Occupational diseases: overview and prevention

Occupational diseases are illnesses caused by workplace exposures and arising from occupational risk factors such as chemical agents, physical exposures, biological factors, and ergonomic stress. They differ from accidental illnesses by their established causal relationship to work, which influences prevention, treatment, and legal compensation issues. [1]

International organizations define occupational health as maintaining the highest possible level of physical, mental, and social well-being for workers in all occupations. This encompasses not only injury prevention but also systematic work to prevent work-related illnesses at all stages—from risk assessment to monitoring and medical supervision. [2]

To standardize the recognition of causality, the International Labour Organization's List of Occupational Diseases is used, which states are encouraged to use as a model when developing national lists. The latest revised version was adopted in 2010 and is accompanied by guidance notes on diagnostic and exposure criteria. [3]

Despite advances in occupational safety and health, the burden of occupational diseases remains significant for workers, businesses, and economies. Current strategies are shifting the focus from responding to consequences to preventing risks and improving the working environment. [4]

Epidemiology and burden

Official statistics record millions of cases of occupational injuries and illnesses annually, but a significant portion of these illnesses remain underdiagnosed due to latency, diagnostic uncertainty, and inadequate reporting. Different countries use different methodologies, making direct comparisons difficult. [5]

For example, the U.S. Bureau of Labor Statistics' 2023 reports estimated 2.6 million nonfatal injuries and illnesses in the private sector, highlighting the scale of occupational risks even with effective occupational safety programs. The data is updated annually with the publication of detailed summaries. [6]

There are significant industry differences: musculoskeletal disorders, stress, and mental health disorders, as well as respiratory and skin diseases, are more frequently reported. According to European sources, a significant proportion of low back pain is work-related, and some deaths from malignant tumors are associated with occupational exposures. [7]

Enterprise registers and surveys also show increased attention to psychosocial risks, climatic factors, and combined exposures. This requires updating prevention programs and regularly reviewing priorities at the enterprise and industry level. [8]

Classification

Occupational diseases are conveniently classified by the type of harmful factor: chemical, physical, biological, ergonomic, and psychosocial. Within each group, specific nosologies are identified with typical occupational exposure scenarios, facilitating diagnosis and prevention. [9]

An alternative approach is based on the affected organ system: respiratory system, skin, musculoskeletal system, hearing organs, nervous system, cardiovascular system, and oncological diseases caused by occupational carcinogens. This approach helps organize medical screening and monitoring. [10]

At the national level, disease lists are adapted to the local industry structure and evidence base, but are based on international guidelines. Regular revision of such lists is a key element in maintaining the legal recognition of cases. [11]

Many diseases are associated with multiple risks, where chemical and physical factors act simultaneously, and ergonomic loads enhance the effect. This complicates attribution, so comprehensive exposure criteria and a thorough occupational history are essential. [12]

Table 1. Main groups of occupational diseases and examples

Risk group	Examples of diseases	Typical sources
Chemicals	Chronic solvent intoxication, occupational asthma, contact dermatitis	Varnishes, dyes, isocyanates, metals
Physical	Sensorineural hearing loss, vibration disease, heat stress	Noisy workshops, hand tools, hot production
Biological	Zoonotic infections, tuberculosis in healthcare workers	Contact with patients or animals
Ergonomic	Muscle and joint disorders, back pain	Weight lifting, static poses
Psychosocial	Stress, depression, burnout	High load and low control

Collection of international lists and guidelines. [13]

Causes and risk factors

Chemical exposures include gases and aerosols, solvent vapors, metals, pesticides, and allergens that can cause toxic, irritant, and sensitizing effects. The risk depends on the concentration, duration, route of exposure, and individual susceptibility. [14]

Physical factors include noise, vibration, ionizing and non-ionizing radiation, extreme temperatures, and high pressure. Long-term exposure to noise increases the risk of hearing loss, and localized vibration is associated with anhidrosis, paresthesia, and vascular phenomena of the hands. [15]

Biological factors are important in healthcare, agriculture, veterinary medicine, and laboratories. They include viruses, bacteria, fungi, and parasites, as well as bioaerosols and endotoxins that cause infectious and allergic diseases. [16]

Ergonomic and psychosocial risks associated with repetitive motions, static postures, heavy lifting, high mental strain, and low autonomy increase the risk of musculoskeletal disorders, stress-related conditions, and decreased productivity. [17]

