Chapter 19 Flashcards
risk assessment
is the scientific process of estimating how much harm a particular hazard can cause to human health.
risk management
involves deciding whether or how to reduce a particular risk to a certain level and at what cost.
risk
is the possibility of suffering harm from a hazard that can cause injury, disease, death, economic loss, or environmental damage.
probability
a mathematical statement about how likely one is to suffer harm from a hazard.
toxicity
measures how harmful a substance is in causing injury, illness, or death to a living organism.
dose
the amount of a substance a person has ingested, inhaled, or absorbed through their skin.
bioaccumulation
in which some molecules are absorbed and stored in specific organs or tissues at higher than normal levels.
biomagnification
in which levels of some levels of some potential toxins in the environment are magnified as they pass through food chains and webs.
response
the type and amount of health damage resulting from exposure to a chemical or other agent.
poison/toxin
is a chemical that adversely affects the health of a living human or animal by causing injury, illness, or death.
median lethal dose or LD50
the amount received in one dose that kills 50% of the animals (usually rats and mice) in a test population within a 14-day period.
dose response curve
shows the effects of various dosages of a toxic agent on a group of test organisms.
nonthreshold dose-response model
any dosage of a toxic chemical or ionizing radiation causes harm that increase with the dosage.
threshold dose-response model
a threshold dosage must be reached before any detectable harmful effects, occur presumably low dosages of some substances.
toxic chemical
is a chemical, through its chemical action on life processes, can cause temporary or permanent harm or death to humans or animals.
hazardous chemical
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.
mutagens
chemicals or ionizing radiation that cause or increase the frequency of random mutations, or changes, in the DNA molecules found in cells.
teratogens
chemicals that can cause harm or birth defects to a fetus or embryo.
carcinogens
chemicals or ionizing radiation that can cause or promote cancer.
cancer
the growth of a malignant (cancerous) tumor, in which certain cells multiply uncontrollably.
metastasis
when malignant cells break off from tumors and travel in body fluids to other parts of the body.
hormone mimics
are chemicals similar to estrogens (female sex hormones) they can disrupt the endocrine system by attaching to estrogen receptor molecules
hormone blockers
disrupt the endocrine system by preventing natural hormones such as androgens (male sex hormones) from attaching to their receptors.
precautionary principle
when there is plausible but incomplete scientific evidence (frontier science evidence) of significant harm to humans or the environmental from a proposed or existing chemical or technology, we should take action to prevent or reduce the risk instead of waiting for more conclusive (sound or consensus science) evidence.
nontransmissable disease
is caused by something other than a living organism and does not spread from one person to another.
transmissible disease
is caused by a living organism and can spread from one person to another.
dengue fever
painful and sometimes fatal
carried by four related viruses and strikes during rainy season
2.5 million people at risk; 50 million new cases a year.
malaria
is caused by a parasite that is spread by the bites of certain mosquito species.
yellow fever
dreaded far more than 400 years.
viral disease that causes symptoms from mild to severe illness and death
200000 new cases and 30000 deaths a year.
HIV
(human immunodeficiency virus) that is transmitted by unsafe sex, sharing needles by drug users, infected mothers to offspring before birth, and exposure to infected blood.
influenza
is transmitted by the body fluids or airborne emissions of an infected person and kills about 1 million people a year.
hepatitis B virus
damages the liver and kills about 1 million people a year. transmitted by unsafe sex, sharing of needles by drug users, infected mothers to offspring before or during birth, and exposure to infected blood.
risk analysis
involves identifying hazards and evaluating their associated risks (risk assessment), ranking risks (comparative risk analysis), determining options and making decisions about reducing or eliminating risks (risk management) and informing decision makers and the public about risks (risk communication)
