Irritant contact dermatitis due to 1-bromo-3-chloro-5,5-dimethylhydantoin in a hydrotherapy pool. Risk assessments: the need for continuous evidence-based assessments.

A physiotherapist working in hydrotherapy presented to occupational health with irritant contact dermatitis. Subsequent investigation revealed that the likely causative agent was 1-bromo 3-chloro 5,5 dimethylhydantoin which was used to disinfect the hydrotherapy pool. A COSHH risk assessment had been performed which failed to take full account of current knowledge and this agent had been introduced into the workplace. The development of adverse health effects among staff and other pool users lead to a review of this risk assessment and eventually a return to less hazardous chlorine-based disinfection. Had an evidence-based approach been combined with an appropriate COSHH assessment prior to and following changes in the workplace then unnecessary risk to employees would not have occurred.