Better air, better health: why dirty air makes your patients sick

Introduction

Air pollution represents the greatest environmental threat to health and is a leading cause of non-communicable diseases (NCDs), such as heart attacks or stroke (World Health Organization (WHO), 2021). Air pollution represents a public health emergency, causing 36,000 premature deaths in the UK every year (Committee on the Medical Effects of Air Pollutants (COMEAP), 2018). It is associated with a higher risk of hospital admission for cardiovascular and respiratory diseases (Ab Manan et al, 2018) and, thus, affects the workload and cost of health and care systems; this has been estimated to total £157m a year (Public Health England (PHE), 2018a). In addition, there is the associated health impact on people, families and communities.

Clean air is a basic human right (United Nations (UN), 2021). In the UK, while air pollution that exceeds international targets affects all of us, air pollution disproportionately affects the most vulnerable (UN, 2018).

What is air pollution?

Air pollution is defined as “contamination of the indoor or outdoor environment by any chemical, physical or biological agent that modifies the natural characteristics of the atmosphere” (WHO, nda). The term ‘air quality’ describes how polluted the air we breathe is. When air quality is poor, the pollutants in the air may be hazardous to people’s health and wellbeing, particularly for those who have lung or heart conditions (Department for Environment, Food and Rural Affairs (Defra), 2019).

Types of air pollution

Air pollution arises both indoors and outdoors. Pollution indoors mainly arises from fuel burning and from chemicals that are used in the home; outdoors, it arises from many sources, including traffic and industry. The main pollutants of public concern include particulate matter (PM), nitrogen oxides and sulphur dioxide (Fig 1 and Box 1).

Data shows that, although the media often focus on transport, farming and heavy industry, significant air pollution comes from the domestic combustion of fuels. As an example, the increased popularity of wood-burning stoves, in particular, has led to a stalling of reductions in PM nationally (Defra, 2019). Fewer vehicles and a switch to electric vehicles may reduce exhaust emissions, but will not stop particulate emissions every time the brake is applied when driving or from the wear of car tyres. A reduction in air pollution, therefore, isn’t just an issue for local and national governments to address – it is one for us all to address.

What does ‘net zero’ mean?

Reaching net zero emissions means removing an equal amount of carbon dioxide (CO2) from the atmosphere as we release into it. Greenhouse gases include CO2 and methane. Methane is produced through farming and landfill. CO2 is released when oil, gas and coal are burned in homes, factories and to power transport. These gases cause global warming by trapping the sun’s energy. A warmer planet means nurses will have to deal with issues like heat stroke, disrupted food supplies and rising energy costs (Morris, 2023).

Morbidity and mortality

It is estimated that long-term exposure to air pollution in the UK has an annual effect that is equivalent to 28,000 to 36,000 deaths (COMEAP, 2018). PM that is >10 microns (µm) mainly settles in the nose or throat. Anything measuring <10µg (smaller than a strand of hair (Fig 2)) is considered to pose the biggest risk to health, with the greatest evidence for adverse health effects associated with fine particles (<PM2.5) (PHE, 2018b).

PHE (2018b) modelled what would happen if there was a 1µg/m3 reduction in PM2.5 in England in a single year over the next two decades; it estimated that, over the next 18 years, the following could be prevented:

• ~50,000 cases of coronary heart disease;
• ~16,500 strokes;
• ~9,000 cases of asthma;
• ~4,000 lung cancers.

Impact on the major systems of the body

Air pollution can have a significant impact on human health and wellbeing, both in the short term and the long term. It affects various systems of the body in different ways, depending on the type of pollutant, the level and duration of exposure, and the individual’s health status (PHE, 2018b). Because of air pollution’s widespread effects, most (if not all) nurses will be dealing with its effects on:

