Health and Safety
Executive / Commission
Freedom of information
1.1 This document contains advice following exposure or suspected exposure to asbestos from work activities. People who may have been exposed to asbestos are understandably anxious and concerned about possible effects on their health.
1.2 Inhalation of asbestos fibres can eventually lead to a number of diseases, including:
1.3 Asbestosis and bronchial carcinoma in particular are more clearly linked to high exposure for long periods. There is usually a long delay between first exposure to asbestos and the first symptoms of disease; this can vary between 10 and 40 years, with mesothelioma having a particularly long latency.
1.4 Much of the current burden of asbestos-related disease (about 4000 deaths per year) is a result of past heavy industrial exposures among those who manufactured and installed asbestos products. HSE is now primarily concerned about potentially frequent and regular exposure patterns arising from direct work with asbestos containing materials (ACMs), e.g. during maintenance activities. Such exposures could, over time, lead to a substantial accumulation of fibres in the lungs of some workers.
1.5 We are all continuously exposed to a low level of asbestos fibres because asbestos was such a widely used material within buildings, machinery, vehicle brakes and homes until 1999, when most forms of asbestos were banned. The aim of the Control of Asbestos Regulations 2006 is to prevent or reduce additional work-related exposure to asbestos fibres. However, working directly with asbestos containing materials (ACMs) can give personal exposures to airborne asbestos that are much higher than environmental levels. Repeated exposures of this type will give rise to a substantial cumulative exposure, thereby increasing the risk of developing an asbestos related disease in the future.
1.6 It is unfortunately not uncommon for people to be inadvertently exposed to asbestos fibres during building operations, maintenance work or following damage to asbestos-containing materials. Such incidents understandably cause anxiety about the possible effects, both short and long term, of the exposure. Workers subject to such exposures may consult their GP for advice, and may have unrealistic expectations regarding medical investigations or even treatment. There is at present no effective post-exposure prophylaxis for the effects of inhaled asbestos fibres, although in smokers the risk of asbestos-induced bronchial carcinoma (but not mesothelioma) can be reduced by stopping smoking. There are also no generally available techniques for determining individual lung burdens of asbestos fibres, other than post mortem.
2.1 It is often difficult to accurately relate specific asbestos exposures to an increased risk of developing disease in the future. The degree of risk will depend on the total life time cumulative exposure; the type of asbestos involved and the time elapsed since the person was first exposed. The degree of cumulative exposure is dependent on the amount of fibres that are generated by the work activity and how long it lasts. The concentration of fibres in the air will be determined by the force used and extent of the disturbance as well as the ability of the ACM to release fibres. The following are examples of work activities likely to create a significant concentration of fibres in the air and hereby add to the risk of developing an asbestos related disease:
2.2 The pattern of exposure to asbestos is a significant factor in determining the degree of risk. The following examples illustrate the main patterns of exposure and their relative risk:
3.1 Asbestos-induced radiological changes have a latency almost as long as that for symptom development (ie many years) and therefore a chest X-ray in the early aftermath of even heavy exposure is most unlikely to serve any useful purpose other than acting as a baseline. Similarly, periodic chest X-rays following an inadvertent exposure episode will serve little if any useful purpose in most cases, not least because in the vast majority of cases asbestos-induced disease is irreversible and untreatable by the time it can be diagnosed. However, a holistic view should be taken; clinical judgement may be that in some circumstances a chest X-ray may be of value where there is severe anxiety following asbestos exposure, and that the benefits of this may outweigh the very low level of risk associated with diagnostic X-ray exposures. In such circumstances the benefits and limitations of undertaking a chest X-ray should be explained carefully to the subject.
4.1 Further advice on cases of this nature can be obtained from chest physicians with an interest in occupational lung diseases and from medical inspectors of HSE's Employment Medical Advisory Service, who can be contacted via HSE’s central advice point Infoline, Tel: 0845 345005.
Revised April 2008