Occupational, or work-related lung diseases are conditions that have been caused or made worse by the substances employees have been exposed to and inhaled whilst at work.
The impact of these conditions is underestimated due to under-reporting, as some lung conditions occur later in life when the person is no longer at work but is related to a previous occupation.
It is estimated that as many as *15-20% of cases of Adult-Onset Asthma and *15% of Chronic Obstructive Pulmonary Disease (COPD) cases are connected to prior exposures within the workplace. (*Source: Work-related asthma statistics, 2023 - hse.gov.uk)
In Northern Ireland, there are estimated to be as many as **110 COPD deaths occurring each year that are due to past exposures at work. (**Source: Department for the Economy, NICS)
What are the symptoms of occupational lung disease?
Persistent coughing, as well as severe difficulties in breathing, are just two of the symptoms that sufferers of occupational lung diseases may have to deal with on a daily basis.
Symptoms can often be painful and debilitating, affecting the persons way of life and in severe cases can prevent sufferers from leading a normal lifestyle.
Other symptoms include:
shortness of breath
chest tightness
regularly coughing up mucus or phlegm
wheezing or noisy breathing
chest pain
coughing up blood
chronic mucus production
chronic fatigue
blue lips or fingernails
If you have concerns about your health, you should speak to your GP for advice.
Look at your trade or industry to get an understanding of the types of workplace health hazards there are and protect your employees and others against these health hazards.
Sector specific respiratory health information can be found on the Health and Safety Executive’s (HSE GB) website at the following link:
Occupational asthma is a type of lung condition that is triggered or made worse by exposure to substances within the workplace.
It occurs when a person, who has never suffered from asthma before, develops asthma-like symptoms (such as wheezing, shortness of breath, coughing, and chest tightness) due to inhaling allergens or irritants at their place of work.
The condition can either develop over time due to long-term exposure to certain workplace substances or can arise quickly following a single high-level exposure.
Causes and triggers:
allergens - such as dust, mould, or animal dander, often seen in jobs involving farming, animal care, or certain laboratory work
irritants- chemical fumes, gases, or vapours in industries like manufacturing, cleaning, construction, and welding
sensitizers - substances that cause an immune response leading to asthma - common examples include:
persistent cough, especially at night or early morning
chest tightness
increased mucus production
Occupational COPD
Occupational COPD refers to a form of chronic lung disease that is caused or worsened by exposure to harmful substances in the workplace. Like other forms of COPD, it is characterised by persistent airflow limitation and difficulty breathing, but in this case, the underlying cause is related to work-related factors, such as inhalation of dust, fumes, gases, or chemicals.
Causes and risk factors
Occupational COPD is primarily caused by long-term exposure to inhaled irritants in the workplace. Some of the common exposures that can contribute to the development of COPD include:
Dust:
coal dust (common in mining or construction)
silica dust (common in industries like stone cutting, construction, or quarrying)
grain dust (common in agriculture or grain handling)
cotton or textile dust (common in textile manufacturing)
chemical vapours (from industries such as plastics, paint manufacturing, or chemical production)
vehicle exhaust fumes (in certain transportation and maintenance jobs)
Gases:
Nitrogen dioxide (from industrial activities)
Ozone (in certain work environments like industrial welding or cleaning)
Workers who smoke and are also exposed to occupational air pollutants are at higher risk for developing COPD.
Jobs involving long-term exposure to environmental irritants, such as farming, metalworking, or even some healthcare settings (due to disinfectants or cleaning agents), may also be at increased risk.
Symptoms of occupational COPD
The symptoms of occupational COPD are similar to those of non-occupational COPD and include:
chronic cough (often with sputum production)
wheezing
shortness of breath (especially with physical activity)
chest tightness
fatigue due to reduced lung function
These symptoms tend to worsen over time as exposure continues. Many people with occupational COPD have a history of working in environments with high levels of harmful dust, gases, or fumes for many years.
Silicosis
Silicosis is a type of pneumoconiosis, which is a group of lung diseases caused by the inhalation of different types of dust.
Specifically, silicosis is caused by inhaling respirable crystalline silica dust - a common mineral found in materials like sand, rock, concrete, and mortar. Silica dust is often generated during activities like mining, construction (for example, drilling, grinding, or sandblasting), stone cutting, and other industries that involve working with materials containing silica.
