Deck 19: Risk,toxicology,and Human Health

Question 1

What dose-response curve would be implied in an epidemiological study that shows a standard increase in physical effects for each rise in the dose of a toxic substance? 

A) a linear dose-response curve 
B) an exponential dose-response curve 
C) a threshold dose-response curve 
D) no dose-response curve

Answer 1

A

Question 2

Which suggestion is most likely to lead to an increase in the health risks associated with smoking? 

A) eliminate federal subsidies to tobacco farmers and companies 
B) ban cigarette advertising 
C) legalize the sale of tobacco products to all age groups 
D) ban cigarette vending machines

Answer 2

C

Question 3

Which pricing approach is being used if a further tax is added to the price of a pack of cigarettes? 

A) externalizing internal costs approach 
B) full-cost pricing approach 
C) user-pays approach 
D) life-cycle cost pricing approach

Answer 3

C

Question 4

Which type of effect would be displayed by a person experiencing liver damage after a lifetime of alcohol abuse? 

A) a chronic effect 
B) a subchronic effect 
C) a subacute effect 
D) an acute effect

Question 5

What is the best reason for animal use in developing dose-response curves? 

A) It is non-controversial. 
B) Researchers can extrapolate data from test animals to humans. 
C) Researchers can extrapolate data from low-dose levels to high-dose levels. 
D) It is usually nonlethal.

Question 6

Which hazard is considered to be one of the four main types of hazards? 

A) industrial hazards 
B) climate change hazards 
C) chemical hazards 
D) global hazards

Question 7

Who regulates research involving animals in Canada? 

A) the NRA 
B) the SPCA 
C) the DNR 
D) the CCAC

Question 8

How many deaths in Canada are attributed to tobacco? 

A) one in every ten deaths 
B) one in every seven deaths 
C) one in every five deaths 
D) two in every seven deaths

Question 9

Which statement best describes chemicals? 

A) All chemicals are unsafe. 
B) Natural chemicals are safe, and synthetic chemicals are deadly. 
C) Some chemicals, whether synthetic or natural, are safe, and others are deadly. 
D) Both synthetic and natural chemicals are safe.

Question 10

Which of the following is considered a physical hazard? 

A) driving 
B) chemicals 
C) poor diet 
D) a hurricane

Question 11

Which type of effect is occurring if a person is experiencing dizziness after using a strong household cleaner? 

A) an acute effect 
B) a subchronic effect 
C) a subacute effect 
D) a chronic effect

Question 12

How toxic is a substance with an LD50 of 1 milligram/kilogram of body weight? 

A) essentially nontoxic 
B) moderately toxic 
C) toxic 
D) extremely toxic

Question 13

What is used to generate dose-response curves? 

A) epidemiological studies comparing animal responses to various doses 
B) laboratory studies comparing experimental and control groups of test animals 
C) field studies with groups of test subjects 
D) computer models comparing different groups of people

Question 14

Which of the following is considered a biological hazard? 

A) an earthquake 
B) bacteria 
C) a hurricane 
D) diet

Question 15

What would people most likely have experienced if they flew over the Chernobyl site two days after the explosion? 

A) an acute exposure to radioactive substances 
B) a subchronic exposure to radioactive substances 
C) a subacute exposure to radioactive substances 
D) a chronic exposure to radioactive substances

Question 16

What type of exposure would have been experienced by a person who received a lifetime of background radiation from a low-level radioactive dump site? 

A) a subacute exposure to radioactive substances 
B) a chronic exposure to radioactive substances 
C) a subchronic exposure to radioactive substances 
D) an acute exposure to radioactive substances

Question 17

Which type of effect would be displayed by a person with kidney damage after an immediate exposure to a toxic chemical? 

A) a subacute effect 
B) a subchronic effect 
C) a chronic effect 
D) an acute effect

Question 18

Which of the following statements is true about determining exposure levels of toxins? 

A) Since there is considerable uncertainty involved, exposure levels are set at 1/100 or even 1/1000 of the level expected to cause harm. 
B) Since toxic exposure levels can be determined with great accuracy, limits tend to be set just under the harmful level to accommodate the chemical and pharmaceutical industries. 
C) Since the actions of toxins, and combinations of various toxins, are well understood, there is no need for continued toxicity studies involving humans or other animals. 
D) Citizens can rest assured that there will be no surprises arising from the toxic effects of chemicals, or combinations of chemicals, because of the extreme certainties arising from the toxicity studies done to date.

Question 19

Which of the following is considered a cultural hazard? 

A) floods 
B) drugs 
C) drought 
D) pollen

Question 20

Which statement best describes dose-response curves? 

A) They are extrapolated from humans to other primates. 
B) They show the effects of various doses of toxic agents on a group of test organisms. 
C) They are extrapolated using mathematical models to project possible effects of high doses. 
D) They are linear graphs.

Question 21

How many years of delay is typical between initial exposure to a carcinogen and appearance of detectable symptoms? 

A) 2 to 5 years 
B) 5 to 10 years 
C) 10 to 40 years 
D) 40 to 50 years

Question 22

What is a characteristic of mutagens? 

