Watch a report by ITV News Anglia's Meteorologist and Weather Presenter Chris Page
St James school in Colchester lies next to one of the most polluted areas of the town, where air pollution levels exceed those set by EU guidelines.
Yesterday (Thursday) was 'Clean Air Day' and children at the school have been talking about how they can help bring those levels down.
For the past year, the council's been running a campaign to get drivers to turn off their engines when stationary.
A giant inflatable ball is being used to show how children can be trapped inside a bubble of poor quality air when they're in a car with the engine idling.
Alastair Lewis is a professor of atmospheric chemistry at the University of York.
The impact on health is startling - according to Public Health England manmade air pollution is the biggest environmental threat to health in the UK, with between 28,000 and 36,000 deaths a year attributed to long-term exposure.
So what can we do?
There are simple solutions that can have an immediate effect. Walking or cycling instead of driving, moving away from gas boilers and log burners, even eating less meat can impact our air quality.
We can also stay aware - keeping an eye on air pollution warnings so we can make the best choices to keep ourselves healthy