Staff at a hospital where two children’s deaths were linked to problems with the building’s environment “played down” concerns about water safety, an inquiry has heard.

The inquiry is investigating the construction of the Queen Elizabeth University Hospital (QEUH) campus in Glasgow and the Royal Hospital for Children and Young People and Department of Clinical Neurosciences in Edinburgh.

It is hearing evidence into problems at the two flagship Scottish hospitals that contributed to the deaths of two children.

Colette Gough’s 10-year-old son was diagnosed with cancer after he became unwell in July 2018, aged seven, and was found to have a kidney tumour.

The following month he was being treated in Schiehallion unit, the children’s cancer unit in the children’s hospital on the QEUH campus.

Alastair Duncan, counsel to the inquiry, asked Mrs Gough: “Was there an indication over this period that there might be some concern about the safety of the water that was being used in the Schiehallion unit?”

She replied: “Not from any member of staff. There were signs on the sink saying not drinking water, and don’t pour anything down the drain.

“When we were first admitted there were no water filters on any of the taps but by our second or our third admission, at some point in that first month the tap filters appeared, and I questioned, ‘Oh, what are they?’

“When we asked we were told ‘Oh, there has been an issue with the water, it’s just to keep everybody safe’. The caveat for everything was it’s just in case.”

She said when they later asked about this, staff played down concerns.

Reading from the statement she submitted to the inquiry, she said: “We were told by the staff that there had been issues with the water at the start of the summer.”

The statement continued: “It was very much played down by the staff when you asked about it. They said to use bottled water, the filters are on the taps and not to touch them or interfere with them and that was it.”

The inquiry was ordered after patients at the Glasgow hospital died from infections linked to pigeon droppings and the water supply, and the opening of the Edinburgh site was delayed due to concerns over the ventilation system. It began hearing evidence on Monday.

Earlier this year, an independent review found the deaths of two children at the QEUH campus were at least in part the result of infections linked to the hospital environment.

The review investigated 118 episodes of serious bacterial infection in 84 children and young people who received treatment for blood disease, cancer or related conditions at the Royal Hospital for Children at the campus.

It found a third of these infections were “most likely” to have been linked to the hospital environment.

Two of 22 deaths were “at least in part” the result of their infection, it said.

The inquiry in Edinburgh, chaired by Lord Brodie, continues.