A mum from Fence ditched her car and walked her son to school after reading shocking statistics about air pollution being one of the biggest killers.
And Kathryn Musso is hoping that others will follow her example, even if it is only for one day.
"Air pollution is one of the biggest killers in this country yet everyone hops into their cars to go everywhere," she said.
"It really hit home to me so I decided to walk to school one day."
Kathryn walked just over a mile from her home in Cuckstool Lane, Fence, with her five-year-old son Peppe, to St Mary's Primary School in Newchurch in Pendle on Monday morning.
She said: "Peppe loved it because it was a lovely day and we noticed so much more than when we are in the car."
According to figures from the World Health Organisation more than nine out of 10 of the world's population lives in places where air pollution exceeds safe limits and it is the fourth largest threat to human health behind high blood pressure, dietary risks and smoking.
The health risks of breathing dirty air include respiratory infections and cardiovascular diseases, stroke, chronic lung disease and lung cancer.
Kathryn, who works for the probation service, says she has met with a positive response after her "walk to school" day.
She added: "I realise that not everyone can walk to school because of work and other commitments. For many reasons it is not practical for a lot of people but I hope it is something that parents may think about doing."