Types of silicosis
Silicosis can be categorised into three main types, based on the duration and intensity of exposure:
Chronic silicosis:
the most common form, occurring after long-term exposure (usually 10 years or more) to low to moderate levels of silica dust
it often develops slowly and may not show symptoms until after years of exposure
symptoms include shortness of breath, persistent cough, and fatigue
Accelerated silicosis:
occurs after five to ten years of exposure to higher levels of silica dust
it progresses faster than chronic silicosis and can lead to more severe lung damage
symptoms may appear quicker than in chronic silicosis and worsen over time
Acute silicosis:
caused by short-term, intense exposure to very high levels of silica dust, such as during a sandblasting operation or other activities where large quantities of dust are generated quickly
it develops rapidly, often within weeks to a few years of exposure
symptoms are severe and include difficulty breathing, cough, and severe lung damage that can be fatal
Symptoms of silicosis
Symptoms can develop gradually, especially in chronic silicosis, and may include:
chronic cough (often with sputum production)
shortness of breath, especially with physical activity
fatigue
chest pain or discomfort
wheezing or a feeling of tightness in the chest
loss of appetite and weight loss in advanced stages
Pneumoconiosis
Pneumoconiosis is a general term for a group of lung diseases caused by the inhalation of various types of dust or particulate matter in the workplace. These particles can irritate the lungs, leading to inflammation, fibrosis (scarring), and impaired lung function.
The condition is most often associated with long-term exposure to dusts found in certain occupations, such as mining, construction, and manufacturing.
The key characteristic of pneumoconiosis is the damage caused to the lungs by inhaling harmful dust particles over time. The severity of the disease depends on the type of dust, the duration and intensity of exposure, and individual susceptibility.
Types of pneumoconiosis
There are several well-known types of pneumoconiosis, each caused by specific types of dust:
Coal Workers' Pneumoconiosis (CWP) or Black Lung Disease:
caused by inhaling coal dust, typically in mining or processing coal
the inhalation of coal dust leads to the accumulation of carbon particles in the lungs, causing inflammation and fibrosis
there are two forms:
simple CWP - characterised by small, round nodules in the lungs
complicated CWP - involves larger, more extensive scarring and can lead to more severe respiratory impairment
Silicosis:
caused by inhaling crystalline silica dust, which is found in materials like sand, rock, quartz, and concrete
silicosis is particularly common in occupations like mining, stone cutting, sandblasting, and construction
there are three forms: chronic, accelerated, and acute silicosis, depending on the level and duration of exposure
Asbestosis:
caused by inhaling asbestos fibres, which were once widely used in construction, insulation, and manufacturing
asbestos fibres can cause severe lung scarring and increase the risk of lung cancer and mesothelioma (a rare cancer of the lining of the lungs and other organs)
asbestosis is progressive and can lead to severe difficulty breathing
Berylliosis:
caused by inhaling dust or fumes containing beryllium, a metal used in aerospace, electronics, and nuclear industries
this condition can cause inflammation and scarring in the lungs and is sometimes linked to an allergic or immune response
Byssinosis (also known as "brown lung disease"):
caused by inhaling cotton or textile dust, typically in cotton mills or textile factories
symptoms include coughing, chest tightness, and shortness of breath, and it can worsen over time if exposure continues
Siderosis:
caused by inhaling iron oxide dust, which is typically seen in workers in steel mills or metalworking industries
siderosis often causes mild to moderate lung damage but can be asymptomatic in early stages
Symptoms of pneumoconiosis
The symptoms of pneumoconiosis depend on the specific type of dust and the extent of lung damage but generally include:
chronic cough
shortness of breath, particularly with physical exertion
chest pain or tightness
fatigue
wheezing
sputum production (coughing up mucus)
clubbing of fingers (in advanced cases, where the tips of fingers become rounded)
Symptoms tend to develop gradually and may worsen over time, especially if exposure to the harmful dust continues.
Extrinsic Allergic Alveolitis
Extrinsic Allergic Alveolitis (EAA), also known as Hypersensitivity Pneumonitis (HP), is a lung condition caused by an allergic reaction to inhaled organic particles, typically dust, mould, or other allergens, which leads to inflammation of the alveoli (the tiny air sacs in the lungs where oxygen exchange occurs). This condition occurs when the immune system overreacts to these inhaled particles, triggering an inflammatory response in the lungs.
EAA is considered an interstitial lung disease (ILD), as it primarily affects the interstitial tissue (the tissue and space around the air sacs) in the lungs.
Causes and triggers of EAA
EAA is caused by the inhalation of various allergens or organic particles, which can be found in a variety of occupational and environmental settings.