• Respiratory system – air pollution can irritate the airways and cause inflammation, resulting in respiratory problems such as coughing, wheezing and shortness of breath. Exposure to air pollution has been linked to the development and exacerbation of respiratory conditions such as asthma, chronic obstructive pulmonary disease and bronchitis (WHO, ndb);
• Cardiovascular health – air pollution can increase the risk of heart disease and stroke. Air pollutants can cause inflammation, oxidative stress and damage to blood vessels, which can lead to atherosclerosis and other cardiovascular problems (WHO, ndb; WHO, 2022a);
• Lung cancer – long-term exposure to air pollution has been linked to an increased risk of lung cancer (WHO, ndb; WHO, 2022a; International Agency for Research on Cancer, 2015);
• Immune system – air pollution can affect the immune system by causing inflammation and oxidative stress, which can weaken the body’s defences against infections and other diseases (WHO, ndb);
• Mental health – air pollution has been linked to a range of mental health problems, including anxiety and depression (Newbury et al, 2021);
• Nervous system – some air pollutants, such as lead and mercury, can cause developmental neurotoxicity, and may contribute to the aetiology of neurodevelopmental disorders and neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease and autism spectrum disorder (Asthma UK and British Lung Foundation, 2021; Costa et al, 2020);
• Reproductive system – exposure to air pollution has been linked to pre-term birth, foetal growth restriction, increased uterine vascular resistance, impaired placental vascularisation, increased gestational diabetes and reduced telomere (a compound structure at the end of a chromosome) length, affecting fertility (WHO, ndb; Gómez-Roig et al, 2021);
• Premature deaths – air pollution is a major contributor to premature deaths worldwide. Outdoor air pollution is responsible for an estimated 4.2 million premature deaths globally each year. Indoor air pollution, from actions, can cause an additional 3.8 million premature deaths annually (WHO, 2022b; PHE, 2018c).
• Impact on wellbeing – poor air quality can reduce visibility and create an unpleasant smell, making it difficult to enjoy outdoor activities. It can also contribute to a sense of unease and anxiety about the impact of pollution on the environment and future generations (Asthma UK and British Lung Foundation, 2021).

Environmental injustice

Nurses should care about air pollution because it impacts the most vulnerable people. A post-Covid-19 pandemic report by MPs on the Environment, Food and Rural Affairs Committee (2021) quoted Sir Michael Marmot’s epidemiological association between poverty, poor air quality and higher Covid-19 infection rates. Action on health inequalities, the report concluded, must, therefore, include action on air quality.

In terms of regional statistics, the WHO (2022b) reported that the greatest burden of air pollution-related deaths was borne by low- and middle-income countries in Asia and Africa. However, air pollution is a global problem and even high-income countries with low levels of pollution still experience significant health impacts (PHE, 2018b).

The Invisible Threat, a (2021) report by Asthma UK and the British Lung Foundation (now known as Asthma and Lung UK), highlighted that:

• Vulnerable people become prisoners of air pollution, feeling unable – perhaps due to chronic breathing problems – to leave their own homes, which has a knock-on effect on their mental health;
• 85% of people living in areas with illegal levels of NO2 (usually close to busy roads) are also in the poorest 20% of the population. The poorest communities often cannot afford a car and yet their health is damaged by the pollution created by more-affluent people driving past their homes;
• Health and care staff, and the people they support, are unequally affected by unsafe levels of pollution because healthcare buildings are close to busy roads. Toxic air affects >2,600 GP practices and 300 hospitals.

Air pollution affects children more than adults, causing prematurity, low birth weight and smaller lung growth (UN, 2018), something that will affect lung health throughout life. A third of children in the UK are breathing unsafe levels of air pollution (Edwards and Wellesley, 2019). Children are at more risk because they walk the streets at vehicle exhaust height, breathe faster and do so more often through their mouths, so the air is not filtered by their noses. They also have immature immune systems so, compared with adults, white blood cells or macrophages are less able to deal with particulates (Edwards and Wellesley, 2019).

Early labour may be triggered by pollutants from the mother’s blood, which also affect the normal development of the foetus. Research by Liu et al (2018) suggested that the unborn child will be affected because of particulates in the placenta, and it may also be possible for carbon particles to move from the mother’s lungs into the foetus. This research also suggested an 18% increased likelihood of babies being underweight at birth, posing an increased risk of developing pneumonia or even infant death in early life.

A political issue

Air quality is highly political and, as it affects health and care, is something that nurses everywhere need to understand. Different organisations have responsibilities, and funding to achieve changes can be lacking (Harvey and Horton, 2023). Changes to family, industry and business working practices – examples of which include purchasing less-polluting vehicles, changes to farming practices and reducing emissions from factories – are costly and often resisted.

The responsibility for the development of strategies and targets in relation to air pollution is devolved to the four national governments of the UK, making an overall UK plan difficult and agreement occasionally contentious. Added to this, local authorities are responsible for reviewing and assessing air quality, to check that they meet national air-quality objectives. If they are falling short, they must declare the area to be an Air Quality Management Area and produce an action plan showing what they will do to meet standards.

