APES Chapter 17

threshold dose response model

a certain level of the chemical must be reached before any detectable harmful effects occur, presumably because the body can repair the damage caused by low dosages of some substances

toxic chemical

a chemical that can cause temporary or permanant harm or death to humans and animals.

endocrine system

a complex network of glands that release tiny amounts of hormones into the bloodstreams of humans and other vertebrate animals

nontransmissible disease

a disease caused by something other than a living organism and does not spread from person to person.

emergent disease

a disease that is newly discovered or was absent in human populations for at least 20 years.

pandemic

a global epidemic such as tuberculosis or AIDs

epidemic

a large-scale outbreak of an infectious disease in an area or a country

toxicity

a measure of the harmfulness of a susbstance- its ability to cause injury.

receptors

a unique molecular shape of a hormone that allows it to attach to certain parts of cells and to transmit its chemical message

acute effect

an immediate or rapid harmful reactions ranging from dizziness and nausea to death

transmissible disease

an infectious disease that can be transmitted from one persion to another.

pathogen

an organism that can cause disease in another organism.

non threshold does response model

any dosage of a toxic chemical causes harm that increases with the dosage

hormones

are molecules that act as messengers in the endocrine system to regulate various bodily processes, including reproduction, growth, and development

infectious disease

caused when a pathogen such as a bacterium, virus, or parasite invades the body and multiplies in its cells and tissues.

mutagens

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

teratogens

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

carcinogens

chemicals, types of radiation, or certain viruses that can cause or promote cancer.

risk management

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

natural hazard

hazards from fire, earthquakes, volcanic eruptions, floods, and storms

chemical hazard

hazards from harmful chemicals in air, water, soil, food, and human-made products

biological hazard

hazards from more than 1,400 pathogens that can infect humans like bacteria, viruses, parasites, protozoa, and fungi

lifestyle choices

hazards from smoking making poor food choices, drinking too much alcohol, and having unsafe sex

cultural hazard

hazards from unsafe working conditions, unsafe highways, criminal assault, and poverty

risk analysis

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

chronic effect

is a permanent or long-lasting consequence of exposure to a single does or to repeated lower does of a harmful substance

hormonally active agents (HAA)

molecules of certain pesticides and other synthetic chemicals that allows them to attach to molecules of natural hormones and disrupt the endocrine systems in people and some other animals

neurotoxins

some natural and synthetic chemicals in the environment that can harm the human nervous system

dose

the amount of a harmful chemical that a person has ingested, inhaled, or absorbed through the skin.

response

the damage to health resulting from exposure to a chemical.

median lethal dose (LD50)

the dose that can kill 50% of the animals (usually rats and mice) in a test population within an 18-day period

lethal dose

the dose that will kill animal

dose-response curve

the plotting of the effects of various doses of a chemical on a test animal.

Risk

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

risk assessment

the process of using statistical methods to estimate how much harm a particular hazard can cause to human health or to the environment.

toxicology

the study of the harmful effects of chemicals on humans and other organisms. (the study of poisons)

precautionary principle

when there is substantial preliminary evidence that an activity, technology, or chemical substance can harm humans or the environment, we should take precautionary measures to prevent or reduce such harm, rather than waiting for more conclusive scientific evidence