One case report of occupational asthma to polyproylene. Specific inhalation challenges using polypropylene heated to 250 degrees C resulted in a late asthmatic reaction.
Formaldehyde is one of the degradation products of heating polypropylene, so this needs to be tested for as well.
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.