Pathogenesis and mechanisms

Toxic agents cause cellular damage through oxidative stress, disruption of membranes and enzymatic systems, or through immune sensitization mechanisms with the development of asthma or contact dermatitis. Dose cumulation and combined exposures enhance adverse effects. [18]

Physical stress causes mechanical and sensory tissue damage, such as cochlear hair cell loss from chronic noise or microvascular damage from vibration. Heat stress alters thermoregulation and water-electrolyte balance. [19]

Biological agents trigger infectious processes or immune hypersensitivity reactions, manifesting as exogenous allergic alveolitis, occupational rhinitis, or asthma. The conditions of aerosol formation and the effectiveness of personal protective equipment are important. [20]

Ergonomic loads and psychosocial stress cause muscle imbalances, strain on tendons, facet joints, and intervertebral discs, as well as neuroendocrine changes that affect sleep, mood, and chronic pain. This combination of factors creates persistent pain syndromes. [21]

Clinical picture

The spectrum of symptoms depends on the factor and the target organ. Respiratory diseases typically present with cough, wheezing, and shortness of breath, with exacerbations associated with work shifts and improvement on weekends and vacations. Cutaneous forms are characterized by erythema, itching, cracks, and chronicity with continued exposure. [22]

When exposed to noise, patients report hearing loss, tinnitus, and difficulty understanding speech, especially in noisy environments. Vibration syndrome manifests as paresthesia, cold fingers, decreased tactile sensitivity, and vasospastic episodes. [23]

Ergonomic disorders include back, neck, and joint pain, morning stiffness, grip weakness, limited range of motion, and symptom associations with specific tasks or postures. Psychosocial risks are associated with stress, anxiety, depressive symptoms, and burnout. [24]

Oncological risks manifest themselves years or decades after exposure to carcinogens. In such cases, occupational markers in the medical history and the involvement of an occupational pathologist in attribution are particularly important. [25]

Diagnosis and confirmation of causality

Diagnosis begins with a detailed occupational history: profession, length of service, specific operations, materials and processes, environmental monitoring, and use of protective equipment. This is supplemented by a clinical examination and targeted laboratory and instrumental testing of the affected organ. [26]

To confirm causality, guidance notes to the International Labor Organization list of diagnostic and exposure criteria for various nosologies are used, taking into account latency periods, exposure thresholds, and typical clinical and laboratory features. This increases the transparency of decisions and legal certainty. [27]

Instrumental methods include audiometry in noise, spirometry and provocative tests in asthma, dermatological tests in contact dermatitis, imaging and electromyography in musculoskeletal disorders. If friction and chemical exposures are suspected, biomarkers and hygiene measurements are important. [28]

Complex investigations utilize hazard assessment teams, such as the National Institute for Occupational Safety and Health's Health Hazard Assessment Program, to help identify and address occupational hazards. This expedites the translation of findings into actionable measures. [29]

Table 2. Diagnostic route

Step	Content	Target
Professional history	Position, operations, materials, modes	Identify probable factors
Clinical evaluation	Examination, symptom profile, shift communication	Specify the target organ
Laboratory and instrumental tests	Audiometry, spirometry, skin testing, visualization	Objectify the damage
Exposure assessment	Hygienic measurements, risk documents	Confirm contact and levels
Attribution	International Labour Organization criteria and national regulations	Make a decision and plan of action

Summary of clinical and regulatory guidelines. [30]

Differential diagnosis

In each case, it is necessary to exclude non-occupational causes with similar symptoms: household allergens, smoking, age-related hearing changes, systemic inflammatory diseases, and metabolic disorders. This prevents overdiagnosis and helps focus prevention. [31]

Particular difficulties arise in oncological diseases, where proving a causal relationship requires taking into account cumulative exposure, latency period, and other risk factors. Interdisciplinary consultations and the use of epidemiological data are essential here. [32]

In musculoskeletal disorders, acute injuries and degenerative changes must be distinguished from overuse disorders associated with specific tasks and postures at the workplace. Symptom diaries and workflow analysis assist in this distinction. [33]

In the field of infectious diseases, community outbreaks are differentiated from occupational cases based on contact tracing, biological markers, and analysis of transmission routes in the occupational environment. [34]

Treatment and management

Treatment combines standard clinical therapy for the specific disease and mandatory elimination or reduction of occupational exposure. Without changes in working conditions, drug treatment often produces an incomplete effect and a high risk of relapse. [35]

