Occupational Environmental Lung Disease

Question 1

new associations between exposure and disease may be identified

Answer 1

nylon flock worker’s lung disease and diacetyl-induced bronchiolitis obliterans

Question 2

Exposures to inorganic and organic dusts can cause interstitial lung disease that presents with——

decreased diffusing capacity

Answer 2

restrictive pattern

Question 3

small rounded opacities

Answer 3

silicosis or coal worker’s pneumoconiosis

Question 4

small linear opacities

Answer 4

asbestosis

a history of asbestos exposure, conventional computed tomography (CT) is more sensitive for the detection of pleural thickening, and high-resolution CT (HRCT) improves the detection of asbestosis.

Question 5

Water- soluble gases

Answer 5

ammonia
dioxide

are absorbed in the lining fluid of the upper and proximal airways and thus tend to produce irritative and bronchoconstrictive responses

Question 6

Less water soluble

Answer 6

nitrogen dioxide and phosgene

may penetrate to the bronchioles and alveoli in sufficient quantities to produce acute chemical pneumonitis

Question 7

particles >10–15 μm in diameter

Particles <10 μm in size

Answer 7

diameter do not penetrate beyond the nose and throat

deposited below the larynx

Question 8

Particles ~2.5–10 μm (coarse-mode fraction)

Answer 8

contain crustal elements such as silica, aluminum, and iron

mostly deposit relatively high in the tracheobronchial tree

Question 9

particles <2.5 μm (fine-mode fraction)

Answer 9

toxic agents can deposit and be carried to the lower airway

fine particles are created primarily by the burning of fossil fuels or high-temper-ature industrial processes resulting in condensation products from gases, fumes, or vapors

Question 10

smallest particles, those <0.1 μm in size

Answer 10

ultrafine fraction and make up the largest number of particles; they tend to remain in the airstream and deposit in the lung only on a random basis as they come into contact with the alveolar walls

penetrate into the circulation and be carried to extrapulmonary sites

Question 11

ASBESTOS-RELATED DISEASESg

Asbestos: generic term for several different mineral silicates, includ-ing chrysolite, amosite, anthophyllite, and crocidolite

Answer 11

manufacture of fire-resistant textiles, in cement and floor tiles, and in friction materials such as brake and clutch linings.

Question 12

major health effects from exposure to asbestos

Answer 12

pleural and pulmonary fibrosis, cancers of the respiratory tract, and pleural and peritoneal mesothelioma

Question 13

diffuse interstitial fibrosing disease of the lung that is directly related to the intensity and duration of exposure.

Answer 13

Asbestosis

oxidative injury due to the generation of reactive oxygen species by the transition metals on the surface of the fibers as well as from cells engaged in phagocytosis.

thickening or calcification along the parietal pleura, particularly along the lower lung fields, the diaphragm, and the cardiac border.

Question 14

hallmark of asbestosis

Answer 14

Irregular or linear opacities that usually are first noted in the lower lung fields are the chest radiographic hallmark of asbestosis.

heart border or a “ground-glass” appearance in the lung fields may be seen

Pulmonary function testing in asbestosis reveals a restrictive pattern with a decrease in both lung volumes and diffusing capacity

Question 15

oldest known occupational pulmonary hazards,

Answer 15

free silica (SiO2), or crystalline quartz, is still a major cause of disease.

sandblasting in confined spaces, tunneling through rock with a high quartz content (15–25%), or the manufacture of abrasive soaps may develop acute silicosis with as little as 10 months of exposure

chest radiograph may show profuse miliary infiltration or consolidation, and there is a characteristic HRCT pattern known as “crazy paving”

Question 16

long-term, less intense exposure, small rounded opacities in the upper lobes may appear on the chest radiograph after 15–20 years of exposure, usually without associated impairment of lung function

Answer 16

simple silicosis)

Calcification of hilar nodes may occur in as many as 20% of cases and produces a characteristic “eggshell” pattern.

