Here is everything you need to know about why air pollution is harmful and how to prevent it

A woman wearing a face mask as protection from pollution. Picture credit: iStock/PA
A woman wearing a face mask as protection from pollution. Picture credit: iStock/PA

From smog hanging over cities to streets filled with car emissions, air pollution is one of the biggest environmental threats to our health, and it comes from lots of different man-made sources.

The World Health Organisation (WHO) estimates that over 70 per cent of UK towns and cities have unsafe levels of air pollution, while around 4.2m premature deaths globally are linked to outdoor air pollution, which is associated with serious health issues like heart disease, stroke and lung cancer.

What exactly is air pollution, and do we really need to worry?

An air pollutant is any substance in the air that could cause harm. Tiny pollutants that are too small for the naked eye to see can evade our body’s defences when we breathe them in, damaging our lungs, heart and brain.

Air pollution can disperse widely, so it’s a myth that you can avoid it in the countryside.

Pollution can come from natural sources such as pollen and soil, but it’s often caused by emissions from vehicles (such as from petrol or diesel engines), dust from the road, construction work or burning fossil fuels.

Not only is air pollution harmful to health, it’s also bad for the environment. It has close links to climate change, as burning fossil fuels such as coal and oil releases a variety of chemicals into the atmosphere, including greenhouse gas carbon dioxide.

Why is it bad for health?

Breathing it in can irritate the eyes, nose and throat, cause shortness of breath, make asthma symptoms worse and possibly affect the heart and cardiovascular system.

Being exposed to polluted air for longer periods can cause more serious health problems too.

Dr Antonio Pena-Fernandez, a senior lecturer in biomedical and medical science at De Montfort University, explains: “Studies have found people that breathe contaminated air can develop different conditions including cardiovascular and respiratory conditions, and enhance the likelihood of developing chronic diseases such as cancer, neurodegenerative diseases or diabetes.

How can you protect your health from air pollution?

Regularly monitor the air pollution level around where you live and work, especially if you have asthma or a circulatory condition.

The Government’s UK-AIR website ( has a daily pollution forecast, which tells you if air pollution levels in your postcode are low, moderate, high or very high. On high pollution days, avoid spending long periods of time outdoors - especially areas such as busy roads with heavy traffic. Keep windows and doors closed, and keep your car windows shut, especially if you’re stuck in traffic. If you have asthma, carry an inhaler at all times and take an antihistamine if pollen levels are high.

Pollution can make you more likely to react to your usual asthma trigger, such as house dust mites and pollen, so it’s wise to invest in special hypoallergenic fabrics around the home, says Pena-Fernandez.

There are measures we can all take to help reduce our own carbon footprint and challenge the air pollution problem at the same time.

Opt for energy-efficient light bulbs, use electricity from environmentally-friendly sources where possible and keep your vehicles properly tuned. Better yet, make use of public transport or try cycling or walking to work.