Western red cedar
Occupational asthma due to Western red cedar dust is a very well recognised cause of occupational asthma and affects 4-13.5% of the exposed population.
It has been shown to be caused by plicatic acid (thuja plicata), a low molecular weight compound present in the wood.
The Oasys Audit scheme started midway through 2010 and collects agents typed in through the Oasys program. The years before 2010 show old data entered during 2010 or later and are likely to have many fewer notifications. We expect Oasys to become more widely adopted as time goes by so increasing notifications does not necessarily mean an increasing problem.