More schools in Scotland have been confirmed to contain a collapse-risk concrete, Scotland’s First Minister said as he pledged to review refurbishment applications “through a Raac lens”.

Speaking at First Minister’s Questions on Thursday, Humza Yousaf said reinforced autoclaved aerated concrete (Raac) has now been identified in 40 schools, with further investigations under way.

Ministers were informed of the substance “years” ago, he said, after it was linked to the collapse of a school roof south of the border, where more than 100 schools are set to close as a result of remedial works.

In Scotland, urgent work is under way following the discovery of the concrete at St Kentigern’s Academy in Blackburn, West Lothian, with part of the estate including the kitchen and dining area closed, while Preston Lodge High School in East Lothian has closed impacted classrooms.

In response to a question from Scottish Labour leader Anas Sarwar, the First Minister said: “I can confirm that, given we have further information back from local authorities, 40 schools have been identified that have Raac in them, and of course the appropriate mitigations have been put in place.

Mr Sarwar urged the First Minister to “urgently” prioritise schools which have applied to the Scottish Government’s Learning Estate Investment Programme (LEIP) which will see refurbishments carried out, or new schools built.

Local authorities applied for the scheme, which contributes to urgent infrastructure priorities, and were due to hear back by the end of 2022.

It is understood five schools which are confirmed to have Raac had applied to the scheme.

Mr Sarwar said: “The Government has delayed the next phase of their school rebuilding programme. Local authorities submitted bids a year ago, they were meant to get an answer by the end of 2022 and we know that at least five of the schools on that list contain Raac, although I suspect that number will be far higher.

“Those schools are still waiting so this must be dealt with urgently.”

In response, the First Minister said: “In terms of the school estate, we will be making decisions on LEIP imminently, but we are also now looking at that programme through a Raac lens, I think it’s important to do so.

“This Government does have a good record when it comes to building schools, or indeed substantial refurbishments of schools.

“Since 2007/8 we’ve had 1,098 school buildings or indeed substantial refurbishment projects that have taken place.”

Mr Yousaf also said 254 NHS buildings are believed to have Raac, after a desktop review found two or more characteristics in each.

Following more extensive surveys, nine of 40 medical buildings surveyed so far have Raac, he said.