Some common triggers include:
fungal spores, often found in mouldy hay, compost, or grain
bird droppings or feathers, common in bird breeders, farmers, or pet owners
bacterial spores, found in certain agricultural settings or in humidifiers
wood or vegetable dust - exposure to dust from wood, hemp, or tobacco can trigger EAA in some workers
animal dander - pet owners or workers in animal-related industries (like veterinary clinics or farms) may be at risk
pollen - in rare cases, certain types of pollen can cause EAA
Types of EAA
There are different forms of EAA, often based on the nature of exposure and the clinical presentation.
Acute EAA:
this form occurs after short-term, high-level exposure to an allergen
symptoms usually appear hours after exposure and include:
fever
cough
shortness of breath
chills
fatigue
muscle aches
these symptoms are often mistaken for a flu-like illness or pneumonia
acute episodes tend to improve with removal from the exposure, but repeated episodes can lead to chronic inflammation and lung damage
Chronic EAA:
chronic EAA develops after long-term, repeated exposure to lower levels of an allergen
over time, chronic inflammation leads to fibrosis (scarring) in the lungs, which can cause permanent lung damage
symptoms may include:
progressive shortness of breath, especially with exertion
dry cough
weight loss
fatigue
as the disease progresses, the damage to the lung tissue can lead to pulmonary fibrosis, a condition in which the lung tissue becomes stiff and scarred, impairing gas exchange
Symptoms of EAA:
The symptoms of EAA depend on the form (acute or chronic) and may include:
Acute symptoms:
fever
shortness of breath
dry cough
chills
chest tightness or discomfort
muscle and joint pain
fatigue
headache
These symptoms often occur four to eight hours after exposure to the triggering substance, and they tend to resolve if the person is removed from the source of exposure. However, if the exposure is repeated or prolonged, the condition can progress to the chronic form.
Chronic symptoms:
progressive shortness of breath, especially with physical activity
persistent dry cough
fatigue
unintentional weight loss
clubbing of fingers (in advanced cases, where the tips of the fingers become enlarged due to reduced oxygen levels)
wheezing or crackling sounds in the lungs
Preventing lung disease
When a substance or substances meets the definition of a ‘substance hazardous to health’ under the Control of Substances Hazardous to Health Regulations (NI) 2003 (COSHH NI), the employer is required by law to control exposures to such hazardous substances in order to protect employees' health:
A full risk assessment must be completed prior to using any substance or process to determine whether any substances hazardous to health are present or are likely to be generated by the process for example, fine sanding of some woods leading to airborne fine dusts etc. or paint spraying with isocyanates, handling animals etc.
Employers must then apply controls in the following order of priority:
design and operate processes and activities to minimise emission, release and spread of substances hazardous to health
take into account all relevant routes of exposure - inhalation, skin absorption and ingestion - when developing control measures
control exposure by measures that are proportionate to the health risk
choose the most effective and reliable control options which minimise the escape and spread of substances hazardous to health
where adequate control of exposure cannot be achieved by other means, provide, in combination with other control measures, suitable personal protective equipment (PPE) and/or respiratory protective equipment (RPE)
check and review regularly all elements of control measures for their continuing effectiveness
inform and train all employees on the hazards and risks from the substances with which they work, and the use of control measures developed to minimise the risks
ensure that the introduction of control measures does not increase the overall risk to health and safety
There are many things you can do as an employer to reduce the risk of occupational lung disease in your workplace.
assess the risks
apply the Hierarchy of Control:
elimination - physically remove the hazard
substitution - replace the hazard
engineering controls - isolate people from the hazard
administrative controls - change the way people work
PPE / RPE - protect the worker with personal protective equipment
provide health surveillance - see below
Health surveillance
Health surveillance means putting procedures in place to look for early signs of work-related ill health.
Health surveillance helps to:
Identify health problems early - so that actions can be taken to prevent the condition from worsening or becoming permanent
Monitor trends in the workforce’s health, which can provide valuable information for employers to improve workplace safety
Ensure compliance with legal obligations - employers are required to carry out health surveillance if certain risks are present
If health surveillance is required, it must be carried out by a qualified healthcare professional, and the employer must act on any findings to mitigate risks. The specific requirements are set out in COSHH NI and might involve examinations by a doctor or trained nurse.
HSE GB has produced simple guidance on what health surveillance is required in the following publication:
employees benefit by getting early detection and treatment if any work-related health conditions are identified
employers benefit by ensuring compliance with health and safety legislation, reducing workplace illnesses, and preventing long-term health problems that could lead to absenteeism or claims
Advice for employees
The key messages for employees are:
avoid breathing in and direct handling of hazardous substances
ask your employer if the necessary controls are in place and working
PPE / RPE must be supplied and maintained free of charge by the employer
employees must cooperate fully with the employer - including attending health surveillance appointments where necessary
