Melanie Simmonds, head of Save the Children Wales, said: “In Wales and across the world, children are breathing in smoke from wildfires, coping with extreme heat and losing the freedom to play outdoors because the air is no longer safe.

“These conditions are not only frightening – they carry serious health consequences for children whose bodies and lungs are still developing.”

Torfaen council said it was not aware of the research and “it is not clear what data or evidence was used in the assessment to arrive at the reported conclusion”.

It said it “recognises that prolonged wildfire incidents have the potential to adversely affect local air quality, particularly through increased levels of smoke and particulate matter”.

It added it “continuously monitors” air quality through a monitoring station in Croesyceiliog Cwmbran.

“While elevated particulate concentrations have been observed during the wildfire period, the council’s monitoring station is intended to provide information on general background air quality rather than conditions at specific locations immediately adjacent to the fires,” it said.

The Copernicus Atmosphere Monitoring Service (CAMS) website, external said it was part of European Union’s Space programme, and provided global information related to air pollution and health.

Its data said emissions in Torfaen had been “extremely unusual”.