Air Pollution – WMA – The World Medical Association

Adopted by the 75^th WMA General Assembly, Helsinki, Finland, October 2024

PREAMBLE

The impact of air pollution on health – especially among vulnerable populations – necessitates targeted guidelines for healthcare professionals. By recognizing air pollution’s unique characteristics, this declaration aims to advocate for better health, foster cross-border collaboration, and reinforce the connection between environmental quality and human well-being.

Air pollution and its impact on health

Air pollution poses a major global environmental risk to human health, contributing significantly to avoidable morbidity and mortality worldwide. 8.1 million premature deaths occur each year due to the combined effects of ambient and household air pollution.

Air pollutants are a leading risk factor for the burden of non-communicable diseases, leading to stroke, myocardial infarctions, lung cancer as well as chronic respiratory illnesses. It also increases the risk of childhood asthma and asthma severity.

Air pollutants are a diverse range of harmful substances that contaminate the air we breathe. These include gases such as sulphur dioxide, nitrogen oxides, carbon monoxide, methane, and volatile organic compounds, as well as particulate matter like smoke, soot (black carbon), and fine dust.

In 2022, WHO estimated that 99% of the global population was exposed to air pollution concentrations that exceeded WHO’s air quality limits.

While no region of the world has been spared, low and middle-income countries bear the largest burden of premature mortality associated with air pollution.

Without implementation of aggressive interventions, the number of premature deaths caused by ambient air pollution is projected to rise by over 50% by the year 2050.

The sources of air pollution

Fossil fuel combustion, petrol- and diesel-powered vehicle emissions have been highlighted as the major contributor to air pollution-related mortalities, particularly in urban areas.

Diesel soot is a proven carcinogen with toxic effects on cardiovascular and respiratory systems.

Household air pollution, caused largely by open cooking fires and inefficient stoves, is a leading risk factor for childhood mortality, contributing to approximately 50% of deaths from acute lower respiratory infections, including pneumonia, in children under the age of five.

Beyond traditional airborne pollutants, biological air pollution – airborne pathogens such as bacteria, viruses, and fungi, particularly indoors – has gained attention.

Infected individuals can contribute to such air contamination, emphasizing the need for appropriate prevention strategies and comprehensive air quality control.

Plastics contribute to air pollution directly through its open-air combustion and through microplastics carried by wind and air currents.

RECOMMENDATIONS

The WMA acknowledges the severity of consequences stemming from air pollution and urges the following stakeholders to promptly take action to achieve clean air:

The WMA and its constituent members should:

Engage with local, regional, and national authorities to raise public awareness about the health impacts of air pollution and the importance of its prevention.
Work together with governments to develop and implement strategies to improve air quality, as identified in the WHO air quality guidelines, and mitigate the effects of air pollution. These strategies should consider the local context and reflect the latest scientific evidence.
Advocate for and support the integration of health impacts of air pollution and its solutions into medical curricula and professional educational programs, fostering a comprehensive understanding and proactive approach among healthcare professionals.
Encourage collaboration between organised medicine and other stakeholders, including government agencies and international organizations, to develop best practices for minimising greenhouse gas emissions and plastic use in healthcare settings.

The WMA urges governments to:

Recognise that air pollution negatively impacts human health and environmental sustainability and that existing health inequities exacerbate susceptibility to environmental hazards.
Recognise the important role of social and environmental determinants of health and strive to include these in policy-making processes, for example by conduction of health equity impact assessments.
Allocate resources and funding for reducing and monitoring air quality and implement effective pollution prevention and control measures, particularly in densely populated areas, in line with WHO’s air quality standards.
Enhance early warning systems for anticipated poor air quality periods and prepare health systems to handle air pollution-related health impacts effectively.
Implement measures that improve air quality, such as increasing access to clean energy and creating green spaces.
Take measures toward sustainable healthy transport by implementing strategies to decarbonise the transportation sector, such as enforcing stricter vehicle emission standards, promoting public transportation and implementing cycling and walking infrastructure.
Invest in and support research and innovation for cleaner healthcare sector technologies and practices.
Establish guidelines and standards for acceptable levels of biological contaminants in indoor air, including policies to reach those objectives such as by ensuring adequate ventilation and air filtration.
Strive towards good environmental governance by developing sustainable strategies, policies, and measures to address environmental hazards and take a precautionary principle approach to protect health.

