PHAR 100- Module 6 UPDATED ACTUAL
Questions and CORRECT Answers
Environmental Toxicants - CORRECT ANSWER - - chemical released into the
environment that can produce adverse health effects on living organisms
Acute toxicity - CORRECT ANSWER - - refers to a single exposure to a chemical, and
often (but not necessarily) a large dose of the chemical; e.g. a chemical spill
- e.g. acute toxicity of Aflatoxin B (common food contaminant in southeast asia and central
africa) can result in liver necrosis, liver failure, or death
Chronic toxicity - CORRECT ANSWER - - generally repeated exposure to small doses of
a chemical over a large period of time; e.g. contaminated food
- e.g. chronic toxicity of Aflatoxin B can cause liver cancer
Air pollution - CORRECT ANSWER - - first air pollution law was established in 1273 by
Edward I, King of England (was illegal to burn coal while parliament was in session)
- first automobiles were manufactured in the 1900s
- "killer smog" in London caused approximately 4000 deaths in 1952; this lead to the clean air
act
- clean air act was introduced in 1956 to reduce pollution (included shifting home heat sources to
cleaner coals, electricity and gas, rather than fireplace smoke)
Categories of major air pollutants - CORRECT ANSWER - - gaseous
- particulate matter
Gaseous air pollutants - CORRECT ANSWER - - carbon monoxide and carbon dioxide
- nitrogen oxides and sulfur oxides
- hydrogen sulfide
- ozone
,Particulate matter - CORRECT ANSWER - - mixture of tiny particles composed of non-
gaseous pollutants (e.g. biological materials)
- can be solid or liquid droplets
natural sources of air pollution - CORRECT ANSWER - - volcanoes
- forest and prairie fires
- dust storms
anthropogenic air pollution - CORRECT ANSWER - - man-made
1) heating and power:
- combustion of fossil fuels releases CO2, CO, sulfur oxides and nitrogen oxides
- coal is the largest contributor to human increases in carbon dioxide
2) automobile exhaust:
- smoke, lead particles, CO and nitrogen oxides
- in the late 20th century, government regulations were put into place for the use of low-lead or
unleaded gas
3) industrial processes:
- wide variety of pollutants; depends on manufacturing process
- includes sulfuric acid, acetic acid, solvents (ethanol), chlorine gas, ammonia gas, and metals
human health and air pollutants - CORRECT ANSWER - - chemical irritation of the
respiratory tract
- more susceptible: children, elderly, and people with cardiorespiratory diseases such as asthma
- health problems are usually due to the combined actions of particulates and sulfur oxides
tobacco smoke - CORRECT ANSWER - - environmental or second-hand smoke is the
combination of mainstream smoke (exhaled) and side stream smoke (from the end of a burning
cigarette)
, - stated in 2002 that exposure causes lung cancer and the same health risks as directly smoking
- numerous bylaws about smoking in public
pesticides - CORRECT ANSWER - - used to intentionally kill organisms
1) insecticides
2) herbicides
insecticides - CORRECT ANSWER - - kill insects or make insects unable to reproduce or
develop normally
1) organochlorine insecticides
2) organophsorphorous insecticides
organochlorine insecticides - CORRECT ANSWER - - work by increasing the sensitivity
of neurons, resulting in increased CNS stimulation, which manifests as tremors and convulsions
- e.g. DDT (dichlorodiphenyltrichloroethane)
DDT (dichlorodiphenyltrichloroethane) - CORRECT ANSWER - - introduced in 1945 to
control malaria-containing mosquitos
- use stopped in the 1970s because:
- insects were developing resistance
- there was a decrease in bird and fish populations
- soil and water concentrations of DDT increased
- levels of DDT in food increased
Toxicity of organochlorine insecticides - CORRECT ANSWER - - residues in humans,
animals and the environment presents long-term problems
- animal studies have found numerous developmental and reproductive effects, as well as an
increase in liver tumours as a result of chronic DDT exposure
