Staff at the terminus in the city centre said the odour had been lingering inside the building for at least 10 days.

It wasn’t a horrible odour, but not like something I had smelt before.

It said that noise and odour remained within permitted levels - regulated by the Environment Agency - and any complaints were fully investigated with feedback provided to residents.

They have been described by resident Stan Tobin as doughy - "like someone had tried to bake bread and done a lousy job" - with an odour reminiscent of vegetable oil.

People living near the Aycliffe Quarry landfill site in County Durham said, last week, the odour was "off the charts" and "turned their stomachs".