APES Chapter 18

cancer

Group of more than 120 different diseases, one for each type of cell in the human body. Each type of cancer produces a tumor in which cells multiply uncontrollably and invade surrounding tissue.

carcinogen

Chemicals, ionizing radiation, and viruses that cause or promote the development of cancer.

dose

The amount of a potentially harmful substance an individual ingests, inhales, or absorbs through the skin.

dose-response curve

Plot of data showing effects of various doses of a toxic agent on a group of test organisms.

epidemiology

Study of the patterns of disease or other harmful effects from toxic exposure within defined groups of people to find out why some people get sick and some do not.

hazard

Something that can cause injury, disease, economic loss, or environmental damage.

hazardous chemical

Chemical that can cause harm because it is flammable or explosive, can irritate or damage the skin or lungs (such as strong acidic or alkaline substances), or can cause allergic reactions of the immune system (allergens).

infectious disease

See transmissible disease.

LD50 (median lethal dose)

Amount of a toxic material per unit of body weight of test animals that kills half the test population in a certain time.

metastasis

Spread of malignant (cancerous) cells from a tumor to other parts of the body.

mutagen

Chemical or form of radiation that causes inheritable changes (mutations) in the DNA molecules in the genes found in chromosomes.

neurotoxins

Chemicals that can harm the human nervous system (brain, spinal cord, peripheral nerves).

nontransmissible disease

A disease that is not caused by living organisms and does not spread from one person to another. Examples are most cancers, diabetes, cardiovascular disease, and malnutrition.

pathogen

Organism that produces disease.

poison/toxin

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

probability

A mathematical statement about how likely it is that something will happen.

response

The amount of health damage caused by exposure to a certain dose of a harmful substance or form of radiation.

risk

The probability that something undesirable will result from deliberate or accidental exposure to a hazard.

risk analysis

Identifying hazards, evaluating the nature and severity of risks (risk assessment), using this and other information to determine options and make decisions about reducing or eliminating risks (risk management), and communicating information about risks to decision makers and the public (risk communication).

risk assessment

Process of gathering data and making assumptions to estimate short- and long-term harmful effects on human health or the environment from exposure to hazards associated with the use of a particular product or technology.

risk communication

Communicating information about risks to decision makers and the public.

risk management

Using risk assessment and other information to determine options and make decisions about reducing or eliminating risks.

teratogen

Chemical, ionizing agent, or virus that causes birth defects.

toxic chemical

See poison, carcinogen, hazardous chemical, mutagen, teratogen.

toxicity

Measure of how harmful a substance is.

toxicology

Study of the adverse effects of chemicals on health.

transmissible disease

A disease that is caused by living organisms (such as bacteria, viruses, and parasitic worms) and can spread from one person to another by air, water, food, or body fluids (or in some cases by insects or other organisms).

synergistic

Combined effect is greater than the sum of their individual effects. Explains why mixing alcohol and sedatives is so dangerous; or smoking tobacco and being exposed to asbestos.