang
Climate change has resulted in rising global average temperatures and an increase in the frequency and intensity of extreme weather events, which already has and will yield serious public health consequences, including the risk of diarrheal diseases. Sufficient evidence in the literature has highlighted the association between different meteorological variables and diarrhea incidence. Both low and high temperatures can increase the incidence of diarrheal disease, and heavy rainfall has also been associated with increased diarrhea cases. Extreme precipitation events and floods are often followed by diarrhea outbreaks. Research has also concluded that drought can concentrate pathogens in water sources, which makes it possible for diarrhea pathogens to distribute broadly when the first heavy rain happens. Substantial evidence underscores the important role social, behavioral, and environmental factors may have for the climate-diarrhea relationship. Meteorological factors may further influence the social vulnerability of populations to diarrhea through a variety of social and behavioral factors. Future research should focus on social factors, population vulnerability, and further understanding of how climate change affects diarrhea to contribute to the development of targeted adaptation strategies.
Sonia Akter and Shaleen Khanal
The link between risk perception and risk response is not straightforward. There are several individual, community, and national factors that determine how climate change risk is perceived and how much of the perception translates to response. The nexus between risk perception and risk response in the context of water resource management at the individual, household, community, and institutional level has been subject of a large body of theoretical and empirical studies from around the globe. At the individual level, vulnerability, exposure, and cognitive factors are important determinants of climate change risk perception and response. At the community level, risk perception is determined by culture, social pressure, and group identity. Responses to risk vary depending on the level of social cohesion and collective action. At the national level, public support is a key determinant of institutional response to climate change, particularly for democratic nations. The level of global cooperation and major polluting countries’ willingness to curb their fair share of greenhouse gas emissions also deeply influence policymakers’ decisions to respond to climate change risk.
Barry S. Levy and Cora Roelofs
Climate change has increased the risk to workers’ health and safety. Workers, especially those who work outdoors or in hot indoor environments, are at increased risk of heat stress and other heat-related disorders, occupational injuries, and reduced productivity at work. A variety of approaches have been developed to measure and assess workers’ occupational heat exposure and the risk of heat-related disorders. In addition, increased ambient temperature may increase workers’ exposure to hazardous chemicals and the adverse effects of chemicals on their health. Global warming will influence the distribution of weeds, insect pests, and pathogens, and will introduce new pests, all of which could change the types and amounts of pesticides used, thereby affecting the health of agricultural workers and others. Increased ambient temperatures may contribute to chronic kidney disease of unknown etiology among workers. Global warming is increasing ground-level ozone concentrations with adverse effects on outdoor workers and others. Extreme weather events related to climate change pose injury risks to rescue and recovery workers. Reducing the risks of work-related illnesses and injuries from climate change requires a three-pronged approach: (1) mitigating the production of greenhouse gases, the primary cause of climate change; (2) implementing adaptation measures to address the overall consequences of climate change; and (3) implementing improved measures for occupational health and safety.
Nu Quy Linh Tran, Des Connell, Trung Hieu Nguyen, and Dung Phung
The Mekong Delta Region (MDR) in Vietnam, located at the downstream end of the Mekong River, is highly affected by climate change and extreme weather events, such as floods, droughts, soil erosion, and salinization. Due to the specific characteristics of climate, topography, river systems, and population, water-related diseases (WRDs) have been a disease burden in the Mekong Delta. This article aims to critically review the evidence of existing studies on the association between climatic conditions and WRDs in the MDR. Dengue was found to be most sensitive to the changes in ambient temperatures, humidity, and rainfall at a lag of 2 months. The climate-based prediction model was recommended for an early warning system to enhance dengue prevention. Diarrheal diseases are highly correlated with extreme weather events such as high temperatures and floods, but the evidence on the association between climatic conditions and cause-specific WRDs is limited and inconclusive. Despite the preliminary evidence for the development of climate change adaptation strategies in the MDR, studies on other WRDs (i.e., water-washed, water-scarce, and water-contaminated diseases) should be conducted. In addition, future studies should investigate the effects of interaction between climatic factors and sociodemographic, household, and individual factors in predicting climate-sensitive diseases. How to translate and integrate the scientific evidence to the policy and practices that protect the MDR residents from the elevated extreme weather events due to climate change should be warranted.