- have been largely phased out
Questions and CORRECT Answers
Environmental Toxicants - CORRECT ANSWER - - chemical released into the
environment that can produce adverse health effects on living organisms
Acute toxicity - CORRECT ANSWER - - refers to a single exposure to a chemical, and
often (but not necessarily) a large dose of the chemical; e.g. a chemical spill
- e.g. acute toxicity of Aflatoxin B (common food contaminant in southeast asia and central
africa) can result in liver necrosis, liver failure, or death
Chronic toxicity - CORRECT ANSWER - - generally repeated exposure to small doses of
a chemical over a large period of time; e.g. contaminated food
- e.g. chronic toxicity of Aflatoxin B can cause liver cancer
Air pollution - CORRECT ANSWER - - first air pollution law was established in 1273 by
Edward I, King of England (was illegal to burn coal while parliament was in session)
- first automobiles were manufactured in the 1900s
- "killer smog" in London caused approximately 4000 deaths in 1952; this lead to the clean air
act
- clean air act was introduced in 1956 to reduce pollution (included shifting home heat sources to
cleaner coals, electricity and gas, rather than fireplace smoke)
Categories of major air pollutants - CORRECT ANSWER - - gaseous
- particulate matter
Gaseous air pollutants - CORRECT ANSWER - - carbon monoxide and carbon dioxide
- nitrogen oxides and sulfur oxides
- hydrogen sulfide
- ozone
,Particulate matter - CORRECT ANSWER - - mixture of tiny particles composed of non-
gaseous pollutants (e.g. biological materials)
- can be solid or liquid droplets
natural sources of air pollution - CORRECT ANSWER - - volcanoes
- forest and prairie fires
- dust storms
anthropogenic air pollution - CORRECT ANSWER - - man-made
1) heating and power:
- combustion of fossil fuels releases CO2, CO, sulfur oxides and nitrogen oxides
- coal is the largest contributor to human increases in carbon dioxide
2) automobile exhaust:
- smoke, lead particles, CO and nitrogen oxides
- in the late 20th century, government regulations were put into place for the use of low-lead or
unleaded gas
3) industrial processes:
- wide variety of pollutants; depends on manufacturing process
- includes sulfuric acid, acetic acid, solvents (ethanol), chlorine gas, ammonia gas, and metals
human health and air pollutants - CORRECT ANSWER - - chemical irritation of the
respiratory tract
- more susceptible: children, elderly, and people with cardiorespiratory diseases such as asthma
- health problems are usually due to the combined actions of particulates and sulfur oxides
tobacco smoke - CORRECT ANSWER - - environmental or second-hand smoke is the
combination of mainstream smoke (exhaled) and side stream smoke (from the end of a burning
cigarette)
, - stated in 2002 that exposure causes lung cancer and the same health risks as directly smoking
- numerous bylaws about smoking in public
pesticides - CORRECT ANSWER - - used to intentionally kill organisms
1) insecticides
2) herbicides
insecticides - CORRECT ANSWER - - kill insects or make insects unable to reproduce or
develop normally
1) organochlorine insecticides
2) organophsorphorous insecticides
organochlorine insecticides - CORRECT ANSWER - - work by increasing the sensitivity
of neurons, resulting in increased CNS stimulation, which manifests as tremors and convulsions
- e.g. DDT (dichlorodiphenyltrichloroethane)
DDT (dichlorodiphenyltrichloroethane) - CORRECT ANSWER - - introduced in 1945 to
control malaria-containing mosquitos
- use stopped in the 1970s because:
- insects were developing resistance
- there was a decrease in bird and fish populations
- soil and water concentrations of DDT increased
- levels of DDT in food increased
Toxicity of organochlorine insecticides - CORRECT ANSWER - - residues in humans,
animals and the environment presents long-term problems
- animal studies have found numerous developmental and reproductive effects, as well as an
increase in liver tumours as a result of chronic DDT exposure
- have been largely phased out
