RESIDENTS living on the route of Scotland's most expensive transport project fear building work will disturb highly toxic, cancer-causing chemicals.

A public inquiry into the five-mile, (pounds) 500m M74 northern extension in south-east Glasgow begins on Monday.

The route passes the site of White's chemical factory in Rutherglen, which operated for 150 years before it closed in 1967.

White's used chromium ore in the production of chemicals and dumped waste products across the area at a time when there were no regulations to control disposal of hazardous material.

Dr John Farmer, an environmental chemist at Edinburgh University, investigated the deposits of chromium in the Rutherglen area in a study into contaminated land sites in central Scotland.

He found chromium hexavalent 6, which can cause cancer.

Dr Farmer said that disturbing chromium could be fatal.

''If chromium dust is inhaled it can lead to problems such as lung cancer,'' he said. ''Anything that was going to physically disturb these sites would have the capacity to increase dust in the atmosphere.''

Monty Borthwick, a former worker at White's who still lives in Rutherglen, said colleagues who were exposed to chromium had developed cancers and permanent scars on their skin where they had been burned by the chemical.

An environmental impact report into the new road said the contractor would be given guidelines to manage the polluted land.

Several of the sites along the route are also contaminated with heavy metals, asbestos and other chemical agents.

Tom Martin, who has lived in Rutherglen for 30 years, said: ''I am worried about the controls that will be put on the firm that builds the road.''

Charles Gordon, leader of Glasgow City Council, said building the new road would ensure the land was decontaminated.

He said: ''Without the road, he said, it would be difficult to make an economic case for the clean-up.

A public inquiry was triggered because 40 businesses, including Network Rail, the owner of Britain's railway network, formally objected to being served compulsory purchase orders, which mean their premises will be demolished to make way for the highway.