96 Thoraxc 1996;51:96 96 Thorax 1996;51:96~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Occupational lung disease * Introduction Series editor: P S Burge

New developments in occupational lung disease Thorax: first published as 10.1136/thx.51.1.96 on 1 January 1996. Downloaded from

P Sherwood Burge

Occupational lung diseases are often thought of exposure in the workplace and development to be rare. A great breakthrough in the UK of disease, there is little evidence that oc- came with the introduction of SWORD, which cupational asthma is decreasing. She estimates suggests that they occur much more frequently that 4-8% of adult asthma is occupational in than many had thought. The SWORD vol- origin. There is substantial confusion as to untary reporting system for occupational lung whether asthma induced by irritant mech- diseases receives regular reports from oc- anisms is different from that induced by allergic cupational and respiratory physicians; noti- or unknown mechanisms. Professor Newman fication is based on occupation being the most Taylor reviews the role of respiratory irritants, likely cause for the disease, rather than spe- in particular whether there can be lasting cifying specific diagnostic conditions. Noti- asthma from single exposures. Professor Pick- fications do not have legal or regulatory ering reviews advances in byssinosis, regarded consequences which often impede statistics by some as a variant of occupational asthma, from other sources. SWORD has shown that and demonstrates the range of lung diseases diseases of the airways predominate, and as- related to cotton exposure. Several studies have bestos-related pleural disease is still very com- investigated the risk factors for the development mon. Several of the reviewers in this series of occupational asthma. The recent outbreak make use of the SWORD data. of environmental asthma due to unloading of Occupational lung cancer remains in- soya in Barcelona has presented an opportunity frequently diagnosed, however, as there are to investigate the risk factors in the general often no specific features in an individual to sep- population and these are reviewed by Anto. arate the occupational factors from tobacco The results show an amazing similarity with smoking. Exposure to silica has long been re- the risk factors in an occupational setting (re- cognised as a riskfactor for tuberculosis, and the viewed by Sarah Meredith), surprisingly show- series starts with a review by Weill and McDon- ing relationships with increasing age and http://thorax.bmj.com/ ald ofnew evidence on the relationship between smoking. exposure to silica and lung cancer which sug- Occupational asthma is one of the more gests that the relationship depends on the type difficult diagnoses that a chest physician has to ofsilica to which the worker is exposed. make. New help has come from the analysis of in serial measurements of lung function at home There have been real developments as- and at work, showing a successful application of bestos-related pleural disease, particularly in neural net technology to the problem of sep- relation to improved computed tomographic arating effects due to work from those due to (CT) scanning and more helpful wide window otherfactors such as diurnal variation, infection, on October 1, 2021 by guest. Protected copyright. settings which have identified substantially and other non-specific triggers. This is reviewed more diffuse pleural thickening than was pre- by Bright and Burge. As is so often the case, one viously recognised. The clinical and physio- finding is the requirement for better quality data logical correlates are analysed by Rudd, who than are commonly recorded. reviews new findings related to physical signs Not all chronic obstructive pulmonary dis- and lung function abnormalities found in ease (COPD) is caused by cigarette smoking. pleural disease. Many inorganic particles and It has been difficult, however, to separate the fibres are retained in the lung and can be effects of cigarette smoking from occupational estimated in lung tissue or bronchoalveolar effects because of the large number of workers lavage fluid. This can allow estimates to be who smoke. Good epidemiology, better es- made of historical exposure which may help to timates of smoking history and occupational clarify the relationships between exposure and exposure, and perhaps the use of job/exposure disease, particularly with regard to asbestos matrices have all helped. The role of oc- exposure. The methodological problems with cupational agents in the causation of COPD - such analyses and the interpretation of results likely to be an area of substantial growth in the are reviewed by Gibbs in the third article in next few years - is reviewed by Hendrick in the series. the final article in the series. This area continues The other reviews all relate to airways ob- to be handicapped by the definitions of ob- Department of struction. Sarah Meredith reviews the Respiratory Medicine, epi- structive airway diseases. Birmingham demiology of occupational asthma in four It is hoped that this review series will stim- Heartlands Hospital, countries from which there are reasonable stat- ulate clinicians to enquire into the occupational Bordesley Green East, istics and shows the effects of different con- of their which is often il- Birmingham B9 5SS, history patients, UK straints on notification. Despite our knowledge luminating. The series is short ofbasic science, P Sherwood Burge and a very short lead time between reduction for which I apologise.