Environmental Science Hit Parade: Chapter 8

Front 1

acute effect

Back 1

the effect caused by a short exposure to a high level of toxin.

Front 2

catalytic converter

Back 2

a platinum-coated device that oxidizes most of the VOCs and some of the CO that would otherwise be emitted in exhaust, converting them to CO2.

Front 3

closed-loop recycling

Back 3

when materials, such as plastic or aluminum, are used to rebuild the same product. An example of this is the use of the aluminum from aluminum cans to produce more aluminum cans.

Front 4

composting

Back 4

a process that allows the organic matter in sold waste to be decomposed and reintroduced into the soil, often as fertilizer.

Front 5

chronic effect

Back 5

an effect that results from the long-term exposure to low levels of toxin.

Front 6

deep well injection

Back 6

drilling a hole in the ground that's below the water table to hold waste.

Front 7

disease

Back 7

occurs when infection causes a change in the state of health.

Front 8

dose-response analysis

Back 8

a process in which an organism is exposed to a toxin at different concentrations, and the dosage that causes the death of the organism is recorded.

Front 9

ED50

Back 9

the point at which 50 percent of the test organisms show a negative effect from a toxin.

Front 10

gray smog (industrial smog)

Back 10

smog resulting from emissions from industry and other sources of gases produced by the burning of fossil fuels, especially coal.

Front 11

infection

Back 11

the result of a pathogen invading a body.

Front 12

LD50

Back 12

the point at which 50 percent of the test organisms die from a toxin.

Front 13

leachate

Back 13

the liquid that percolates to the bottom of a landfill.

Front 14

open-loop recycling

Back 14

when materials are reused to form new products.

Front 15

ozone holes

Back 15

the thinning of the ozone layer over Antarctica(and to some extent, over the Arctic)

Front 16

pathogens

Back 16

bacteria, virus, or other microorganisms that can cause disease.

Front 17

photochemical smog

Back 17

when photochemical smog, NOx compounds, VOCs, and ozone combine to form smog with a brownish hue.

Front 18

poison

Back 18

any substance that has an LD50 of 50 mg or less per kg of body weight.

Front 19

physical treatment

Back 19

in a sewage treatment plant, the initial filtration that is done to remove debris such as stones, sticks, rags, toys, and other objects that were flushed down the toilet.

Front 20

primary pollutants

Back 20

pollutants that are released directly into the lower atmosphere.

Front 21

primary treatment

Back 21

when physically treated sewage water is passed into a settling tank, where suspended solids settle out as sludge; chemically treated polymers may be added to help the suspended solids separate and settle out.

Front 22

secondary pollutants

Back 22

pollutants that are formed by the combination of primary pollutants in the atmosphere.

Front 23

secondary treatment

Back 23

the biological treatment of wastewater in order to continue to remove biodegradable waste.

Front 24

sludge

Back 24

the solids that remain after the secondary treatment of sewage.

Front 25

sludge processor

Back 25

a tank filled with aerobic bacteria that's used to treat sewage.

Front 26

Superfund Program

Back 26

a program funded by the federal government and a trust that's funded by taxes on chemicals; identifies pollutants and cleans up hazardous waste sites.

Front 27

threshold dose

Back 27

the dosage level of a toxin at which a negative effect occurs.

Front 28

toxin

Back 28

any substance that is inhaled, ingested, or absorbed at dosages sufficient to damage a living organism.

Front 29

U.S. Noise Control Act

Back 29

gave the EPA power to set emission standards for major sources of noise, including transportation, machinery, and construction.

Front 30

vector

Back 30

the carrier organism through which pathogens can attack.

Front 31

green tax

Back 31

a fiscal policy that lowers taxes on income, including wages and profit, and raises taxes on consumption, particularly the unsustainable consumption of non-renewable resources.

Front 32

market permits

Back 32

when companies are allowed to buy permits that allow them a certain amount of discharge of substances into certain environmental outlets. If they can reduce their amount of discharge, they are allowed to sell the remaining portion of their permit to another company.