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LONDON, Oct 6 (Reuters) - London's Heathrow airport couldbuild a third runway without breaking European pollution laws,according to research published before a British governmentdecision on airport expansion, the BBC reported on Thursday.
Europe's busiest airport is battling Gatwick, London'snumber two airport, for government approval to build an extrarunway, with a final decision due in the next few weeks aftermore than two decades of deliberations due to local protestsabout noise and pollution.
Heathrow, Britain's biggest port which handles a third ofthe country's non-EU exports, says it can build more routes withtrading nations but has faced greater scrutiny over itsenvironmental impact. Gatwick says it can build a new runway ata lower cost and with less harm to the environment.
In a potential boost to Heathrow, research from theUniversity of Cambridge showed that any increased levels ofpoisonous nitrogen oxide from a new runway would be offset bylower pollution from traffic nearby as cleaner car models becomemore common, the BBC said.
The research, with no formal links to the airport or thegovernment, used small sensors dotted around the airport to pickup changes in air quality more comprehensively.
"There will be more pollution (from the projected runway atHeathrow) but it will be against a background of reducedpollution from the wider area, and so the general pollutionlevel will drop, we think below the critical level we now havefor health impacts," Professor Rod Jones told the BBC.
However Cait Hewitt, deputy director of Britain's AviationEnvironment Federation, told the BBC that basing a decision onthe assumption car emissions would decline was "irresponsible inthe extreme" because there was no supporting evidence.
Heathrow has said it will comply with an extended ban onnight flights and meet European air quality rules if the projectgets the green light.
It has also said it will meet 11 conditions set out byBritain's Airports Commission, including a requirement on airquality which states that new flights will only be permitted ifair quality does not breach EU limits.
The University of Cambridge said the results of the researchhave not yet been published. (Writing by Elisabeth O'Leary; Editing by Guy Faulconbridge andAdrian Croft)
