More than half of all secondary schoolteachers in England say their job is “unmanageable”, according to an international survey revealing that teachers in England have one of the highest workloads in the world.

The survey of teachers and school leaders in 48 countries conducted by the Organisation for Economic Cooperation and Development (OECD) makes depressing reading for those in the profession in England, who had longer working days than anywhere else other than Japan.

John Jerrim, professor of education and social statistics at UCL’s institute of education, said there had been a clear fall in job satisfaction since the last teaching and learning international survey, noting that more than half of secondary teachers said they may have been better to have chosen another career.

“Low levels of job satisfaction amongst secondary is clearly a serious problem in England, one that education policymakers need to urgently address,” Jerrim said in a commentary on the survey.

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One cause appeared to be the volumes of marking required by teachers in England, where, despite years of effort by successive education secretaries, the high proportion of teachers having to mark and write feedback for pupils remains unchanged since the previous survey in 2013.

Meanwhile, the average age of teachers in England is five years lower than the average age throughout the OECD countries, suggesting that large numbers continue to quit in the early stages of their career, and that those remaining were less experienced: secondary teachers had 13 years in the profession compared to an OECD average of 17 years.

Damian Hinds, the education secretary, endorsed the survey’s results, saying: “These findings reflect many of the frustrations that I heard from teachers and heads when I first took on the role of education secretary and underlines the importance of the teacher recruitment and retention strategy that I launched in January this year.

“We know that too many teachers are having to work too many hours each week on unnecessary tasks, which is why I have taken on a battle to reduce teachers’ workload so that they can focus on spending their time in the classroom, doing what they do best – teaching.”

While other countries have teachers with an average age of 44, those in England are on average 39 years old, with 18% remaining in the profession after the age of 50 compared with an average of 34% elsewhere.

One reason may be the OECD’s finding that younger teachers – those with up to five years’ experience – usually worked two hours longer each week than their more experienced colleagues, with 50% leaving before the end of five years.

The latest survey showed that many teachers working hours have got longer since the previous survey in 2013, from 48 to more than 49 hours a week for secondary school teachers. Primary school teachers in England recorded working 52 hours a week, longer than their peers in other countries apart from Japan.

Mary Bousted, joint general secretary of the National Education Union, said the survey of 4,300 teachers at 300 schools revealed a demoralised workforce.

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“The findings should act as a wake-up call for any future prime minister. The government must end teachers’ unsustainable workload by tackling the high-stakes school accountability system which is fuelling the long hours culture and driving teachers out of the profession,” Bousted said.

James Zuccollo of the Education Policy Institute (EPI) said: “This has serious implications for retention, at a time when too many teachers are quitting the profession early on in their careers, and the number of pupils in secondary schools is growing fast,” Zuccollo said.

England also stands out thanks to its weak proportion of women in senior leadership roles: while 64% of teachers in secondary schools are women, just 41% are headteachers, similar to France and Denmark but below most other countries.

The survey found that while regular incidents of vandalism, injury and abuse directed towards staff had all declined since the previous survey, headteachers reported a sharp increase in the number of weekly incidents of physical and verbal bullying among pupils, rising from 14% in 2013 to 29% in the latest edition.