Twenty years of mercury monitoring in dental surgeries.

From 1981 to 2001 disposable mercury monitors based on palladium chloride have been deployed in 3,568 dental surgeries throughout the United Kingdom. They have performed well as first-level indicators of high concentrations of mercury vapour in surgeries that had become contaminated by spillage of mercury or faulty equipment. Whilst accumulated data suggests that mercury hygiene practices have improved over the past 20 years, the move to the use of disposable capsules rather than automatic amalgamators does not appear to have been a major factor in this improvement.