After the UK left the EU, the Environment Act 2021 was passed into law. The act introduced new legally binding environmental targets to be enforced by a new, independent Office for Environmental Protection that would hold government and public bodies to account on their environmental obligations.

Defra’s (2022) environmental targets were announced as part of the act. These were much criticised by environmental campaigners because the government proposed air-quality limits that would allow twice as much small-particle pollution in England as the upper limits recommended by the WHO, and that would not be met for almost 20 years (Harvey, 2022). This led campaigners to conclude that the UK government would continue to leave millions of people exposed to dangerously dirty air.

Defra’s (2023) environment plan followed, with the environment minister admitting that, as the government cannot achieve the air-quality improvements were advised by medical experts, it has set lower targets for the next 10 years (Harvey and Horton, 2023).

“85% of people living in areas with illegal levels of nitrogen dioxide (usually close to busy roads) are also in the poorest 20% of the population”

Clean air zones

One particularly contentious area that is of relevance to nursing, especially those organisations supporting local authorities or managing vehicle fleets, is the creation of clean air zones (CAZs) or ultra-low emission zones (ULEZs) as part of local authorities’ air-quality action plans. Staff and patient travel, as well as the transportation of supplies and waste, for example, can result in significant emissions from cars, lorries and vans.

While some conurbations have successfully introduced CAZs and ULEZs, other plans have remained highly contentious, and progress has stalled. In Greater Manchester, for example, the focus has been on enabling local businesses and public transport providers to swap to lower-emission vehicles, but affordability has been a key factor (BBC, 2022), with some threatening that their businesses would close. Mayor Andy Burnham asked the government to delay phase two of Greater Manchester’s CAZ until plans could be fully funded. Essentially, this means that the economic needs of businesses win out over health – a fact that all nurses need to recognise and consider in terms of their votes and campaigning.

The role of nurses in reducing air pollution

Nurses can play an important role in reducing air pollution and promoting environmental health through:

• Patient education – nurses can educate patients about the health risks associated with air pollution and how to reduce exposure. This can include information on avoiding outdoor exercise during high pollution days, how to use air filters and purifiers at home, how to reduce indoor pollution sources such as tobacco smoke and by avoiding the installation of wood burners. Nurses should act as role models, for example, by using public transport where possible;
• Advocacy – nurses can advocate for policies and programmes that promote clean air, such as supporting the development and use of sustainable public transport, promoting renewable energy and encouraging the use of energy-efficient technologies;
• Workplace practices – nurses can adopt environmentally sustainable practices in their workplaces, such as reducing waste, switching to remote working and consultations, using energy-efficient equipment and promoting green products;
• Research – nurses can conduct research on the health effects of air pollution, and contribute to the development of evidence-based strategies to reduce exposure and improve health outcomes;
• Community outreach – nurses can work with community organisations and public health agencies to promote awareness of air pollution, and encourage community-based initiatives to reduce emissions and improve air quality;
• Nurse education – educators can include sufficient content in pre- and post-registration education on environmental health, including the impact of environmental factors such as air pollution, climate change and toxic exposures on human health. They can promote sustainability principles, such as reducing waste, conserving resources and promoting environmental stewardship. They can also prepare nurses to address the health impacts of climate change, develop adaptation plans and facilitate disaster preparedness;
• Strategic planning – at board level, nurses will be working to achieve the targets set out in chapter 2 of The NHS Long Term Plan, namely that “the NHS will work to reduce air pollution from all sources. Specifically, we will cut business mileages and fleet air pollutant emissions by 20% by 2023/24” (NHS, 2019).

Conclusion

Illegal levels of air pollution are all around us and making us sick, and research is uncovering more pollution-related illnesses than ever. The NHS contributes to this pollution and its organisations are taking action to reduce levels of toxic air. All nurses need to be aware that human rights are being eroded and that there is significant environmental injustice.

Action to improve air quality is costly and difficult and, therefore, contentious. Politicians and governments have been criticised for setting air-quality targets that clinical leaders advise are unsafe. Nurses have a responsibility to understand the issues, provide accurate clinical advice, change their practice, where possible, to reduce the negative impact on the environment, and to act as role models.