The majority of the world’s population breathes air that is harmful, according to a major new study. The State of Global Air report, released in April 2018 by the Health Effects Institute, estimates that 95% of people around the globe live in areas where concentrations of fine particulate matter, such as dust or soot particles in the air, exceed the World Health Organization’s Air Quality Guideline of 10 micrograms per cubic metre of air (µg/m3).
It also found that a third of the world’s population was exposed to high levels of household air pollution from the use of solid fuels for cooking and heating indoors. For these households, the levels of fine particulate matter levels in the home can exceed the WHO’s air quality guidelines by as much as 20 times.
There is a definite link between poverty and air quality. Developing nations can be particularly prone to unsafe air, but there is no room for complacency in a country like the UK. A 2015 study by researchers at King’s College London found that almost 9,500 people die prematurely every year due to long-term exposure to air pollution in London alone. There are also thousands of hospitalisations due to poor air quality every year.
London isn’t the only UK city to face high levels of pollution. According to a recent report, 44 out of 51 UK cities exceeded the WHO safe air guidelines of 10 µg/m3. Glasgow had concentrations of 16 µg/m3, London and Leeds both had 15, Cardiff and Birmingham 14, and Manchester had 13 micrograms of fine particulate pollution per cubic metre of air. This level of pollution has been linked to heart disease and premature death and could also cause or contribute to other health issues.
May 1st is World Asthma Day and, according to Asthma UK, there are 5.4 million people with the condition in the UK, meaning it affects one in five households. For some, the symptoms can be relatively mild and controllable, but the charity says that "every day the lives of three families are devastated by the death of a loved one to an asthma attack. Tragically two-thirds of these deaths are preventable”.
Asthma UK campaigns for cleaner air and its research has found that two-thirds of people with asthma say poor air quality can trigger attacks and makes their condition worse. High spells of air pollution create peaks in GP visits and emergency hospitalisations. Children and young adults can be more at risk from the effects of pollution because they have faster breathing rates, and their lungs are still developing.
Most studies of air quality have concentrated on outdoor conditions, but the air quality indoors is often worse, and not just in developing countries where the use of solid fuels indoors is more commonplace.
A recent study by the University of Sheffield, published in the Journal of Indoor and Built Environment, found that the air in homes across the UK can have pollutant levels up to three times higher than the outdoor environment, including by busy roads and in city centres.
Study author, Professor Vida Sharifi said, "We spend 90 percent of our time indoors and work hard to make our homes warm, secure and comfortable, but we rarely think about the pollution we might be breathing in. Energy is just one source of indoor pollution, but it is a significant one. And as we make our homes more airtight to reduce heating costs, we are likely to be exposed to higher levels of indoor pollution, with potential impacts on our health."
As well as fine particulate pollution, indoor environments can be prone to build-ups of types of contaminants that do not generally exist in high concentrations outside. Radon gas, for example, is released by the natural breakdown of small amounts of uranium present in rocks and soils. Outside, it usually disperses to negligible levels but can sometimes get trapped in buildings and build up to levels that have been linked to increased risks of developing lung cancer.
One way of reducing air pollution in the home is to install adequate ventilation systems, as this can ensure a constant supply of clean, filtered air.