Chapter 19

Question 1

Risk

Answer 1

the possibility of suffering harm from a hazard that can cause injury, disease, death, economic loss, or environmental damage

Question 2

Risk assessment

Answer 2

the scientific process of estimating how much harm a particular hazard can cause to human health

Question 3

risk management

Answer 3

involves deciding whether or how to reduce a particular risk to a certain level and at what cost

Question 4

probability

Answer 4

a mathematical statement about how likely one is to suffer from a hazard

-Scientists often state probability in terms such as “the lifetime probability of developing lung cancer from smoking a pack of cigarettes a day is 1 in 250”

Question 5

toxicity

Answer 5

measures how harmful a substance is in causing injury, illness, or death to a living organism

Question 6

dose

Answer 6

• a factor that depends the toxicity

- the amount of a substance a person has ingested, inhaled, or absorbed through skin

Question 7

bioaccumulation

Answer 7

• a factor that depends the toxicity

- some molecules are absorbed and stored in specific organs or tissues at higher than normal levels

Question 8

biomagnification

Answer 8

levels of some potential toxins in the environment are magnified as they pass through food chains and webs

Question 9

response

Answer 9

the type and amount of health damage resulting from exposure to a chemical or other agent

Question 10

poison/toxin

Answer 10

a chemical that adversely affects the health of a living human or animal by causing injury, illness, or death

Question 11

median lethal dose (LD50)

Answer 11

the amount received in one dose that kills 50% of the animals in a test population within a 14-day period

Question 12

dose response curve

Answer 12

shows the effects of various dosages of a touched agent on a group of test organisms

Question 13

non threshold dose-response model

Answer 13

proves that any dosage of a toxic chemical or ionizing radiation causes harm that increases with the dosage

Question 14

threshold dose-response model

Answer 14

proves that a threshold dosage must be reached before any detectable harmful effects occur, presumably because the body can repair the damage caused by low dosages of some substances

Question 15

toxic chemical

Answer 15

a chemical, which through its chemical action on life processes, can cause temporary or permanent harm or death to humans or animals
-its toxicity is often measured in terms of its medium lethal dose

Question 16

hazardous chemical

Answer 16

can harm humans or other animals because it is flammable or explosive or because it can irritate or damage the skin or lungs, interfere with oxygen uptake, or induce allergic reactions

Question 17

mutagens

Answer 17

chemicals or ionizing radiation that cause or increase the frequency of random mutations, or changes, in the DNA molecules found in cells

Question 18

teratogens

Answer 18

chemicals that cause harm or birth defects to a fetus or embryo

Question 19

carcinogens

Answer 19

chemicals or ionizing radiation that cause or promote cancer

Question 20

cancer

Answer 20

the growth of a malignant (cancerous) tumor, in which certain cells multiply uncontrollably

Question 21

metastasis

Answer 21

when malignant cells break off from tumors and travel in body fluids to other parts of the body

Question 22

hormone mimics

Answer 22

chemicals similar to estrogens

- they can disrupt the endocrine systems by attaching to estrogen receptors molecules

Question 23

hormone blockers

Answer 23

disrupt the endocrine system by preventing natural hormones such as androgens (male sex hormones) from attaching to their receptors

Question 24

precautionary principle

Answer 24

When there is a plausible but incomplete scientific evidence of a significant harm to humans or the environment from a proposed or existing chemical or technology, we should take action to prevent or reduce the risk instead of waiting for more conclusive evidence

Question 25

non transmissible disease

Answer 25

caused by something other than a living organism and does not spread from one person to another

Question 26

transmissible disease

Answer 26

caused by a living organism and can spread from one person to another

Question 27

dengue fever

Answer 27

• mosquito borne
• related to west nile and yellow fever
• AEdes mosquito
• cannot be spread from person to person

Question 28

malaria

Answer 28

transmitted by the bites of certain mosquito species.. most cases of the disease are transmitted when an uninfected mosquito female from an one of about 60 Anopheles mosquitos species bites an infected person, ingests blood that contains the parasite, and later bites an uninfected person

Question 29

yellow fever

Answer 29

• viral infection transmitted by a bite from infected mosquitos
• damages the liver and other internal organs and be potentially fatal
• cannot be spread humans to humans

Question 30

HIV

Answer 30

• Human immunodeficiency virus
• transmitted by unsafe sex, sharing of needles by drug users, mother to child during birth, episode to infected blood
• infects at least 5 mil. a year

Question 31

influenza

Answer 31

• flu
• second biggest killer that is transmitted by the body fluids or airborne emissions of an infected person and kills about 1 million people per year

Question 32

hepatitis B

Answer 32

• third largest kiler that damages the liver and kills about 1 mil. a year
• transmited by unsafe sex, sharing of needles by drug users, infected mother to child during birth, exposure to infected blood

Question 33

risk analysis

Answer 33

• identifying hazards and evaluating their associated risks
• ranking risks
• determining options and making decisions about reducing or eliminating risks
• informing decision makers and public about risk