Unit 8 - Aquatic and Terrestrial Pollution

Point source

A distinct, identifiable location that discharges pollutants, such as a factory pipe.

Nonpoint source

A diffuse area that produces pollution, such as agricultural runoff from entire fields.

Homeostasis

A tendency to maintain a balanced or constant internal state; the regulation of any aspect of body chemistry, such as blood glucose, around a particular level

Polychlorinated biphenyls (PCBs)

Industrial chemicals used in plastics and insulators, persistent in the environment and highly toxic.

Neurotoxins

Chemicals that disrupt the nervous systems of animals, such as lead and mercury.

Carcinogens

Chemicals or substances that cause cancer by causing uncontrolled cell growth.

Mutagen

A chemical or physical agent that causes mutations in DNA.

Teratogen

A substance that interferes with normal prenatal development, causing birth defects.

Allergen

A substance that causes an abnormally high, immune-system response in some organisms.

Endocrine disruptors

Chemicals that interfere with the normal functioning of hormones in an animal's body.

Wastewater

Water produced by human activities, including human sewage and graywater from bathing.

Levee

An enlarged bank built up on each side of a river to prevent flooding.

Dikes

Structures built to prevent ocean waters from flooding adjacent land.

Dam

A barrier that runs across a river or stream to control the flow of water.

Reservoir

The body of water created behind a dam.

Fish ladder

A stair-like structure that allows migrating fish to get around a dam.

Desalination (desalinization)

The process of removing salt from salt water to obtain fresh water.

Distillation

Desalination process where water is boiled and the steam is condensed to yield pure water.

Reverse osmosis

Desalination process forcing water through a semipermeable membrane, leaving salt behind.

Eutrophication

An abundance of nutrients in a body of water, leading to algal blooms.

Oxygen sag curve

The curve showing the decline and recovery of dissolved oxygen in a river.

Thermal pollution

A temperature change in a body of water caused by human activity.

Thermal shock

A dramatic change in water temperature that can kill aquatic organisms.

Persistence

The length of time a chemical remains in the environment.

Persistent organic pollutants (POPs)

Synthetic, carbon-based molecules that do not easily break down in the environment.

Route of exposure

The way in which an individual comes into contact with 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 food chains.

Solid waste

Any discarded material that is not a liquid or a gas.

Municipal Solid Waste (MSW)

Refuse collected by municipalities from households, small businesses, and institutions.

Waste stream

The flow of solid waste that is recycled, incinerated, or placed in a landfill.

Leachate

Liquid that contains elevated levels of pollutants as a result of passing through trash.

Sanitary Landfill

An engineered ground facility designed to hold solid waste with minimal environmental contamination.

Tipping fee

A fee charged for disposing of material in a landfill or incinerator.

Incineration

The process of burning waste materials to reduce volume and mass.

Ash

The residual nonorganic material that does not combust during incineration.

Waste-to-energy

A system in which heat generated by incineration is used as an energy source.

Hazardous waste

Liquid, solid, gaseous, or sludge waste material that is harmful to humans or ecosystems.

Superfund Act

The common name for CERCLA, a program designed to clean up hazardous waste sites., it authorized EPA to sue owners of hazardous waste sites who had illegally dumped waste

Brownfields

Contaminated industrial or commercial sites that require environmental cleanup before development.

Reduce, Reuse, Recycle (the three Rs)

A popular phrase promoting the diversion of materials from the waste stream.

Source reduction

An approach to waste management that seeks to cut waste in design and manufacture.

Reuse

Using a product or material that was intended to be discarded.

Recycling

The process by which materials are collected and converted into raw materials.

Closed-loop recycling

Recycling a product into the same product, such as aluminum cans.

Open-loop recycling

Recycling one product into a different product, such as plastic bottles into fleece.

Composting

Creation of organic matter by decomposing biodegradable waste under controlled conditions.

Life-cycle analysis (Cradle-to-grave analysis)

A systems tool that looks at the materials used and released throughout the lifetime of a product—from the procurement of raw materials through their manufacture, use, and disposal.

Integrated waste management

An approach using multiple waste disposal alternatives to reduce environmental impact.

Biochemical Oxygen Demand (BOD)

The amount of oxygen a quantity of water uses over a period of time.

