Toxic Gases Flashcards
What is the source of nitrogen dioxide?
Fermentation of corn/forages high in nitrate
When do you get the highest concentration of nitrogen dioxide?
Within the first 48 hours of ensiling
Is nitrogen dioxide heavier or lighter than air?
Heavier
True or False: Nitrogen dioxide causes oxidative stress.
True
Nitrogen dioxide causes ____ and ____ irritation.
Ocular and upper airway irritation
Nitrogen dioxide causes which of the following: chronic bronchitis, fever, emphysema, corneal damage.
- Chronic bronchitis
- Fever
- Emphysema
What type of lung lesions might be associated with a nitrogen dioxide toxicity?
- Edema
- Hemorrhage
- Emphysema
- Bronchiolar inflammation
What is methane’s MOA?
Asphyxiation (displacement of oxygen)
Is methane lighter or heavier than air?
Lighter
Which of the following has a pungent odor, methane or nitrogen dioxide?
Nitrogen dioxide (methane is odorless)
Methane is explosive at ___% in the atmosphere.
5%
Methane is what % of natural gas?
85%
Which of the following is odorless, ammonia or CO2?
CO2
Is CO2 heavier or lighter than air?
Heavier
At what percentage does CO2 induce a coma?
25%
Is ammonia heavier or lighter than air?
Lighter
What are 3 sources of ammonia?
- Fertilizers
- Manure
- Chicken houses
At what ppm is ammonia a chronic stressor?
> 50 ppm
Ammonia causes ____ and ____ irritation.
Eye and respiratory
Ammonia causes corneal damage at ____ ppm.
100 ppm
NH3 causes corneal injury in poultry at ___ ppm.
60-75 ppm
NH3 causes increased respiratory disease at ____ ppm.
50 ppm
NH3 causes decreased egg production at ____ ppm.
20 ppm
Is hydrogen sulfide heavier or lighter than air?
Heavier (collects in low places)
At what ppm does H2S cause olfactory paralysis?
200 ppm
At what ppm does H2S causes pulmonary edema?
> 500 ppm
At what ppm does H2S cause respiratory paralysis?
> 1000 ppm
At what ppm does H2S quickly cause death after a few violent gasps?
> 3000 ppm
H2S is a direct irritant of ____ and ____.
Eyes and lungs
What type of general metabolic effect does H2S have?
Inhibition of cytochrome oxidase
What type of lesions would you associated with HS2?
- Pulmonary edema
- Dark blood
- Tissues that smell of H2S
What 4 drugs are experimentally possible H2S antidotes?
- Nitrites
- Thiamine
- Cobinamide
- Hydroxycobolamine
Is carbon monoxide heavier or lighter than air?
Lighter than air
Why is carbon monoxide called the “silent killer”?
- Colorless
2. Odorless
What is the source of toxicity if an automobile engine is left running in a closed garage?
Carbon monoxide
What type of poisoning should be suspected in any animal rescued from a fire?
Carbon monoxide
What is the MOA of carbon monoxide?
CO is absorbed into the lungs –> CO combines with hemoglobin –> formation of COHb –> anoxia
Hemoglobin has an affinity for CO that is ____ times that of its affinity for O2.
300
What causes cherry-red skin and mucous membranes?
Carbon monoxide poisoning
Explain how you could diagnose a carbon monoxide poisoning.
- Measure carboxyhemoglobin levels
- Measure carboxyhemoglogin in fetal serosanguinous thoracic fluid
- Measure CO in the environment
What causes necrosis of superficial layers such as the dermis of the muzzle and the epithelium of the trachea?
Anhydrous ammonia
What are 4 sources of hyperthermia?
- Metabolic activity (large animals)
- Manure pits
- Poor ventilation
- Thermal input
Which species is most susceptible to PTFE (polytetrafuoroethylene)?
Pet birds
How would you prevent PTFE? (list 3 ways)
- Don’t use non-stick cookware
- Remove birds from the house
- Ventilate well
