Parents are worried about their children’s health in the aftermath of bungled asbestos work at a primary school - despite rigorous health assurances from Havering Council.

It is believed the potentially cancer-causing material had not been fully removed from the roof spaces of three rooms and the school hall at Benhurst Primary School, in Benhurst Avenue, Hornchurch, following work carried out by contractors over the Easter break.

The Health and Safety Executive (HSE) has been informed and there have been air and dust tests carried out to ascertain any health risk, the council said in a letter sent to parents last week.

It confirmed: “We wanted to reassure you that we have found no evidence at all to suggest that any pupils have been exposed to asbestos fibres.”

The HSE is not investigating.

A spokesman for the watchdog added: “HSE was informed by the council of the asbestos removal work at Benhurst Primary. We have received assurances from the authority and the school that sampling has been carried out which shows that schoolchildren, staff and visitors are not at risk.”

Sheets of plastic have been taped to the affected areas before permanent work is undertaken during the summer holidays.

Council officers met parents twice last week but some said the assurances did not go far enough.

“There are a lot of worried parents,” one mum said. “Teachers are worried as well. Some of the plastic sheeting came down in the hall and that area is now cordoned off. It doesn’t sound like the school has been made safe.”

Asbestos, now banned but once widely used to insulate buildings, is only dangerous if broken or damaged.

Cleaners working at the school during the works and clean-up are concerned they may have been exposed to dangerous fibres. But the council said there was “no evidence” that this had happened but it is discussing the situation with them.

A second mother said: “There are a lot of concerned parents in the playground. Some people have written to the MP about it. They won’t remove it all until the summer, I think they should do it sooner rather than later.”

Mary Pattinson, head of Learning and Achievement, said: “We completely understand parents’ concerns about this. But we would like to stress that air and dust samples tested when the work was finished showed that the school buildings were safe for the children to use. Every test since then has shown the same. If we had any doubts about this, we would have closed the buildings at the start of term.

“To reassure parents, we will continue to undertake daily air tests before school starts and make the results available to parents. We will not be able to complete the removal of asbestos from the roof void until the school is closed for the summer. So until then we have taken the additional precaution of sealing the ceilings in the block – so we can assure all parents that the school continues to be safe for pupils to attend.”