Cultural Eutrophication

Overnourishment of aquatic ecosystems with plant nutrients (mostly nitrates and phosphates) because of human activities such as agriculture, urbanization, and discharges from industrial plants and sewage treatment plants.

Fecal Coliform Bacteria

A group of generally harmless microorganisms in human intestines that indicate sewage contamination.

Septic System

A small waste disposal system used for homes in rural areas.

Septic tank

A large container that receives wastewater from a house as part of a septic system.

Sludge

Solid waste material from wastewater that settles to the bottom of a septic tank.

Septage

A middle layer of fairly clear water in a septic tank.

Leach field

A component of a septic system, made of underground pipes, that filters septage.

Dose-Response study

A study that exposes organisms to different amounts of a chemical to measure effect.

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 individuals.

Sublethal effect

The effect of an environmental hazard that alters behavior, physiology, or reproduction without death.

ED50

The effective dose of a chemical that causes 50 percent of individuals to show effects.

No-observed-effect level (NOEL)

The highest concentration of a chemical in a study that causes no observable effect.

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 regulated until proven harmful.

Precautionary principle

A principle action should be taken against a potential hazard even without scientific certainty.

Stockholm convention

A 2001 agreement that produced a list of 12 chemicals to be banned, phased out, or reduced, including DDT and PCBs.

REACH

A 2007 EU agreement regulating registration, evaluation, authorization, and restriction of chemicals.

Retrospective study

A study that monitors people who have been exposed to an environmental hazard in the past.

Prospective study

A study that monitors people who might be exposed to harmful chemicals in the future.

Synergistic interaction

An interaction in which two risks together cause more harm than expected based on separate effects.

Disease

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

Infectious diseases

Diseases caused by infectious agents, known as pathogens.

Acute diseases

Diseases that rapidly impair the functioning of an organism's body.

Chronic diseases

Diseases that slowly impair the functioning of an organism's body.

Epidemic

a widespread occurrence of an infectious disease in a community at a particular time, a situation in which a pathogen causes a rapid increase in disease.

Dysentery

An inflammatory disorder of the intestine, especially of the colon, resulting in severe diarrhea.

Plague

An infectious disease caused by the bacterium Yersinia pestis, carried by fleas.

Malaria

An infectious disease caused by protists in the genus Plasmodium, transmitted by mosquitoes.

Tuberculosis

A highly contagious disease caused by the bacterium Mycobacterium tuberculosis, primarily infecting lungs.

Emerging infectious diseases

Infectious diseases that have not been common for the prior 20 years.

Acquired Immune Deficiency Syndrome (AIDS)

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

Human immunodeficiency virus (HIV)

A virus that causes AIDS by destroying helper T cells in the immune system.

Ebola Hemorrhagic fever

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

Mad cow disease

A disease in which prions mutate into deadly pathogens and damage cows' nervous systems.

Prion

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

Swine flu

A respiratory disease caused by the H1N1 virus, originating in pigs.

Bird flu

An avian influenza caused by the H5N1 virus.

Severe acute respiratory syndrome (SARS)

A type of flu caused by a coronavirus, leading to severe respiratory distress.

MERS-CoV

Middle East Respiratory Syndrome Coronavirus, first identified in Saudi Arabia in 2012.

SARS-CoV-2

The coronavirus strain that causes the respiratory disease COVID-19.

West Nile virus

A virus transmitted by mosquitoes, causing inflammation of the brain.

Lyme disease

A tick-borne illness caused by the bacterium Borrelia burgdorferi.

Zika virus disease

A disease caused by a virus transmitted primarily by Aedes mosquitoes, causing birth defects.

Clean Water Act

A US law supporting the protection and propagation of fish, shellfish, and wildlife.

Safe Drinking Water Act

(SDWA, 1974) set maximum contaminant levels for pollutants in drinking water that may have adverse effects on human health, US law setting national standards for safe tap water.

Maximum Contaminant Level (MCL)

Designation given by the U.S. Environmental Protection Agency (EPA) to drinking water standards promulgated under the Safe Drinking Water Act. It is the greatest amount of a contaminant allowed in drinking water without causing a risk to human health.

Pandemic

Disease that occurs over a wide geographic area and affects a very high proportion of the population.