By Russell Findlay

Education secretary John Swinney has ordered independent experts to investigate a school campus built on a toxic landfill site over growing concerns about pupil and teacher safety.

The Scottish Government's intervention follows calls from former health secretary Alex Neil MSP to vacate St Ambrose High and Buchanan High in Coatbridge, Lanarkshire.

It comes as a public health expert and teaching union leader join a growing chorus of concerns which has seen some teachers voting to strike and pupils being kept at home by worried parents.

Mr Swinney, Deputy First Minister, said there have been "a number of significant concerns raised by families, teachers and elected representatives".

He added: "I recognise that North Lanarkshire Council and NHS Lanarkshire have undertaken extensive work in an effort to address the concerns expressed by the local community.

"However in light of continuing concerns being raised, ministers have agreed with North Lanarkshire Council and NHS Lanarkshire to immediately commission an impartial, independent review."

It will be lead by the Scottish Government's chief planning reporter Paul Cackett and Dr Margaret Hannah, a former director of public health.

Professor Andrew Watterson of Stirling University's faculty of health science believes that parents and teachers have 'genuine concerns' over the safety of attending St Ambrose High and Buchanan High in Coatbridge.

Four teachers were been diagnosed with rare bladder cancer, one pupil has gone blind while others have reported ill health - but North Lanarkshire Council and the NHS say the illnesses were not caused by the site which they say is safe.

Initial concerns were raised about 'blue water', caused by copper pipes, but parents say of greater concern is what lies beneath the campus which was built on a former landfill site containing household and metal industry waste.

Professor Watterson was one of around 300 at a public meeting at the campus last week - and like many parents he was unconvinced. He says a council website intended to alleviate concerns does not adequately show how conclusions were reached.

He told STV News: "It doesn't contain all of the information that allows you to asses exactly what problems there may be, whether they've been problems in the past and how they have been resolved.

"I think there are genuine concerns there. If things had been transparent, if there had been a high level of trust and if there had been good communication, I don't necessarily think we would be in the position we are in.

"Because those things haven't happened, I think the concerns of the staff and parents are valid. There are issues about how information has been disclosed and where it is and how people can find it - all of those things are real concerns about the process as well as what the risks are and how they have been assessed."

St Ambrose has around 1200 pupils and shares the site with Buchanan which serves around 100 children with additional support needs. The campus opened in 2012.

STV News asked the council how many pupils were absent from both schools on Friday (the day after the public meeting) and Monday. The council responded by providing figures for St Ambrose on Monday when there were 262 absences of which 147 were 'unauthorised'.

Pauline McMullan has kept her S2 son Aidan off school since Friday and is considering paying £500 for private blood tests for lead, arsenic, zinc and cadmium.

She said: "I can't believe I've had to take Aidan out of school. Our education for our children is extremely important. We want them educated in a safe environment."

Asked what the council should do, she said: "Talk to us, be more transparent. Give us dates, gives us times. Explain to us why you feel our children are safe because just giving us the opinion that they're safe, that's not reassuring me to send Aidan back to school."

More than 13,000 people have signed an online petition calling for an independent investigation and testing of pupils and teachers for levels of dangerous substances in their system.

One of the four teachers with bladder cancer told the Sunday Post newspaper: "I decided to speak out because I was so angry after attending the public meeting on Thursday which was supposed to allay fears and reassure staff and parents. In fact, all it did was make everyone very angry because nobody feels we are being told the full truth."

Around a dozen members of the NASUWT union will strike later this month but the larger EIS union says its members have not called for similar action and it accepts the site is safe.

However, the EIS is "actively pursuing legal remedy" on behalf of two members diagnosed with bladder cancer.

Director general Larry Flanagan cited 'significant and legitimate health and safety concerns', adding: "Unfortunately, in this instance, North Lanarkshire Council's response has been poor - in fact the EIS would go as far as saying that it has done far too little, far too late; for example the EIS had to resort to making Freedom of Information requests to gain access to health and safety information and reports which should have been readily provided. This only served to generate suspicion and mistrust.

"We are very clear that North Lanarkshire Council remains liable for ensuring the safety, health and wellbeing of both pupils and staff in their buildings and for taking whatever steps are necessary to provide reassurance such as access to health monitoring."

A council spokesman added: "Specialist doctors from the public health department of NHS Lanarkshire have confirmed that no incidence of cancer is linked to the schools. They have also confirmed that no other serious illness is connected to the schools or the site on which they are built.

"The council will continue to liaise directly with trade unions on matters of concern to staff. All the facts demonstrate that the schools and the site on which they are built is safe."