She told a Trades Union Congress (TUC) conference that bullying can have damaging long-term consequences for the health of victims, far outlasting employment with a particular company.

Tessa Jowell: Bullying can be bad for your health

Ms Jowell announced public funding for a new information pack to help doctors identify work-related illness and provide better treatment.

An estimated five million people have been or are bullied at work, according to figures from the TUC.

The organisation believes that the financial cost is huge, with around £4bn lost to industry as victims take time off work.

According to the TUC report, bullying is too often regarded as an occasional problem between individuals despite intimidation being regular and persistent.

Many organisations accept bullying as part of the culture or even encourage it, the TUC says.

One in 10 suffer

In the NOP survey for the TUC, 11% said they are being bullied or have been in the past and more than a quarter said they knew someone who was a victim.

Bullying is widespread throughout the country, the report says, with professionals and managers bearing the brunt of the intimidation.

While a tenth of skilled workers and 9% of unskilled workers reported bullying, 15% of professionals said they had been victims.

John Monks: "Shocking figures"

John Monks, the TUC's general secretary, said: "These shocking figures highlight the need for protection against bullying at work.

He said legislation proposed in the government's Fairness at Work White Paper will give employees the right to have a union official with them when they complain to their employer.

The TUC is already offering victims a 24-hour information hotline.

Bullies are "inadequates"

Tim Field: bullies are inadequates driven by envy

Tim Field, the founder of the National Workplace Bullying Advice Line, says workplace victims are picked on by their bosses because they are good at their jobs and popular with their colleagues.

Bullying bosses are "deeply inadequate and driven by jealousy and envy," he said.

"In the workplace it is somebody who is popular who is picked on, while at school it tends to be the child who is unpopular, but the character of the bully is the same.

"Far from pushing people hard to create results, these bosses actually prevent employees from doing their jobs."

Policies with teeth needed

Neil Crawford, a psychotherapist with the Tavistock Clinic, warned that companies tackling the problem needed to act with more than words.

"If they have a policy they need to think carefully about how they're going to implement it. Unless it has teeth, it is useless.

"The majority of people who are bullied, stay silent, never speak and just leave the organisation, therefore exit interviews are crucial."

A 1995 study by white collar union MSF found that only a quarter of employers had measures in place to tackle bullying.