A) They cause mutations. 
B) They are harmful because they are flammable, explosive, irritating to skin or lungs, or cause allergic reactions. 
C) They are fatal to humans in low doses. 
D) They cause physical deformities.

Question 23

What medical problem is caused by carcinogens? 

A) birth defects 
B) chronic health effects 
C) cancer 
D) genetic defects

Question 24

What legislation regulates the 23,000 chemical substances that are available for commercial use in Canada? 

A) the Chemical Protection Act (CPA) of each individual province and territory 
B) the Toxic Chemicals Act (TCA) 
C) the Canadian Environmental Protection Act (CEPA) 
D) the Canadian Commercial Chemical Control Act (CCCCA)

Question 25

Which of the following is a line of defense in the human body's immune system? 

A) hormones 
B) antibodies 
C) neurotoxins 
D) neurohumors

Question 26

Which class of chemicals causes birth defects? 

A) iodized sodium chloride 
B) teratogens 
C) carcinogens 
D) glycogens

Question 27

Which type of molecule is directly changed by mutagens? 

A) carbohydrate 
B) RNA 
C) protein 
D) DNA

Question 28

Which of the following is a type of chemical hazard? 

A) a hormone 
B) LC50 
C) a zymogen 
D) a mutagen

Question 29

What is a characteristic of teratogens? 

A) They are harmful because they are irritating to skin or lungs. 
B) They cause birth defects. 
C) They cause mutations. 
D) They are fatal to humans in low doses.

Question 30

Which statement best describes a threshold dose-response model? 

A) It implies there is a dose below which no detectable harmful effects occur. 
B) It implies that each dose of ionizing radiation or toxic chemical carries a risk of causing harm. 
C) It is useful for assessing chronic toxicity. 
D) It errs on the side of safety.

Question 31

Which system can be severely disrupted when a person intakes synthetic mimics? 

A) the circulatory system 
B) the digestive system 
C) the endocrine system 
D) the respiratory system

Question 32

Who would be most affected by bioaccumulation of a hormone disrupter? 

A) a tertiary consumer 
B) a producer 
C) a primary consumer 
D) a secondary consumer

Question 33

Which of the following is a transmissible disease? 

A) malnutrition 
B) hepatitis B 
C) cancer 
D) heart disease

Question 34

What is the best definition of a vector? 

A) an agent of disease transmission 
B) a parasitic organism 
C) a dosage level 
D) an agent of infection

Question 35

Which synthetic substance acts as an endocrine disruptor? 

A) high-fructose corn syrup 
B) caffeine 
C) Bisphenol-A 
D) ethyl alcohol

Question 36

Which system is responsible for the human body's defense against disease and harmful substances? 

A) the immune system 
B) the circulatory system 
C) the excretory system 
D) the endocrine system

Question 37

What is least likely to cause a transmissible disease? 

A) a hazardous chemical 
B) a virus 
C) bacteria 
D) a parasite

Question 38

What is metastasis? 

A) the process of dying from cancer 
B) the result of coming into contact with a carcinogen 
C) the surgical removal of a tumour 
D) when malignant cells break off from tumours to other parts of the body

Question 39

What plays the most important role in causing or promoting cancer,according to the World Health Organization? 

A) cigarette smoke 
B) genetic factors 
C) viruses 
D) environmental pollutants

Question 40

Which population of a large lake system would be most affected by the dumping of PCBs into the water? 

A) algae 
B) zooplankton 
C) small fish 
D) predatory birds

Question 41

What is the greatest contributor to reducing a person's life span? 

A) smoking 
B) high cholesterol 
C) poverty 
D) cancer

Question 42

Which organism spreads malaria? 

A) flies 
B) worms 
C) mosquitoes 
D) snails

Question 43

Which of the following is a viral disease? 

A) tuberculosis 
B) Lyme disease 
C) influenza 
D) malaria

Question 44

What causes tuberculosis? 

A) mosquitoes 
B) viruses 
C) houseflies 
D) bacteria

Question 45

What is a leading cause of death in developed countries? 

A) bacteria 
B) environmental and lifestyle factors 
C) vectors 
D) viruses

Question 46

What is a key characteristic of bacteria? 

A) They have a low reproductive rate. 
B) They cannot adapt to changing environments. 
C) They can develop resistance to antibiotics. 
D) They are K-strategists.

Question 47

What causes malaria? 

A) viruses 
B) plasmodium parasites 
C) bacteria 
D) parasitic worms

Question 48

Which strategy has the most potential to help curtail the increasing resistance of bacterial strains to antibiotics? 

A) if humans wear protective masks 
B) if humans continue using antibiotics 
C) if humans decrease their use of pesticides 
D) if humans use improved sanitation procedures, especially hand washing

Question 49

Which malaria reduction strategy would be most harmful to humans? 

A) spraying heavier doses of DDT on swamps and estuaries 
B) using mosquito nets dipped in permethrin 
C) increasing water flow in irrigation systems 
D) cultivating fish that feed on mosquito larvae

Question 50

Which of the following is part of the process of risk assessment? 

