Occupational Asthma

This is an exerpt from a power-point presentation I recently gave on occupational asthma. This type of asthma should be regarded as different from 'ordinary' asthma that is made worse by one's workplace; true occupational asthma is actually caused by specific respiratory sensitisers in the workplace and may have severe financial implications for the employee who develops the disease.

Asthma UK, a charity dedicated to asthma states that there are 3,000 new cases of occupational asthma annually in the UK.

Asthma covers a range of symptoms: wheeze, cough, shortness of breath and tight chest.  It is brought about by an exaggerated immune response to an allergen (respiratory sensitiser).  When the allergen enters the body of someone prone to asthma, larger then normal amounts of Immunoglobulin E (IgE) are released.  This IgE causes the exaggerated immune response in the body, giving rise to inflammation and bronchoconstriction (narrowing) of the airways.  Treatment of asthma is aimed at reducing this inflammation and constriction - click here to find out how to prevent asthma.

 Occupational asthma is caused by sensitisation to an allergen in the workplace.  The Health and Safety Executive produce a list of common respiratory sensitisers; there are  currently 200 items on list, which is growing all the time, but there are some common allergens that frequently cause asthma:

Colophony - from pine resin, found in solder, glues and some floor cleaners

Flour/wheat

Isocyanides - found in paint sprays, adhesives, surface coatings and foundry cores.

Wood dust - especially red cedar

Animal and insect dander

Latex

The NHS Choices site states that "evidence suggests that those who remain in contact with an allergen for more than 1 year have significantly worse asthma."  So we can see how important it is to obtain an accurate diagnosis and treatment.

Occupational asthma should be suspected if an individual has:

Asthma symptoms that are worse at or after work. The allergic response may take time to build up, so the individual may be OK at work, but suffer later in the evening.

Asthma symptoms that cause disturbed sleep on work nights.

Asthma symptoms that improve at weekends or when on holiday.

Occupational asthma should be strongly suspected if asthma symptoms improve when a person is away from the workplace. The best diagnostic test is to record serial Peak Expiratory Flow Rates (PEFR) four hourly over a period of two weeks, which will give the asthma nurse, or doctor a clear picture of the illness. These tests are simple to do and involve the patient blowing into a PEFR metre and recording the value in a booklet.

Initially, an individual may have symptoms of itchy nose and eyes, blocked nose, sneezing, runny nose and eyes rather than asthma (conjunctivorhinitis). The health professional should take careful note of this, as it is often a precursor for occupational asthma.

Once occupational asthma is diagnosed, the individual should be referred to a chest or occupational physician, to confirm diagnosis and (if possible) work out what specifically the person is allergic to in the workplace. Early detection and treatment of the disease improves outcomes for the patient.

 The employer has a legal responsibility (under the Control of Substances Hazardous to Health COSHH Guidelines 1994) to remove respiratory sensitisers from the workplace and work colleagues have a legal responsibility not to expose you to respiratory allergens.

So the employer may need to:

 Install extractor fans/ fume cabinets

Provide breathing apparatus

Provide alternative chemicals for the same job

Relocate you to another job

Often a combination of these approaches is required

If you need to leave your job, inform your manager, your union and your GP, as you may need to make a claim from the Department of Work and Pensions: Disablement Benefit – currently £20 to £100 per week.

The financial burden on the individual may be great, and some individuals may have to remain working in contact with the allergen and suffering the consequent risks to health, because they can afford no alternative. The following is a snippet from a research article on the occupational asthma website that looks at outcomes of occupational asthma and work:

AmeilleJ, Paten JC, Bayeux MC et al: “consequences of occupational asthma on employment and financial status: a follow up study”

Three years after diagnosis:

44% of patients had left that job

25% of patients currently unemployed

32% remained exposed to the sensitiser

46% suffered a reduction of income

6 years post diagnosis 1/3 of workers remained unemployed.

Authors conclude that asthma “results in severe socio economic consequences”

There is less information about this, but we can assume some costs to the employer and nation:

The employer may have to moderate the work environment to make it acceptible to the person affected by occupational asthma.

The employer may carry out risk assessments, or may need to employ someone to do this for them.

There may be costs involved when buying new equipment.

There may be costs involved when redeploying individual to another department, or to retrain them.

There are costs involved when an employee takes of time off sick, both to the work place and national in lost production and benefits.

The employer may need to introduce pre-employment screening

Nationally there may be costs involved in Disablement Benefit

There may also be high costs of treating the individual with lifelong occupational asthma, as once sensitised to an allergen, the individual is likely to remain sensitive to it and may well suffer flare ups of their asthma when in contact with it.

 The British Occupational Health Research Foundation (BOHRF), a grant awarding charity that supports research into factors affecting mental and physical wellbeing in people at work sums the effects of occupational asthma up well:

“Occupational asthma presents in many ways.  It is often difficult to achieve good outcomes for the individual worker and the workplace.”