It is a source of relief that Chris Smith, the new head of the Environment Agency, has come out against expansion at Heathrow on health grounds.

In the current mood the Government may be reluctant to give up a lucrative source of income such as the airport, but there comes a time when the powers that be cross a line and I think they've done that with this proposal.

It's vital that Britain and the West show the world that this is not the way to build a sustainable future.

It would be hard for developing countries to stomach not getting the chance to live the luxurious lifestyle that Europe and America have been enjoying for decades, and the temptation in the West is to then compete for business rather than stand back and say they're not going to take part in air travel expansion plans and lose out on income and market share. That may be a pill too bitter for many.

But it shouldn't just be about Britain halting expansion plans, particularly at Heathrow, although it is an important first step in protecting the environment. Having access to six runways and 24-hour flights and all its incumbent supporting services should not be a citizen's right or a country's main economic aspiration. There has to be a sea change in the way we live and the frequency with which we fly.

But for those who disagree, remember the extreme examples of pollution in recent decades such as Chernobyl. Although increasing pollution, even beyond EU guidelines, is not going to kill us within a few months, or deform our unborn children in the same way as nuclear fallout, it will just as surely make us suffer ill health in the medium to long term.

It will probably increase incidences of cancers and other serious lung and heart diseases. It may increase west London's prosperity for a time, but then all who have embraced that, or had that forced upon them, will be needing more medical support than ever before.

Some may be too ill to work and be a burden on the benefits system. And it won't just affect west London. Planes fly over the whole of London to get to Heathrow.

I was in the Globe theatre a couple of weeks ago. It is authentically Shakespearean in every detail, except one - the frequent noise of planes passing overhead as they start to approach Heathrow. They weren't much quieter there than they are here, and I live about three miles from the end of the southern runway.

ANGELA SHARP Church Stretton Road, Hounslow.