The WMA recommends that international and intergovernmental agencies:

Recognize and promote access to clean, breathable air free from harmful pollutants as a basic human right for all people worldwide.
Work with governments to update public health policies, prioritize air pollution control and strengthen efforts in health promotion and pollution reduction.
Advocate for the maximum reduction of all sources of air pollution, recognising that it is critical for sustainability that anthropogenic (human) activities operate within the safe limits of the Earth’s ecosystem.
Promote and support governments in conducting health impact assessments across relevant policy sectors, empowering them to proactively reduce exposure to air pollution and safeguard public health.

The WMA urges individual physicians to:

Stay informed regarding health effects of air pollution.
Consider air pollution as a potential environmental risk factor in relevant patient consultations and where relevant, promote lifestyle modifications and preventive measures that minimize exposure to pollutants.

Adopted by the 71^st WMA General Assembly (online), Cordoba, Spain, October 2020

PREAMBLE

Exponential increase in the number of climate change related fires, hurricanes, ice meltdowns, heat waves and deforestation, especially of the rainforests, show that there is no time to waste. There is an urgent need to accelerate the efforts that will trigger the changes to be implemented by international and national policy and decision makers in order to stop as well as to adapt to the climate crisis.

Climate change and air pollution are closely connected, both have huge impacts on human health and result from anthropogenic emissions due to the combustion of fossil fuels. As it is mentioned by international bodies such as Clean Air Initiative founded by the UN, the World Health Organization (WHO), the UN Environment Programme (UNEP) and the Climate and Clean Air Coalition (CCAC); all governments, researchers and non-governmental organisations should urgently start to tackle the air pollution and climate crisis together.

Considering the urgency and complexity of climate change, it is needed to create a global change to stop the causes of this crisis. Therefore, WMA calls on international, national, regional or provincial decision makers such as politicians, policy makers and judges to recognize the urgency, complexity, and interconnectedness of the essence of the climate crisis action and to take immediate action in order to protect the rights of future generations for the sake of climate justice.

Climate crisis causes a serious loss, damage or destruction of ecosystems and cultural damage, which has severe impacts on all inhabitants of the world. In order to ensure the right to live for the future generations, there is an imminent need for binding legal measures to be adopted and implemented at the national and international arena against the polluters causing emissions that cause especially climate crisis as well as air, water and soil pollution.

Health professionals have a duty to care, respect and protect the human life, as well as the right to live for future generations and all forms of the natural living world. WMA believes that all people, including future generations, have the right to the environmental, economic and social resources needed for healthy and productive lives; such as clean air, soil, water and food security. Therefore; WMA has a historical responsibility of acting proactively in order to initiate the necessary changes and solutions to struggle with the climate crisis.

RECOMMENDATIONS

WMA proposes the following recommendations to its members and other related organizations:

