Nearly all cases reported in 2010 were by the Birmingham Chest Clinic. We hope to increase the number notified by others this year by using the MTS website to contact notifiers.

The method of reporting to the Shield scheme has now changed and is done via the new version of the Oasys program that works through the internet. For those that use serial peak flows as a method of diagnosis this will greatly improve the ease of reporting. The data collected is all anonymous and so there are some changes in the data that we record, although it is still largely similar.

Hardly an outbreak but outbreak of the year is a histopathology laboratory with 2 works having occupational asthma from formaldehyde. The laboratory was unusual in that it specialised in amputated limbs which are obviously very large compared with normal histopathology specimens making formaldehyde exposure more difficult to control. The widespread use of cut-up tables with down draft ventilation has greatly reduced formaldehyde exposures in histopathology departments, but large objects (or cut-up slabs) reduce their efficiency. Some believe that formaldehyde is not a cause of occupational asthma. Since 1989 there are 33 notifications of formaldehyde asthma to Shield, including 4 from histopathology laboratories, 10 from foundries using phenol formaldehyde hot box systems for making cores, 3 from injection moulders of formaldehyde-based resins and 4 from chemical works manufacturing formaldehyde.

A 48 year old worker developed cough, sputum and wheeze 11 years after starting work where local water (ie not from the mains) was used to wet sand and clay and sprayed to reduce dust in hot weather. Serial PEF records showed intermittent occupational asthma. We wondered whether he had low-dose irritant induced asthma similar to a bricklaying lecturer who had a positive challenge to lime dust. The worker had a negative challenge to lime dust but a positive challenge to nebulised local water. Microbial contaminated water is a well recognised cause of occupational asthma, humidifier fever and allergic alveolitis from air humidification systems.

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