Headteachers have to pick up discarded needles and condoms from school grounds as janitors refuse to do it on health and safety grounds, a government report has claimed.

A poll of 1,137 headteachers across Scotland reveals mounting concern over the number of hazardous duties they are required to perform because ancillary staff are unwilling or unable to carry them out.

Headteachers were also acting as security guards to stop “undesirables” entering playgrounds, and carrying out menial duties such as mopping flooded toilets and loading rubbish into skips.

“One of the most worrying concerns for heads was health and safety,” said the study, by leading educationalists from Cambridge, Edinburgh and Glasgow universities.

“Many of the routine tasks which they undertook, it was claimed, were in breach of rules and were accomplished because janitors were not allowed to undertake them. Heads were aware that such actions could also land them in trouble because they cut across union agreements. Often heads discovered by increment and accident their accountability for anything that happens within the school site, even though the school grounds may provide a public thoroughfare and venue for young people whose sometimes dubious night-time activities left health hazards.”

The report added: “These tasks were taken on because they felt that there was nobody to whom to delegate them and because, at the end of the day, it was heads who saw themselves as accountable for ensuring that they were attended to.”

The Scottish government-commissioned paper also revealed that many heads felt they were prevented from carrying out duties by “petty” local authority bureaucracy and “spurious ... political correctness”.

Examples of council box-ticking included requiring heads to get authorisation to repair broken windows, paint over graffiti or plant flowers at school.

Professor John MacBeath, chair of educational leadership at Cambridge University and lead author of the report, said he had heard a number of “heart-rending” accounts from frustrated headteachers.

The study, Recruitment and Retention of Headteachers in Scotland, found 57% of heads were “dissatisfied” or “very dissatisfied” with government policies and a third felt they had “very little autonomy”.

Some 66% of heads worked more than 50 hours a week, while a small minority clocked up more than 80 hours. The report made recommendations for greater autonomy and support for senior school staff.

MacBeath said most headteachers did not want to leave the profession. “Although some of them are very angry, these are highly dedicated professional people,” he said. “They wouldn’t be working 60-odd hours a week if they weren’t completely committed to doing the very best job.”

Ken Cunningham, of School Leaders Scotland, which represents more than 600 headteachers and deputy heads, said: “Headteachers regard the safety of their staff and pupils as a paramount priority and, unfortunately, this does bring them into these kinds of dangerous situations. They will not walk away, but we strongly advise them to take every precaution.”

Fiona Hyslop, the education secretary, said she would respond to concerns raised in the paper, which was commissioned in 2007 to investigate the lack of high-quality candidates applying for leadership roles in schools.

“This report highlights the pressures [headteachers] experience,” she said. “We need to ensure they are properly supported and developed to help them thrive and encourage more teachers to see the benefits senior positions offer.”

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