Urge to ask its members to collaborate with relevant bodies in their countries in order to raise awareness about the necessity for legally binding sanctions and policies at the national and international level for the polluters that threaten the right to live for the future generations by emitting gases which are proven to cause climate crisis and air, soil and water pollution.
Urge all national governments, policy makers, researchers and health professionals to mobilize in order to develop and implement comprehensive policies to struggle with the problems due to the use of fossil fuels by industry as well as the individuals that lead to problems such as climate crisis air, water and soil pollution.
Urge all medical professionals, media, governmental and non – governmental institutions to refer climate change as ‘climate crisis’ and calls the leaders of national, state or provincial, regional, city, and local governments to declare a climate emergency in order to initiate a society-wide action. Moreover, encourage the media to promote the concept and meaning of the right to live for future generations.
Update the curriculum at medical schools and add compulsory sections on environmental health in order to educate health professionals that are able to think critically about the health impacts of the environmental problems, are aware of the reasons, impacts/dimensions of the climate crisis and able to offer solutions designed to protect the rights and health of future generations.
Advocate and organize interdisiplinary campaigns in order to stop the new permissions from being given to the industrial facilities using fossil fuels that cause climate crisis and pollution.
Urge national governments and international bodies such as WHO to adopt stricter regulations on environmental protection and evaluation, permission, monitoring and control procedures of new industrial facilities to limit the health impact resulting from their emissions.
Advocate actively for policies that will maximize health benefits by reducing air pollutants (such as ground ozone and particulate matter etc.) and carbon emissions, increase walking, cycling, and use of public transport, and consumption of nutritious, plant-rich diets to ensure climate justice. Urge international, national, state or provincial, regional, city, and local governments to adopt and implement air quality and climate change policies that will achieve the WHO Ambient Air Quality Guideline values.
Urge national, state or provincial, regional, city, and local governments through public campaigns and advocacy to cut subsidies given to fossil fuel industries and to direct these subsidies to support just transition, energy efficiency measures, green energy resources and public welfare.
Urge governments and private sector to invest in policies that support a just transition for workers and communities adversely impacted by the move to a low-carbon economy and to build social protection through investment in and transition to green jobs.
Urge national, state or provincial, regional, city, and local governments to act on other causes of climate crisis such as industrial agriculture, animal husbandry and deforestation, to promote legal trade and financing policies that prioritize and enable sustainable agro-ecological practices, end deforestation for the expansion of industrial agriculture and to reduce reliance on industrial animal-based agriculture and environmentally damaging agricultural and fisheries practices.
Urge national, state or provincial, regional, city, and local governments to invest in human capacity and knowledge infrastructure to spread regenerative agriculture solutions that can produce the change needed while providing myriad co-benefits to farmers and consumers, providing a global support network – on the ground – for farmers and capturing carbon in the soil. Emphasize building resilient and regenerative local food systems that can reduce carbon emissions, support the livelihoods of agricultural communities and provide food security for future generations.
Urge national governments, together with the involvement of health sector, to develop national adaptation plans and to conduct national assessments of climate crisis impacts, vulnerability, and adaptation for health.

Adopted by the 30th World Medical Assembly Sao Paulo, Brazil, October 1976
and revised by the 36th World Medical Assembly Singapore, October 1984
and rescinded at the WMA General Assembly, Santiago 2005

Preamble

The World Medical Association, having considered the problem of pollution at its Scientific Conference held in Sao Paulo in 1976, emphasizes the importance of the ecological balance between people and their surroundings and stresses that as countries undergo social and economical development they should take steps for the improvement of the quality of their environment.

The problem of pollution affects not only the viability and beauty of the environment, but constitutes a growing threat to the very health of the humans who occupy it. Thus physicians must play a major role in prevention of disease due to pollution.

Definition

Environmental pollution may be defined as the result of actions taken by people, either consciously or due to neglect or ignorance, that degrade or contaminate the natural environment. For example, the indiscriminate disposal of chemical wastes may lead to irreparable contamination of precious acquifers from which come water that is essential to human life.

Certain adverse physical factors, ionizing radiation and chemicals such as chromium, asbestos, and those in tobacco are associated with cancer and other fatal or disabling illnesses, including birth and developmental defects among the descendants of exposed persons. Controlling exposures to such factors would have a salutary effect on people’s health and survival. Therefore, high priority should be given to the elimination of adverse physical factors in the home, school, workplace, and elsewhere.

Microbiological and chemical agents may prominently and adversely affect the health of workers and of the general population. Micro-biological agents can cause communicable diseases, as is apparent from decades of recorded experience. Chemicals can cause non-communicable hazards. Persons who are involved with food production and distribution have the responsibility of minimizing consumers’ exposures, not only to harmful microbiological agents, but also to agricultural chemicals used to increase crop production and to unsafe additives that may be used to preserve foods.

Component of Problem

Among the specific contributors to the problem of pollution, the following may be mentioned:

Air pollution involving oxides of nitrogen, photochemical oxidents, hydrocarbons, sulfur dioxide, lead, and certain particulates in the ambient air. Such substances can cause adverse pathophysiologic effects in children and adults and can damage plants and property.
Water pollution due to discharge of improperly treated human sewage wastes, and of agricultural and industrial wastes, into bodies of water. Such discharges contaminate drinking water with viruses, bacteria and other infectious micro-organisms; inorganic and organic chemicals, and radio-active substances. Water pollution also results in the reduction of recreational opportunities and of commercial fishing resources.
Solid wastes that attract rodents and insects at disposal sites and degrade the air and water; wastes can release toxic materials into the environment.
Excessive sound levels produced by industrial sources, transportation systems, audio systems and other means, may lead to permanent hearing loss, other pathophysiologic effects, and emotional disturbances.

