Around the world, more than eight out of ten people who live in cities breathe in concentrations that exceed WHO air quality guidelines. But it's not just in urban areas that you're at risk. You might think that's the healthier option, but toxins from inorganic fertilisers and ammonia from chicken broiler units are just as likely to exacerbate asthma and other lung diseases.

Hay Festival Sustainability Director Andy Fryers interviewed Tim Smedley about his book Clearing the Air: the beginning and the end of air pollution. As the title suggests, there are solutions as well as alarming statistics. 

"We have the highest number of asthma deaths in Europe. But levels of heart disease are even worse," said the author. "Air pollution is all about exposure to it. If you are a daily jogger in a city, choose a route well away from traffic, in a park if possible." 

The culprit is particulate matter (PM) – hundreds and thousands of tiny particles from a car's exhaust pipe that are absorbed into the bloodstream. When there was a spike in diesel in the UK, the knock-on effect on our health was dramatic, and continues to be. Cutting-edge research has shown that dementia rates have risen as and continue to do so on expose to PM. "The nano particles have a huge impact on health costs, productivity and potential. Breathing in pollutants is reducing what we are capable of."

"One solution is to stop burning stuff – in a domestic context that means logs and coal." A recent focus has been on log burners – to minimise damage, always use dry, well seasoned logs. "Electric buses and improved facilities for walking and cycling would be a huge help," said Smedley.

Picture by Philippa Harris

This talk was part of the sustainability strand, #GreenHay.

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