AN INVESTIGATION has been launched at a building site in Bournemouth town centre after three quarry workers who ‘inhaled an unknown substance’ were hospitalised.

Bosses at MB Wilkes, a quarry in Corfe Mullen, have written to all of their staff informing them of a ‘serious incident’, which occurred last Thursday, when sand was delivered from contractors working at the West Central construction site in Exeter Road, previously an NCP car park and before that a bus station.

The letter from directors Paul and David Wilkes said the affected employees, who the Echo understands had suspected kidney problems, have undergone blood tests.

The letter said: “The substances are unknown at this point but could potentially have serious health risk implications.

“At this time we believe that the effects are limited to these three members of staff.”

The letter, dated May 16, said the blood test results will take ‘another seven days’.

A Public Health England spokesperson said the symptoms were ‘short-lived’, but that the cause is still unknown and tests are being carried out on the materials.

She added: "At the current time there is no ongoing risk to public health as the material has been contained and left untouched.

“Once test results are known, PHE's Centre for Radiation, Chemical and Environmental Hazards can advise the local authority regulators, Bournemouth Borough Council and the Environment Agency, which regulates waste disposal sites, on any potential effects on health.”

An Environment Agency spokesperson confirmed that the matter was being investigated, adding: “We have told MB Wilkes to quarantine this small amount of waste until tests have been carried out on it.

“We are investigating the site where the waste material came from and taking action to ensure no more of that waste is excavated until tests are completed – and don’t want any more disturbance there.”

The Health and Safety Executive said it too was aware of the incident and has been making 'preliminary enquiries'.

The 120,000 sq ft site is being developed by Licet in a £50million cinema and restaurant scheme, with Vinci Construction winning the contract to undertake the work.

Licet director Chris Dymond said: “All issues of safety in connection with this development are a top priority and taken extremely seriously by ourselves and our building contractor.

“A thorough assessment is underway, additional precautionary procedures have been actioned and test results are awaited. All concerned with the project will continue to work with the relevant authorities to investigate matters fully.”

Mike Holmes, Bournemouth council’s service director for planning, said the authority is ‘certain’ there is no risk to the public.

He added: “Excavation work on the site has ceased and will not recommence until all the issues are resolved.”

The Daily Echo contacted MB Wilkes and Vinci Construction for comment, but neither responded.