Responsibility of Physicians

Physicians have the responsibility to educate the public and to encourage the establishing and maintaining of programs of environmental protection for their communities.

Recommendation

Individual physicians and National Medical Associations should take appropriate action to discharge the foregoing responsibility.

Adopted by the 67^th WMA General Assembly, Taipei, Taiwan, October 2016

PREAMBLE

As noted by the 65th World Medical Assembly in Durban in 2014, physicians around the world are aware that fossil fuel air pollution reduces quality of life for millions of people worldwide, causing a substantial burden of disease, economic loss, and costs to health care systems.

According to World Health Organization data, in 2012, approximately “7 million people died, one in eight of total global deaths, as a result of air pollution” (WHO, 2014).

The United Nations’ Intergovernmental Panel on Climate Change (IPCC) notes that global economic and population growth, relying on an increased use of coal, continues to be the most important driver of increases in Carbon Dioxide emissions. These emissions are the major component of an accelerating the amount of human fossil fuel Greenhouse Gas (GHG) emissions despite the adoption of climate change mitigation policies (IPCC, 2014).

The burden of disease arising from Climate Change will be differentially distributed across the globe and, while it will affect everyone, the most marginal populations will be the most vulnerable to the impacts of climate change and have the least capacity for adaptation.

BACKGROUND

In many densely settled populated cities around the world, the fine dust measurable in the air is up to 50 times higher than the WHO recommendations. A high volume of transport, power generated from coal, and pollution caused by construction equipment are among the contributing factors (WMA, SMAC 197, Air Pollution WMA Statement on the Prevention of Air pollution due to Vehicle Emissions 2014).

Evidence from around the world shows that the effects of climate change and its extreme weather are having significant and sometimes devastating impacts on human health. Fourteen of the 15 warmest years on record have occurred in the first 15 years of this century (World Meteorological Organization 2014). The vulnerable among us including children, older adults, people with heart or lung disease, and people living in poverty are most at risk from these changes.

The WMA notes the Lancet Commission’s description of Climate Change as “the greatest threat to human health of the 21st century”, and that the Paris agreement at COP21 on Climate calls upon governments “when taking action on climate change” to “respect, promote and consider their respective obligations on human rights (and) the right to health”.

As the WMA states in its Delhi Declaration on Health and Climate Change, “Although governments and international organizations have the main responsibility for creating regulations and legislation to mitigate the effects of climate change and to help their populations adapt to it, the World Medical Association, on behalf of (…) its physician members, feels an obligation to highlight the health consequences of climate change and to suggest solutions. (…) The WMA and NMAs should develop concrete actionable plans/practical steps” to both mitigate and adapt to climate change (WMA 2009).

RECOMMENDATIONS

The WMA recommends that its national medical associations and all health organizations:

Continue to educate health scientists, businesses, civil society, and governments concerning the benefits to health of reducing greenhouse gas emissions and advocate for the incorporation of health impact assessments into economic policy.
Encourage governments to adopt strategies that emphasize strict environmental regulations and standards that encourage energy companies to move toward renewable fuel sources.
Begin a process of transferring their investments, when feasible without damage, from energy companies whose primary business relies upon extraction of, or energy generation from, fossil fuels to those generating energy from renewable energy sources.
Strive to invest in companies upholding the environmental principles consistent with the United Nations Global Compact (www.unglobalcompact.org), and refrain from investing in companies that do not adhere to applicable legislation and conventions regarding environmental responsibility.

Adopted by the 65^th World Medical Assembly, Durban, South Africa, October 2014
and rescinded and archived by the 75th WMA General Assembly, Helsinki, Finland, October 2024

Preamble

There are a number of ways in which the volume of harmful emissions can be reduced. These include encouraging fewer road traffic journeys, active transport for individuals undertaking relatively short journeys, the use of mass public transit in preference to individual vehicles, and alternative energy sources for vehicles, including electric and hybrid technologies. Where vehicle use is essential, means of reducing harmful emissions should be used.

