New runway at Gatwick or Heathrow 'could damage health'
Expansion of Heathrow or Gatwick airports could be damaging to health, the Green Party has claimed.
Keith Taylor, the Green MEP for the South East said a new runway could be "bad news for air quality".
Both airports have said they would meet legal limits on air quality.
A consultation by the Airports Commission on the issue ends on Friday with a recommendation to the government on airport expansion due in the next few weeks.
The commission ordered a further air quality assessment after the Supreme Court set a deadline for the government to produce new plans for reducing air pollution levels.
It is due to recommend which of the three short-listed schemes - two at Heathrow and one at Gatwick - should go ahead.
However along with the Green Party, local councils in the Heathrow area and the Gatwick Area Conservation Campaign have said the commission has underestimated the environmental impact airport expansion would have.
Mr Taylor said: "The reality is that building any major new runways would be seriously bad news for air quality, rule out any chance of meeting our climate change targets, and would result in an unprecedented increase in noise levels."
Stewart Wingate, Gatwick's chief executive, agreed air quality was now "even more fundamental" to expansion decisions.
"[But] Heathrow currently breaches legal air quality limits and it defies common sense that a third [Heathrow] runway will solve the problem," he said.
"In contrast, Gatwick has never breached legal air quality limits and its location means it can guarantee that it never will."
Matt Gorman, Heathrow's sustainability and environment director, disagreed with Mr Wingate's assessment.
"The commission's air quality analysis has confirmed an expanded Heathrow will go beyond meeting local air quality limits," he said.