Tobacco Worker’s Lung and Its Rehabilitation

Introduction:

Many industrial processes produce airborne contaminants, which the workers may inhale. As a result, many occupational diseases and problems arise from contact with airborne pollutants. Agricultural dust, cotton, flax, hemp, grains, and tobacco, when inhaled as aerosols, may cause harmful effects on the airways and lungs. For example, tobacco dust contains bacteria, endotoxins, fungal spores (mold), pesticides, and insecticides, causing tobacco workers' lungs. The management of tobacco workers' lungs is similar to the farmer's lung, which includes oxygen therapy, medications, and pulmonary rehabilitation.

What Is Tobacco Worker's Lung?

Tobacco worker's lung or tobacco grower's lung is a chronic type of hypersensitive pneumonitis (an allergic reaction causing inflammation in the lungs) or extrinsic allergic alveolitis affecting workers in the tobacco production industry exposed to tobacco leaves and molds (increased humidity in industry favors mold growth) dispersed in the air. It is categorized under the group of parenchymal lung diseases. Workers who do not use masks during the working period and who have been in the field for more than ten years are at higher risk of developing this disease.

How Do Worker's Get Exposed to Tobacco Dust?

Some of the standard occupational and environmental exposures associated with tobacco farming include the following.

1. Organic and inorganic dust exposure during harvesting.

2. Organic dust from leaves during sorting and packing the leaves.

3. Exposure to pesticides or insecticides during chemical spraying.

4. Exposure to tobacco dust while curing tobacco (use some fuels like wood to heat dry tobacco).

5. During cultivation, people are exposed to organic and inorganic dust to a greater extent. The source of organic dust is the dried tobacco leaves.

6. Workers are exposed to inorganic dust from field soils during fieldwork, usually silica.

7. The workers are also exposed to nicotine (a chemical produced by the tobacco plant) and pesticides to control diseases and parasites during cultivation. The most commonly used chemicals associated with respiratory effects include neonicotinoids containing acetamiprid, imidacloprid, and thiamethoxam; pyrethroids containing cyhalothrin and deltamethrin; herbicides containing active chemicals such as trifluralin and metolachlor; organophosphates containing dimethoate and chlorpyrifos.

What Is the Pathophysiology of a Tobacco Worker's Lung?

Tobacco workers' lung occurs due to the inhalation of an antigen (organic dust), which causes an exaggerated immune response. The suspected antigen is the fungus Aspergillus species. Therefore, the pathogenesis of a tobacco worker's lungs depends on immune mediation. Serum antibodies are present in most patients with tobacco workers' lungs causing clinical presentation in the pulmonary (lung) parenchyma. But the relationship between serum antibodies and pulmonary symptoms is still not clear.

What Are the Clinical Features of Tobacco Worker's Lung?

The clinical presentation of tobacco workers' lungs is similar to that of hypersensitivity pneumonia and has acute, subacute, and chronic symptoms. The symptoms are

• Acute Presentation - The abrupt onset of fever, chills, cough, muscle pain (myalgia), and headache occurs within 4 to 6 hours of exposure to tobacco dust or molds. These symptoms are self-limiting and resolve within 12 hours but recur with re-exposure.

• Subacute Presentation - This occurs when workers have a low level of contact with dust. The clinical presentation starts with fever, tiredness, coughing, and shortness of breath, and recurrent pneumonia occurs over time. This type gets worse with time.

• Chronic Presentation - This clinical presentation occurs after prolonged contact with dust. The symptoms are tiredness, shortness of breath, cough, weight loss, permanent lung scarring (pulmonary fibrosis), tachypnea (faster breathing), wheezing, digital clubbing (round-shaped abnormal nailbed), evidence of cor pulmonale (failure of the right side of the heart due to increased blood pressure in lung arteries), and diffuse fine rales (clicking or rattling sound in lungs when a person breathes in).

How to Diagnose Tobacco Worker's Lungs?

The following are the diagnostic procedures used to detect tobacco workers' lungs.

1. Spirometry - This test is used to detect pulmonary function. It uses digital ultrasonic flow measurement technology.

2. Allergy blood tests - A blood sample is collected and tested in the laboratory to detect the signs of reaction to the allergens.

3. Chest X-rays and Computed Tomography (CT) Scans to detect lung damage.

4. Bronchoscopy - A small flexible tube is inserted through the nose or mouth to detect lung damage and collect samples.

What Is the Treatment for Tobacco Worker's Lung?

The primary treatment strategy is the elimination of tobacco molds or leaves exposure and preventing further exposure to the antigens. The treatment options for tobacco workers' lungs include the following.

Medications - Corticosteroids or immunosuppressive medications, such as Prednisone, Mycophenolate, and Azathioprine, reduce inflammation. Antifibrotic drugs such as Pirfenidone and Nintedanib slow lung scarring.

Oxygen Therapy - Patients with troubled breathing need extra oxygen through tubes and masks. It provides oxygen to help with breathing. The various equipment used is standard oxygen concentrators, portable oxygen concentrators, liquid oxygen tanks, and compressed oxygen gas tanks.

Pulmonary Rehabilitation - The primary goal of respiratory or pulmonary rehabilitation is to help people maintain their independence and respiratory functioning. It improves the quality of life by

• Reducing shortness of breath.

• Increasing exercise tolerance.

• Decreasing the number of hospital stays.

• Promoting patient's well-being.

The rehabilitation program is provided by physical therapists, nurses, doctors, dieticians, and psychologists. The significant components of pulmonary rehabilitation include the following.

• Exercise Training - Reduces the shortness of breath and increases the ability to exercise. Aerobic exercises, walking, cycling, strength training, and exercise of arms and legs are the preferred activities to improve lung function.

• Inspiratory Muscle Training - It is used in association with aerobic exercises. Breathing exercises and devices are used to strengthen the muscles involved in breathing.

• Education about proper usage of drugs.

• Psychosocial Counseling - Shortness of breath may cause anxiety and depression. Counseling and group therapies help patients overcome depression.

• Neuromuscular Electrical Stimulation - A device that applies electrical impulses through the skin to selected muscles to stimulate contraction.

• Patients with pulmonary fibrosis may require a lung transplant.

• People at high risk of exposure to tobacco dust and molds in the workplace should wear personal protective equipment (PPE) and masks that filter small particles.

Conclusion:

Patients diagnosed with tobacco worker's lung should make a rehabilitation plan with healthcare providers. Medications and physical or breathing exercises advised by them reduce further lung damage and improve lung function. It is better to take preventive measures in the workplace as the damage caused to the lungs is irreversible.