APES Chapter 17 - Human Health and Environmental Risks

Disease

Any impaired function of the body with a characteristic set of symptoms.

Infectious disease

A disease caused by a pathogen.

Acute disease

A disease that rapidly impairs the functioning of an organism.

Chronic disease

A disease that slowly impairs the functioning of an organism.

Epidemic

A situation in which a pathogen causes a rapid increase in disease.

Pandemic

An epidemic that occurs over a large geographic region.

Plague

An infectious disease caused by a bacterium (Yersinia pestis) that is carried by fleas.

Malaria

An infectious disease caused by one of several species of protists in the genus Plasmodium.

Tuberculosis

A highly contagious disease caused by the bacterium Mycobacterium tuberculosis that primarily infects the lungs.

Emergent infectious disease

An infectious disease that has not been previously described or has not been common for at least 20 years.

Acquired Immune Deficiency Syndrome (AIDS)

An infectious disease caused by the human immunodeficiency virus (HIV).

Human Immunodeficiency Virus (HIV)

A type of virus that causes Acquired Immune Deficiency Syndrome (AIDS).

Ebola hemorrhagic fever

An infectious disease with high death rates, caused by several species of the Ebola virus.

Mad cow disease

A disease in which prions mutate into deadly pathogens and slowly damage a cow’s nervous system.

Prion

A small, beneficial protein that occasionally mutates into a pathogen.

Swine flu

A type of flu caused by the H1N1 virus.

Bird flu

A type of flu caused by the H5N1 virus.

Severe acute respiratory syndrome (SARS)

A type of flu caused by a coronavirus.

West Nile virus

A virus that lives in hundreds of species of birds and is transmitted among birds by mosquitoes.

Lyme disease

A disease caused by a bacterium (Borrelia burgdorferi) that is transmitted by ticks.

Zika virus disease

A disease caused by a pathogen that causes fetuses to be born with unusually small heads and damaged brains.

Neurotoxin

A chemical that disrupts the nervous systems of animals.

Carcinogen

A chemical that causes cancer.

Mutagen

A type of carcinogen that causes damage to the genetic material of a cell.

Teratogen

A chemical that interferes with the normal development of embryos or fetuses.

Allergen

A chemical that causes allergic reactions.

Endocrine disruptor

A chemical that interferes with the normal functioning of hormones in an animal’s body.

Dose-response study

A study that exposes organisms to different amounts of a chemical and then observes a variety of possible responses, including mortality or changes in behavior or reproduction.

Acute study

An experiment that exposes organisms to an environmental hazard for a short duration.

Chronic study

An experiment that exposes organisms to an environmental hazard for a long duration.

LD50

The lethal dose of a chemical that kills 50 percent of the individuals in a dose-response study.

Sublethal effect

The effect of an environmental hazard that is not lethal, but which may impair an organism’s behavior, physiology, or reproduction.

ED50

The effective dose of a chemical that causes 50 percent of the individuals in a dose-response study to display a harmful, but nonlethal, effect.

No-observed-effect level (NOEL)

The highest concentration of a chemical that causes no lethal or sublethal effects.

Retrospective study

A study that monitors people who have been exposed to an environmental hazard such as a harmful chemical at some time in the past.

Prospective study

A study that monitors people who might become exposed to an environmental hazard, such as a harmful chemical in the future.

Synergistic interaction

A situation in which two risks together cause more harm than expected based on the separate effects of each risk alone.

Route of exposure

The way in which an individual might come into contact with an environmental hazard such as a chemical.

Solubility

How well a chemical dissolves in a liquid.

Bioaccumulation

An increased concentration of a chemical within an organism over time.

Biomagnification

The increase in chemical concentration in animal tissues as the chemical moves up the food chain.

Persistence

The length of time a chemical remains in the environment.

Environmental hazard

Anything in the environment that can potentially cause harm.

Innocent-until-proven-guilty principle

A principle based on the belief that a potential hazard should not be considered an actual hazard until the scientific data definitively demonstrate that it actually causes harm.

Precautionary principle

A principle based on the belief that action should be taken against a plausible environmental hazard.

Stockholm Convention

A 2001 agreement among 127 nations concerning 12 chemicals to be banned, phased out, or reduced.

REACH

A 2007 agreement among the nations of the European Union about regulation of chemicals; the acronym stands for registration, evaluation, authorization, and restriction of chemicals.