Question 17

The nodular fibrosis may be progressive in the absence of further exposure, with coalescence and formation of nonsegmental conglomerates of irregular masses >1 cm in diameter

Answer 17

complicated silicosis

These masses can become quite large, and when this occurs, the term progressive massive fibrosis (PMF) is applied.

Question 18

COAL WORKER’S PNEUMOCONIOSIS (CWP)
50% of anthracite miners with >20 years of work on the coal face

prevalence of disease is lower in workers in bituminous coal mines

Answer 18

As in silicosis, the presence of these nodules (simple CWP) usually is not associated with pulmonary impairment.

Complicated CWP is manifested by the appearance on the chest radiograph of nodules ≥1 cm in diameter generally confined to the upper half of the lungs

Question 19

Caplan syndrome

Answer 19

first described in coal miners but subsequently in patients with silicosis, is the combination of pneumoconiotic nodules and seropositive rheumatoid arthritis. Silica is often present in anthracitic coal dust and its presence may contribute to risk of PMF.

Question 20

CHRONIC BERYLLIUM DISEASE

Beryllium
lightweight metal with tensile strength, good electrical conductivity, and value in the control of nuclear reactions through ability to quench neutrons

May cause

Answer 20

acute pneumonitis

more commonly associated with a chronic granulomatous inflammatory disease that is similar to sarcoidosis

Question 21

Organic Dust

3

Answer 21

Cotton dust
Grain dust
Farmers dust lung

Question 22

Cotton Dust (Byssinosis)

Answer 22

cotton dust (but also to flax, hemp, or jute dust) in the production o yarns for textiles and rope making are at risk for an asthma-like syndrome known as byssinosis.

The risk of byssinosis is associated with both cotton dust and endotoxin levels in the workplace environment.

Question 23

Byssinosis is characterized

Answer 23

clinically as occasional (early-stage) and then regular (late-stage) chest tightness toward the end of the first day of the workweek (“Monday chest tightness”).

Exposed workers may show a significant drop in FEV1 over the course of a Monday workshift.

After >10 years of exposure, workers with recurrent symptoms are more likely to have an obstructive pattern on pulmonary function testing.

Question 24

Grain Dust

Answer 24

presentation of obstructive airway disease in grain dust–exposed workers is virtually identical to the characteristic findings in cigarette smokers, i.e., persistent cough, mucus hypersecretion, wheeze and dyspnea on exertion, and reduced FEV1 and FEV1/FVC (forced vital capacity) ratio

Dust concentrations in grain elevators >10,000 μg/m3

obstructive ventilatory

byssinosis, endotoxin may play a role in grain dust–induced chronic bronchitis and COPD

Question 25

Farmer’s Lung

Answer 25

exposure to moldy hay containing spores of thermophilic actinomycetes that produce a hypersensitivity pneumonitis (Chap. 282). A patient with acute farmer’s lung presents 4–8 h after exposure with fever, chills, malaise, cough, and dyspnea without wheezing

Patchy fibrosis

Question 26

TOXIC CHEMICALS

Answer 26

283

Question 27

Fluoropolymers such as Teflon

Answer 27

become volatilized upon heating. The inhaled agents cause a characteristic syndrome of fever, chills, malaise, and occasion-ally mild wheezing, leading to the diagnosis of polymer fume fever

Question 28

Nylon flock- cause induce lymphocytic bronchiole ‘tis

Workers exposed to diacetyl which provide butter flavour in manufacture of microwave popcorn and other foods develop

Answer 28

Bronchiolitis obliterances

Question 29

Disability i

Answer 29

the decreased ability to work due to the effects of a medical condition.

Question 30

impairment

Answer 30

assess physiologic dysfunction,

individual be unable to do any work (i.e., total disability) before he or she will receive income replacement payments. Many state workers’ compensation systems allow for payments for partial disability.

Question 31

Particulate matter emission from a coal-fired power plant may react in air to produce acid surfaces and aerosols

Answer 31

Sulfur dioxide

Question 32

Oxides of nitrogen and volatile organic

Answer 32

compounds from automobile exhaust react with sunlight to produce ozone