A UNITED Nations committee is to scrutinise Edinburgh's troubled trams project, after campaigners claimed it has resulted in a large increase in pollution in the city.

A hearing to assess Edinburgh City Council's handling of the scheme will be held in Geneva tomorrow before the organisation's Aarhus Compliance Committee. Although its findings are not mandatory, they are said to be highly influential.

Campaigners claim increased pollution levels and noise associated with the infrastructure project will have an impact on the health of local people, a concern which they said the city council never treated seriously enough during consultation with residents.

The UN's Aarhus Convention was designed to give the public a stronger voice on environmental matters.

Alistair MacIntosh, a local resident and retired engineer who put the case to the UN, said: "Our message will be that we have not been fairly treated, that we have not been given the opportunity to explain our case to an independent third party.

"The council are acting as judge and jury. We have not been given essential environmental information relating to the pollution from the traffic which has been driven through the residential streets and we have not been allowed to really participate in decision making."

A spokesman for Edinburgh City Council said they were confident the consultation had been carried out appropriately. He added: "In response to their specific concerns relating to air quality, the council agreed to establish additional monitoring sites in the area in 2010. The results indicated that levels were within EU target values.

"Monitoring is ongoing and the data for calendar year 2011 will be published in accordance with UK guidelines in the spring."

The hearing will come just days after trams began rolling in the city for the first time in a series of trial runs at the network's Gogar depot.