1. Atrazine is one of the most widely used agricultural pesticides in the U.S. that may be applied before and after planting to control broadleaf and grassy weeds. It is used primarily on corn, sorghum, sugarcane, Christmas trees, and other crops. If the oral LD50 of Atrazine is 2,000 mg/kg, what is the oral lethal dose in ounces of this pesticide for a 190-lb pesticide applicator?

a. 12

b. 8

c. 6

d. 4

2. Which of the following statements is FALSE regarding ammonia?

a. Ammonia is lighter than air and disperses quickly into the atmosphere.

b. Ammonia can ignite in air without an ignition source as long as its concentration is within its flammable range.

c. Ammonia fires are not sustainable unless they are exposed to additional heat source.

d. If the ammonia concentration within an enclosure is within its flammable range, no activities should ever be conducted inside the enclosure.

3. Using a pulse CO-oximeter, a paramedic establishes that the blood of an on-duty fire fighter contains carboxyhemoglobin at a concentration of 55,000 ppm by volume. What would be the symptoms?

a. No symptoms

b. Fainting, increased respiration and pulse, coma with intermittent convulsions

c. Possible death

d. Respiratory failure and death

4. Below is a list of chemicals with their oral LD50 in mg/kg (rats). Select the substance that is MOST toxic to rats.

a. DDT, 87 mg/kg

b. malathion, 885 mg/kg

c. carbaryl (sevin), 307 mg/kg

d. parathion, 3 mg/kg