On Guy Fawkes Night air pollution soars under the impact of millions of bonfires and fireworks to levels far above new limits to be laid down under an European Union directive.
At a meeting in London two weeks ago Department of the Environment officials succeeded in getting 5 November exempted from the new legislation.
Environment Secretary John Gummer says he has "always hated" Guy Fawkes night. But he has delayed the publication of proposals for clearing Britain's air until after tonight.
A year ago today concentrations of tiny smoke particles, thought to cause 10,000 deaths in Britain every year, soared in cities across the country. They reached 200 micrograms per cubic metre of air - four times the new limit to be proposed this week - in Cardiff, Bristol, Leicester and Liverpool, and 300 micrograms in Leeds and Birmingham. In London it was wet and the rain doused fires and washed pollution from the air.
New research by AEA Technology at Harwell reveals that levels of dioxins, thought to be among the world's most dangerous pollutants, soared fourfold last Guy Fawkes Night.Bonfire smoke contains 350 times as much cancer- causing benzopyrenes as cigarette fumes.
The new European legislation aims reduce such particles, which are less than a tenth of the width of a human hair. Environmentalists have pressed for strict limits to be enforced all year.
But at a meeting in London on 19 and 20 October, officials from all EU countries agreed that a handful of days would be exempted. Higher levels of pollution are to be allowed on Guy Fawkes Night and on similar festivals in other countries.
Spain, and the Scandinavian countries light bonfires on Midsummer's Night. Many countries including the Netherlands and Italy set off fireworks on New Year's Eve. Germany has several such festivals, including Rose Monday shortly before Lent.
On Wednesday Mr Gummer will publish a recommendation from his official air pollution advisers, the Expert Panel on Air Quality Standards, for a limit of 50 micrograms per cubic metre. He wants to accept it, but the Treasury and the Department of Transport are resisting.
Measurements by Friends of the Earth show that the limit was exceeded last year almost everywhere the pollutant was measured. Meeting it would involve cutting down on the use of diesel fuel, which emits 10 times as much pollution as petrol.
The National Society for Clean Air says it would not want to ban Bonfire Night, but urges people to minimise pollution by burning only dry wood and avoiding lighting fires when the air is still and smoke hangs in the air.
nDoctors were fighting to save the sight of a promising young footballer yesterday after a firework exploded in his face. Murray Reid, 14, from Mintlaw, near Aberdeen, has had trials for the Scottish schoolboys' team.