Tougher clean air targets needed, experts say
22 January 2014 Last updated at 09:18 GMT
A study confirming a link between atmospheric pollution and heart attack risk strengthens the EU case for tougher clean air targets, according to experts.
Research in the BMJ looking at long-term data for 100,000 people in five European countries found evidence of harm, even at permitted concentrations.
Dominic Hughes reports.