Luiz Augusto Cassanha Galvao, Volney Câmara, and Daniel Buss
The relationship between environment and health is part of the history of medicine and has always been important to any study of human health and to public-health interventions. In Latin America many health improvements are related to environmental interventions, such as the provision of better water and sanitation services. Latin America’s development, industrialization, and sweeping urbanization have brought many improvements to the well-being of its populations; they have also inaugurated new societies, with new patterns of consumption. The region’s basic environmental-health interventions have needed to be updated and upgraded to include disciplines such as toxicology, environmental epidemiology, environmental engineering, and many others. Multidisciplinary and inter-sector approaches are paramount to understanding new profiles of health and well-being, and to promoting effective public-health interventions. The new social, economic, labor, and consumption aspects of modern Latin American society have become more and more relevant to understanding the complex interactions in the region’s social, biological, and physical environment, which are essential to explaining some of the emerging and re-emerging public-health problems. Environmental health, as concept and as intervention, is simple and easily understood, but no longer sufficient to achieve the levels of health and well-being expected and required by these new realities. Many global changes such as climate change, biodiversity loss, and mass migrations has been identified as main cause of ill health and are at the center of the sustainable development challenges in general, and many are critical and specific public health. To face this development, other frameworks have emerged, such as planetary health and environmental and social determinants of health. Public health remains central to some, such as the improved environmental-health agenda, while others assign public health a relative position in a variety of overarching frameworks.
Irena Gorski and Brian S. Schwartz
Unconventional natural gas development (UNGD), which includes the processes of horizontal drilling and hydraulic fracturing to extract natural gas from unconventional reservoirs such as shale, has dramatically expanded since 2000. In parallel, concern over environmental and community impacts has increased along with the threats they pose for health. Shale gas reservoirs are present on all continents, but only a small proportion of global reserves has been extracted through 2016. Natural gas production from UNGD is highest in the United States in Pennsylvania, Texas, Louisiana, Oklahoma, and Arkansas. But unconventional production is also in practice elsewhere, including in eighteen other U.S. states, Canada, and China. Given the rapid development of the industry coupled with its likelihood of further growth and public concern about potential cumulative and long-term environmental and health impacts, it is important to review what is currently known about these topics. The environmental impacts from UNGD include chemical, physical, and psychosocial hazards as well as more general community impacts. Chemical hazards commonly include detection of chemical odors; volatile organic compounds (including BTEX chemicals [benzene, toluene, ethylbenzene, and xylene], and several that have been implicated in endocrine disruption) in air, soil, and surface and groundwater; particulate matter, ozone, and oxides of nitrogen (NOx) in air; and inorganic compounds, including heavy metals, in soil and water, particularly near wastewater disposal sites. Physical hazards include noise, light, vibration, and ionizing radiation (including technologically enhanced naturally occurring radioactive materials [TENORMs] in air and water), which can affect health directly or through stress pathways. Psychosocial hazards can also operate through stress pathways and include exposure to increases in traffic accidents, heavy truck traffic, transient workforces, rapid industrialization of previously rural areas, increased crime rates, and changes in employment opportunities as well as land and home values. In addition, the deep-well injection of wastewater from UNGD has been associated with increased seismic activity. These environmental and community impacts have generated considerable concern about potential health effects and corresponding political debate over whether UNGD should be promoted, regulated, or banned. For several years after the expansion of the industry, there were no well-designed, population-based studies that objectively measured UNGD activity or associated exposures in relation to health outcomes. This delay is inherent after the introduction of new industries, but hundreds of thousands of wells were drilled before any health studies were completed. By 2017, there were a number of important, peer-reviewed studies published in the scientific literature that raised concern about potential ongoing health impacts. These studies have reported associations between proximity to UNGD and pregnancy and birth outcomes; migraine headache, chronic rhinosinusitis, severe fatigue, and other symptoms; asthma exacerbations; and psychological and stress-related concerns. Beyond its direct health impacts, UNGD may be substantially contributing to climate change (due to fugitive emissions of methane, a powerful greenhouse gas), which has further health impacts. Certain health outcomes, such as cancer and neurodegenerative diseases, cannot yet be studied because insufficient time has passed in most regions since the expansion of UNGD to allow for latency considerations. With the potential for tens of thousands of additional wells across large geographic areas, these early health studies should give pause about whether and how UNGD should proceed. Citing health concerns, several U.S. states and nations in Europe have already decided to not allow UNGD.