Physicians around the world are aware of air pollution. It impacts the quality of life for hundreds of millions of people worldwide, causing both, a large burden of disease as well as economic losses and increased health care costs. According to WHO estimates, in 2012, urban outdoor air pollution was responsible for 3.7 million annual deaths, representing 6.7% of the total deaths (WHO, 2014).

Especially, diesel soot is acknowledged as a proven carcinogen (IARC, 07/2012). Furthermore, it has many other toxic effects, most prominently in the cardiovascular (Brook et al., 2010) and respiratory systems (ERS, 2010). Moreover, in the context of global warming, soot, along with methane, is identified as the second most important greenhouse driving force substance after CO2 (Kerr, 2013).

Despite the fact that new vehicles will have to comply with stricter emission standards which take into account most harmful ultra fine particles too, a high-polluting in-use fleet, including off-road vehicles such as construction engines and ships, will continue polluting for many more years.

Background

In many densely populated cities around the world, fine dust concentrations measurable as aerosols exceed up to 50 times the maximum WHO recommendation. High volumes of transport, power generated from coal, and pollution caused by construction machinery are among the contributing factors. People living and working near major (high density volume traffic) streets are most affected by pollutants.
For fighting the health risks mentioned above, there exist a variety of highly efficient and reliable filter systems on the market (Best Available Technology (BAT) filters[1]). They are applicable to all internal combustion engines and they reduce even most harmful ultra-fine particles by a factor of over one hundred.
As soon as 90% of heavy duty vehicles, both, new and upgraded ones, satisfy this standard, health problems attributable to emissions of heavy duty traffic will be greatly reduced, and no further tightening of emission standards will be possible or even needed at all because of an almost total elimination of the pollutant as such.

In a variety of countries on different continents and under varying conditions retrofit or upgrading programs have been successfully performed. The UN’s Working Party on Pollution Prevention and Energy in Geneva has just proposed a technical standard for regulation in their member states, which will be applicable worldwide.

The WMA supports these efforts and calls on policy makers in all countries, especially in urban regions, to introduce regulatory restrictions of access for vehicles without filter, and/or to provide financial assistance to support the retrofitting of in-use vehicles.

Recommendations

The WMA therefore recommends that all NMAs should encourage their respective governments to:

Introduce BAT standards for all new diesel vehicles (on road and off-road)
Incentivise retrofitting with BAT filters for all in-use engines
Monitor and limit the concentration of nanosize soot particles in the urban breathing air
Conduct epidemiological studies detecting and differentiating the health effects of ultrafine particles
Build professional and public awareness of the importance of diesel soot and the existing methods of eliminating the particles
Contribute to developing strategies to protect people from soot particles in aircraft passenger cabins, trains, homes and in the general environment. These strategies should include plans to develop and increase use of public transportation systems.

Abbreviations:

EPA: Environmental Protection Agency (US)

ERS: European Respiratory Society

IARC: International Agency for Research of Cancer

BAT Standards: Emission standards for passenger cars, heavy-duty vehicles and off-road machinery, based on count of ultrafine particles rather than mass and aimed at the protection of human health from the most hazardous soot particles, the lung and even cell membrane penetrating ultra-fines.

References:

Brook, Robert D. et al. (2010): AHA Scientific Statement: Particulate Matter Air Pollution and Cardiovascular Disease. An Update to the Scientific Statement from the American Heart Association. Circulation 121: 2331-2378.
ERS (2010): The ERS report on air pollution and public health. European Respiratory Society, Lausanne, Switzerland. ISBN: 978-1-84984-008-8
IARC (2012): “IARC: Diesel Engine Exhaust Carcinogenic”. Press Release No. 213. http://www.iarc.fr/en/media-centre/pr/2012/pdfs/pr213_E.pdf .
(access: 14/02/14)
Kerr, Richard R. (2013): “Soot is Warming the World Even More Than Thought”. In: Science 339(6118), p. 382.
WHO (2014): “Burden of disease from Ambient Air Pollution for 2012.” http://www.who.int/phe/health_topics/outdoorair/databases/AAP_BoD_results_March2014.pdf?ua=1 (access: 26/08/14)

[1] Euro 6/VI, US/EPA/CARB, Chinese and equivalent standards.