The risk management strategy is built on a hierarchy of measures: hazard elimination, substitution, engineering solutions, administrative measures, and personal protective equipment. Priority is given to the first three levels as the most reliable in terms of prevention. [36]

Once the diagnosis is confirmed, medical monitoring, rehabilitation, patient self-management training, and temporary work restrictions are arranged. For some conditions, early return-to-work programs with task adaptations are used. [37]

In the case of cluster cases and outbreaks, an investigation is conducted involving the employer, workers, and regulatory authorities, the risk assessment and action plan are adjusted, and staff training is updated. This reduces the risk of recurrence. [38]

Table 3. Hierarchy of risk management measures

Level	Example for chemical factor	Example for ergonomic factor
Elimination	Avoiding toxic fumes	Elimination of manual lifting operation
Substitution	Less volatile solvent	Effort-reducing equipment
Engineering solutions	Local exhaust ventilation	Lifts, conveyors, adjustable tables
Administrative measures	Shift rotation, regulations, breaks	Technique training, microbreak plan
Protective equipment	Gloves, respirators	Orthoses according to indications

Code of practice on occupational safety and health. [39]

Prevention and monitoring

Effective prevention relies on systematic risk assessment, worker participation, an action plan, and regular audits. Data on health and injury trends allow for the evaluation of the effectiveness of measures and the adjustment of priorities. [40]

Sector reviews by the European Agency for Safety and Health at Work highlight the need to take into account new and emerging risks, including climate impacts and psychosocial factors, which require integration into corporate management systems. [41]

At the national level, annual reports on illness and injury rates are published to help guide inspections and prevention campaigns. Public reporting of non-fatal cases and days of incapacity encourages businesses to improve. [42]

Businesses are advised to implement screening programs for priority risks, vaccination for at-risk groups, and training in early symptom recognition. This reduces the incidence of severe outcomes and improves return to work. [43]

Legal aspects and compensation

Recognition of a disease as occupational entitles one to compensation and special protection measures, but procedures vary between countries. National lists and criteria are based on international guidelines and are regularly reviewed. [44]

Employers are required to maintain records and reports on injuries and illnesses and provide access to data for regulatory authorities. Electronic platforms for submitting summary forms and event cards improve transparency and speed of analysis. [45]

Worker rights include access to risk information, participation in training, the right to safe working conditions, and the right to medical supervision for confirmed exposures. Joint safety committees strengthen a safety culture. [46]

Insurance and compensation mechanisms encourage prevention when linked to risk assessment results and health indicators at the enterprise. Reliable diagnosis and correct attribution are important for fair decisions. [47]

Forecast

The prognosis depends on the underlying disease, the timeliness of exposure cessation, and the quality of rehabilitation. With early detection and modification of working conditions, many conditions are reversible or achieve stable remission. Delays in changing exposure increase the risk of chronicity. [48]

Musculoskeletal disorders often improve with a combination of measures, including engineering solutions and core training. In occupational asthma, outcomes are better with early cessation of exposure to the sensitizer. For sensorineural hearing loss, prevention is paramount, as recovery is limited. [49]

Occupational oncological diseases require follow-up care and long-term rehabilitation. Proper attribution allows the family and worker to receive support and focus on treatment. [50]

Regular review of risk assessments and a continuous improvement program within the enterprise reduces repeat incidents and increases staff retention, which benefits both employees and employers. [51]

Frequently asked questions

• How can you tell if a disease may be occupational?

Consider whether symptoms are associated with work shifts, improvement on weekends and vacations, the presence of colleagues with similar complaints, and confirmed exposures. Discuss the occupational anamnesis with your doctor and the possibility of referral to an occupational therapist. [52]

• What are the most effective preventative measures?

The most reliable measures are those at the top levels of the hierarchy: hazard elimination, substitution, and engineering solutions. Personal protective equipment is important, but is not a substitute for process modification. [53]

• Where should I apply for an assessment of working conditions?

On-site workplace assessment and occupational health consultation programs are available to help identify and address hazards, such as the National Institute for Occupational Safety and Health's Health Hazard Assessments. Check with your country or region for availability. [54]

• Where can I find updates on trends and statistics?

Publications by the European Agency for Safety and Health at Work and national reports on injuries and illnesses make it possible to monitor emerging risks and evaluate the effectiveness of measures at the sectoral level. [55]