Nitrogen dioxide emissions have dropped at five Welsh traffic hotspots where 50mph speed limits were introduced.
The speed limits were put in place and average speed cameras installed last year at five heavy traffic locations - including the M4 near Port Talbot and Newport - to help bring nitrogen dioxide levels within legal limits.
An interim report on the first 12 months of the 50mph speed limits being in place has shown a reduction of nitrogen dioxide levels at all five locations.
The Welsh Government wants to reduce pollution levels to comply with EU air quality standards and says further evidence is still needed.
I am encouraged by these findings in the first year of these speed limits, but it is vital we continue to reduce emissions in order to save people from the risk of developing potentially serious health conditions.
The speed limits are in place at the following locations:
A494 at Deeside
A483 near rexham
M4 between J41 and J42, Port Talbot
M4 between J25 and J26, Newport
A470 between Upper Boat and Pontypridd
It is vital urgent reductions in nitrogen dioxide emissions are achieved to meet legislative requirements and to support our ambitions for a healthier and more globally responsible Wales. The actions taken on our road network to support driver compliance are an essential component in ensuring that required emissions reductions are achieved.