Bid to recruit young pollution posse; A regional "air force" is being recruite d to plot pollution levels. Environment Editor Tony Henderson reports.

Byline: Tony Henderson

FORTY or so years ago, today's handsome honey-coloured buildings in Newcastle's Grainger Town were inky black.

This was the result of air pollution from smokestack industries and the days when most homes had an open coal fire.

Against this backdrop, Newcastle University botanist Dr Oliver Gilbert embarked in the 1960s on a pioneering study of air pollution in the North East, using lichens and mosses as biological indicators.

The lichen plant family is especially sensitive to dirty air. In the 1960s, only one lichen, lecanora, which thrives on sulphur, could be found in Newcastle, and even this could not survive in the most polluted areas.

Times change, and grimmia moss, which Dr Gilbert found only on the outskirts of Morpeth in Northumberland, is now widespread.

Its value as a pollution indicator was shown when Dr Gilbert found that it literally split a street of council homes in Morpeth in two.

The houses with central heating had evidence of the moss but those with coal fires did not.

Now around 2,000 volunteers are being recruited in the North East to once again use lichens in the first major air pollution survey since Dr Gilbert's work enabled a similar exercise by schoolchildren in 1974.

The project is part of the Open Air Laboratories (Opal) programme, which is financed by the Big Lottery Fund and being run in the North East by Newcastle University.

The aim is to involve the public, especially young people, in science and environmental activities and to encourage communities to care for their local environments. Volunteers are being given free lichen guides and workbooks to help them locate and examine plants, and also tar spots on sycamore leaves.

Tar spot is a fungal infection but this is suppressed in polluted areas.

"We are encouraging people to find out more about lichen and how they can help map our local area," said Katy Barnard, Opal's education officer for the North East.

"The more people get involved, the better picture we can form of how pollution levels have changed since Oliver Gilbert carried out his research."

How the air pollution picture has changed is illustrated by a recent World Health Organisation report which states that the safe limit for pollution in the air should be no less than 10 microgrammes per cubic metre.

When Dr Gilbert was carrying out his work, the levels averaged 150 microgrammes.

"It was seriously bad, bronchitis-inducing stuff," said Alan Davison, Emeritus Professor of Environmental Biology at Newcastle, and a former colleague of Dr Gilbert, who died in 2005. For his study, Dr Gilbert worked his way from Northumberland, across Newcastle Town Moor and into the heart of the city. Prof Davison said: "He was a very entertaining and larger-than-life character. He had an infectious quality about him and was extremely passionate about his work.

"Oliver was particularly skilled at getting children involved in science.

"You always had a laugh when Oliver was around.

"On one occasion, he was examining lichen in a churchyard in Byker as the dates on the stones helped him to date the specimens.

"While he was lying on a gravestone and peering at the lichen through his hand lens, the police were called and he had a lot of explaining to do as to what exactly he was doing there."

For details of how to take part in the survey, contact Katy Barnard on [phone] or email [e-mail]

CAPTION(S):

PIONEER Dr Oliver Gilbert, who carried out the 1960s survey. LICHEN IT Dan Gordon of Sunderland Museum with an example from their lichen collections.