Employers are not doing enough to combat stress amongst their staff, the TUC has said.
Brendan Barber wants tough action on safety
The union made the claim following its annual survey into health and safety standards at work.
More than half TUC health and safety representatives said that their work colleagues were suffering from stress, a slight increase on last year.
In addition, cases of back ache and repetitive strain injuries (RSI) have also increased, the survey found.
Less than six out of 10 said they were happy with the risk assessments given, while nearly one in 10 representatives said that their employer had failed to carry out any assessment.
Other safety concerns raised included long hours, violence in the workplace and the use of display screen equipment.
"A simple risk assessment involving the expert guidance of trade union safety reps could dramatically reduce the risk of hazards in most workplaces," said Brendan Barber, TUC general secretary.
"The Health and Safety Executive must get tougher with negligent bosses who continue to be reckless with the safety and well-being of their workforce."