suggest to others they do a few times a day to catch our breath after some exercise or to just take a break after some particularly stressful or hard activity. But what happens when the air that we inhale to relax or bring our body back into balance contains a lot more than oxygen?
Unfortunately, most of the air we breathe is polluted. The horror stories about China’s pervasive air pollution which costs the life of more than one million people every year are shocking and show no signs of improvement. For weeks during early 2017, northern China has been covered in a thick toxic smog, considered as one of the worst episodes of air pollution the country has seen, affecting 460 million people1. But we should be under no illusions: air pollution is not just an issue for countries with a large industrial base fuelled with coal, such as China, or developing nations which don’t have the technology or know-how. It is a reality across the globe, including in Europe and North America.
About 9,000 people die prematurely because of air pollution in London alone 2.
A World Health Organisation (WHO) report issued in September 2016 revealed that 92% of the world’s population lives in places where air quality levels exceed WHO safe limits for pollutants contained in air3. The report, issued with the support of the University of Bath in the UK, provides an overview of the cost of air pollution to our society and environment: in 2012, an estimated 6.5 million deaths (11.6% of all global deaths) were associated with indoor and outdoor air pollution together 3. Sources of outdoor air pollution tend to be the combustion of fuels for transport, power generation or other human activities while indoor air pollution can be cause by a range of activities such as smoking cigarettes (tobacco smoke), cooking or heating with biomass fuels or coal.
These are some staggering findings which we cannot afford to leave unaddressed. Indeed, in 2015, leaders from across the globe set a target within the Sustainable Development Goals to reduce the number of deaths and illnesses from air pollution by 2030. Associated with this commitment, in 2016 the WHO adopted a plan for accelerated action on air pollution and its causes.
What are some of the diseases caused by air pollution?
Sadly, a 2013 assessment by WHO’s International Agency for Research on Cancer (IARC) concluded that outdoor air pollution is carcinogenic. The particulate matter component of air pollution was found to be closely associated with increased cancer incidence, especially cancer of the lung as well as – to a lesser extent – with an increase in cancer of the urinary tract/bladder4.
Particulate matter, or PM, is a complex mixture that may contain soot, smoke, metals, nitrates, sulphates, dust, water and tire rubber. Sources of particulate matter can be either direct emitters such as smoke from a fire, or it can be formed in the atmosphere from the reactions of gases such as nitrogen oxides5. The size of the particles is what determines what kind of health problems they may cause. Small particles (known as PM 2.5 or fine particulate matter) pose the greatest problems as they can penetrate deep into your lungs and some may even get into your bloodstream.
Particulate matter has not only been linked to lung cancer, it has also been associated with cardiovascular diseases. The small particles of air pollution can begin to irritate the lungs and blood vessels around the heart which over time aggravates or increases the process of disease in the arteries6. According to the American Health Association, while many factors contribute to heart disease such as genes and physical health, long term exposure to polluted air increases the risk of death as air pollution facilitates atherosclerosis – this is the build-up of fatty material inside arteries – development and progression6.
What is more, even short term exposure to air pollution can increase the risk of a heart attack, a stroke, arrhythmias or heart failure in susceptible people, such as the elderly or those with pre-existing medical conditions. According to the WHO, 94% of premature deaths associated with air pollution are due to noncommunicable diseases such as the ones described above3.
But data suggests that air pollution is also responsible for chronic obstructive pulmonary disease and increases the risks for acute respiratory infections. Chronic obstructive pulmonary disease (COPD) is mostly linked to exposure to tobacco smoke, however, in lower income countries the disease is attributed mainly to the use of biomass and coal for cooking, heating and other household needs. With 3 billion people worldwide following such practices, this is an important consideration7.
Particularly vulnerable to the effects of air pollution are also children whose respiratory system is still developing. Over 20 million people in the U.S., including six million children, suffer from asthma. This high prevalence of this disease, with global trends indicating that it is on the rise, can also be at least partly explained by increased air pollution8.
One of the most commonly detected air pollutants, ozone, is formed when volatile organic compounds react with nitrogen oxides in the presence of sunlight. Ozone irritates the lungs at concentrations which are common in urban settings, particularly during the summer months. In other words, increases in ozone levels are linked to asthma and other lung diseases9.
What makes children particularly vulnerable is the fact that they tend to breathe through their mouth, bypassing the filtering effects of the nasal passages; they also have a large lung surface area relative to their weight and inhale relatively more air, compared to adults.
It is clear that air pollution can really damage our health. But decisive action to eliminate air pollution can yield results quickly and substantially improve our quality of life. For example, WHO guidelines indicate that reducing annual average particulate matter concentrations to the WHO guideline levels could already reduce air pollution-related deaths by around 15%4.
We also need our governments to adhere to commonly agreed standards, such as the EU’s National Emissions Ceiling Directive which sets maximum limits for air pollutants, as well as to take stringent action when industries, such as the automobile industry misinform consumers about emissions as was the case with Dieselgate and the 2015 Volkswagen emissions scandal.
A lot of environmental charities and NGOs, such as Friends of the Earth or Client Earth, are working hard to improve air quality around the world. Help support their activities – it will be a breath of fresh air!