A) determining the types of hazards involved 
B) informing decision makers and the public about risks 
C) determining how much money should be spent 
D) communicating risk to the general public

Question 51

What presents the greatest health risk to a person living in a developing country? 

A) unsanitary drinking water 
B) diabetes 
C) hantavirus 
D) Ebola virus

Question 52

Which of the following is a physical hazard? 

A) poverty 
B) a flood 
C) poor diet 
D) allergens

Question 53

Which statement best describes an epidemiologic transition? 

A) It happens before a demographic transition. 
B) It happens when mortality is due mainly to childhood infectious diseases rather than adulthood chronic diseases. 
C) It happens when mortality is due mainly to adulthood chronic diseases rather than childhood infectious diseases. 
D) It is the same as a demographic transition.

Question 54

Which one of the following has been a low-cost investment that has saved millions of lives from diarrheal diseases annually? 

A) postnatal care 
B) immunization against preventable infectious diseases 
C) family-planning counseling 
D) oral rehydration therapy

Question 55

What percentage of global deaths are caused by infectious and parasitic diseases? 

A) about 8% 
B) about 18% 
C) about 28% 
D) about 38%

Question 56

What is a symptom of malaria? 

A) curvature of the spine 
B) weakened immune system 
C) blindness 
D) elevated red blood cell count

Question 57

What would be most effective for improving healthcare in developing countries? 

A) implementing better cooking technology 
B) implementing better exercise programs 
C) immunizing people against the measles 
D) implementing oral rehydration therapy

Question 58

Which factor contributes most to the rise in the incidence of bacterial diseases that were once controlled by antibiotics? 

A) the genetic adaptability of bacteria 
B) the increased amount of ultraviolet light that is entering the Earth's atmosphere due to the thinning ozone layer 
C) the increased amount of virus around the globe 
D) the underuse of antibiotics by doctors

Question 59

What presents the greatest risk to humans,in terms of the number of deaths per year and reduced life span? 

A) poverty 
B) TB 
C) unhealthy life choices 
D) cultural hazards

Question 60

What led to a sharp decrease in the spread of malaria? 

A) the use of herbicides 
B) the spraying of breeding areas with DDT and other pesticides 
C) the creation of a vaccine 
D) administering a solution of boiled water, salt, and sugar or rice

Question 61

A transmissible disease is caused by something other than a living organism and can spread from one person to another.

Question 62

Under the precautionary principle approach,chemicals are assumed to be safe until scientific research can determine otherwise.

Question 63

All chemicals intended for commercial use are screened for toxicity before being deemed acceptable for use.

Question 64

The three most pervasive viral diseases are influenza,hepatitis B,and SARS.

Question 65

After poverty and gender,the greatest risks faced by people are related mainly to lifestyle choices.

Question 66

Which question can be answered by risk management? 

A) How much will sea levels rise by 2100? 
B) How can risk be eliminated entirely? 
C) How much is a life worth? 
D) When will peak oil be reached?

Question 67

Evaluating the relative health risks for an individual involves looking at the environmental conditions,food resources,and the military security of that individual's population.

Question 68

What is one reason why risk assessment and risk-benefit analyses are useful? 

A) They focus on areas of investment that can make money. 
B) They help regulators decide how money for reducing risks should be allocated. 
C) They increase technological reliability. 
D) They eliminate uncertainties about planning the future.

Question 69

How does human reliability compare to technological reliability? 

A) Human reliability is much greater than technological reliability. 
B) Human reliability is slightly greater than technological reliability. 
C) Human reliability is slightly lower than technological reliability. 
D) Human reliability is much lower than technological reliability.

Question 70

Although the threat of infectious diseases has decreased,human health is still threatened by pesticide-resistant insects and antibiotic-resistant bacteria.

Question 71

Most case reports provide reliable sources for estimating the toxicity of harmful chemicals to humans.

Question 72

Which statement best describes why regulators who set human exposure levels for toxic substances usually divide the results to ensure a margin of safety? 

A) because of technological unreliability 
B) because the results of risk analysis are uncertain 
C) because of strict government regulations 
D) because the majority of individuals are unable to evaluate the relative risks they face

Question 73

Research has indicated that long-term exposure to some chemicals at low doses may disrupt the immune,nervous,and endocrine systems of humans.

Question 74

Chemical hazards are defined by their pervasiveness in the environment; the toxicity of the chemicals is not important.

Question 75

The three types of toxic chemicals are mutagens,teratogens,and carcinogens.

Question 76

Cigarette smoking is an example of a preventable hazard.

Question 77

A nonlinear dose response model applies if a harmful effect occurs when the dosage exceeds a threshold level.

Question 78

What is required to calculate the risk of a new technological system? 

A) a careful economic analysis 
B) an assessment of its reliability 
C) the system's energy efficiency 
D) an assessment of human intelligence

Question 79

Malaria cannot be transmitted by blood transfusions or by sharing needles.

Question 80

Case reports,epidemiological studies,and animal testing can all be used to estimate toxicity.