07c: Environmental Pathology

Question 1

Major constituents of smog (with upper safety limits set by EPA):

Answer 1

1. Ozone
2. CO
3. Sulfur and nitrogen dioxide
4. Particulates

Question 2

Ozone is toxic because:

Answer 2

Highly reactive oxidant (ROS generated, lung epithelium damaged)

Question 3

List examples of indoor air pollutants.

Answer 3

1. Radon
2. Asbestos fibers
3. Formaldehyde (gas)

Question 4

(X) is radioactive gas derived from uranium. It can be found in (Y) or uranium mines and the toxic effects have been tied to (Z) disease.

Answer 4

X = radon
Y = soil (in some basements)
Z = lung cancer

Question 5

(X) pollutant was found in insulation, floor, and ceiling tiles before it was banned in 1970. Its toxic effects have been tied to (Y) diseases.

Answer 5

X = asbestos fibers
Y = Mesothelioma, lung fibrosis and lung cancer

Question 6

(X) pollutant can come from foam insulation, glue, wood products. Its toxic effects have been tied to (Y) diseases.

Answer 6

X = formaldehyde
Y = asthma, ENT irritation, dermatitis

Question 7

(X) heavy metal has toxic hematologic, skeletal, neuro, GI, and renal effects (especially in children). What’s the mechanism of toxicity?

Answer 7

X = lead

Binds sulfhydryl groups in proteins and blocks Ca metabolism

Question 8

(X) heavy metal has toxic effects on CNS (tremors, confusion, retardation, death). What’s the mechanism of toxicity?

Answer 8

X = mercury

Binds sulfhydryl groups in proteins (esp CNS and kidney)

Question 9

Ankle X-ray shows radiodense lines in epiphyses from poor remodeling of cartilage/bone trabeculae. You suspect (X) poisoning.

Answer 9

X = lead

Question 10

(X) heavy metal found in soil, water, herbicides (and used historically as murder weapon). What’s the mechanism of toxicity?

Answer 10

X = arsenic

Replaces ATP phosphates (inhibits mito ox phosphorylation)

Question 11

Hyperpigmentation and hyperkeratosis are common clinical features of (X) heavy metal poisoning.

Answer 11

X = arsenic

Question 12

List examples of toxic volatile organic compounds, which mainly enter body via (X) route.

Answer 12

X = lung

1. Chloroform, carbon tetrachloride
2. Benzene, 1,3-butadiene

Question 13

List examples of toxic organic compounds in manufactured products, which mainly enter body via (X) routes.

Answer 13

X = skin, Gi, resp tracts

1. Organochlorines
2. Vinyl chloride monomer (VCM)
3. Phthalate esters

Question 14

Chloracne is acne-like eruption with (X) features. It results from exposure to:

Answer 14

X = cysts, hyperpigmentation and hyperkeratosis

Organochlorines

Question 15

T/F: Smoking (cigarette, cigar, pipe) causes 1 in 10 deaths per year.

Answer 15

False - 1 in 5

Question 16

Smoking (cigarette, cigar, pipe) accounts for (X)% of lung cancer. Quitting before age 40 reduces risk of dying from smoking-related disease by (Y)%.

Answer 16

X = Y = 90

Question 17

Smoking: inflammation and mucus production (bronchitis) increases (X) cells in lung. This (increases/decreases) elastase activity, resulting in:

Answer 17

X = neutrophils
Increases;
Elastin destruction in alveolar walls (emphysema)

Question 18

EtOH toxicity mechanism: its metabolism causes (increase/decrease) in (X), thus generating toxic (Y).

Answer 18

Decrease;
X = NAD
Y = acetaldehyde (carcinogen)

Question 19

EtOH toxicity effects (incoordination, memory impairment, sleepiness, nausea, etc.) are effects of (X) compound.

Answer 19

X = acetaldehyde

Question 20

EtOH toxicity: what causes the fat (breakdown/accumulation)?

Answer 20

Accumulation;
Low NAD (required for FA ox)

Question 21

Tolerance to alcohol is determined genetically based on levels which enzyme(s)? What roles do they play?

Answer 21

1. ADH (EtOH to acetaldehyde)

2. ALDH (acetaldehyde to acetic acid)

Question 22

T/F: Individuals with low alcohol tolerance are protected against alcoholism.

Answer 22

True

Question 23

Drunk driving in US correlated with (X) concentration of EtOH on breath test.

Answer 23

X = 80 mg/dL blood

Question 24

Acute alcoholism results in (activation/depression) of neuronal centers and can result in which respiratory changes at high EtOH levels?

Answer 24

Depression;

Resp arrest

Question 25

(X) injury type is scraping/rubbing and removal of superficial layer.

Answer 25

X = abrasion

Question 26

(X) injury type is bruise from blunt object; extravasation of blood into tissue.

Answer 26

X = contusion

Question 27

(X) injury type is tear/disruptive stretch from blunt object. Bridging blood vessels are (severed/intact).

Answer 27

X = laceration | Intact

Question 28

Incised wound, unlike (X) injury type, has (severed/intact) bridging blood vessels.

Answer 28

X = laceration | Intact

Question 29

(X) injury type is pierced tissue from penetration of long, narrow, sharp object.

Answer 29

X = puncture wound

Question 30

Thermal burn: which characteristics of burn are taken into account?

Answer 30

1. Depth 2. % body surface 3. Internal injuries (from inhalation of hot/toxic fumes)

Question 31

"Superficial" 1st degree burns involve (X) layer(s). They tend to be red, (moist/dry), and painful.

Answer 31

X = epidermis | Dry

Question 32

"Partial thickness" 2nd degree burns involve (X) layer(s). They tend to be red, (moist/dry), and painful.

Answer 32

X = epidermis and some dermis | Moist (blisters)

Question 33

"Full thickness" 3rd/4th degree burns involve (X) layer(s).

Answer 33

X = epidermis and full dermis

Question 34

T/F: Full thickness burns are anesthetic; and layers incapable of regeneration.

Answer 34

True

Question 35

T/F: 1st degree burns have highest risk of infection.

Answer 35

False - 3rd/4th degree

Question 36

Heat stroke: prolonged core temp of over (X)oC causes peripheral (vasodilation/vasoconstriction) and thus:

Answer 36

X = 40 (104oF) Vasodilation Reduced blood flow to brain/heart (confusion, coma, death)

Question 37

Local hypothermia (frostbite) involves (increase/decrease) in vessel permeability and crystallization of (intra/extra)-cellular water.

Answer 37

Increase; | Both

Question 38

Systemic hypothermia involves (hypo/hyper)-ventilation and becomes "severe" at core temp under (X)oC.

Answer 38

Mild (hyperventilation), moderate (hypoventilation X = 28 (under 82oF)

Question 39

T/F: Electical injury: Wet skin lowers resistance by 100-fold.

Answer 39

True

Question 40

Ionizing radiation is damaging to DNA via (direct/indirect) mechanism.

Answer 40

Direct and indirect (via free radicals)

Question 41

Radiopneumonitis is a severe (X) caused by (Y) exposure.

Answer 41

``` X = fibrosis of lung Y = ionizing radiation ```

Question 42

T/F: Only long-term UV radiation causes depletion of Langerhans cells.

Answer 42

False - short-term also

Question 43

Leathery, wrinkled skin from prolonged UV radiation is a result of:

Answer 43

Elastin and collagen breakdown