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Acute Toxicity- adverse effects resulting from a single exposure or dose of a chemical; immediate effect

Antibiotic- A chemical substance, produced by a microorganism, which has the capacity, in low concentrations, to inhibit or even destroy bacteria and other microorganisms. The definition may be expanded to include higher plants as a source.

Bioaccumulation- the process which results in increasing body burdens of recalcitrant non-water soluble compounds as they move up the food chain.

Biodiversity- the number and variety of different organisms in the particular ecological setting.

Carrier- one who harbours a disease organism but does not have the symptoms.

Chemotherapy- the use of a drug, or combination of drugs, to kill or inhibit the growth of microorganisms or cancer.

Chronic effect- adverse effects in which symptoms develop slowly over a period of time and with multiple low doses.

Climate change-refers to the consequences of the buildup of anthropogenic gases in the atmosphere which trap the sun's heat, causing changes in the weather pattern on a global scale.

Climax Community- the relative stable community reached by a successional series.

Community- all the organisms of a given taxonomic rank (ie animal, plant, microbial community). Also applied to geographical regions (biomes) as in a tundra community or salt marsh community.


Dose Response- change in response of organisms related to changes in overall exposure to substance.

Ecological Succession- the gradual process by which species composition of an ecosystem change.

Ecosystem- the interaction of all living organisms in a particular environment.

Forest Management- strategy, in theory, that reconciles the economic interests of producers with the needs of conservation.

Food Chain- the trophic interrelationship of species within an ecosystem.

Gaia hypothesis- postulates that the earth behaves like a living organism with living things and the environment evolving together..each affecting the other.

"Green Labeling"- certification programs calling for voluntary compliance with established environmental standards in exchange for higher prices or greater market access, or both.


Host- an organism in which another organism spends part or all of its life cycle.


Infectious- capable of spreading from individual to individual by a variety of routes.


Mutagenic Compounds- compounds or processes which interact with genetic material directly or indirectly resulting in alteration of the base sequence.

Maximum Sustainable Yield- the maximum amount which can be harvested without reducing the stock which is available in subsequent years.


Niche- role and association of a particular species in the community.


Opportunistic pathogen- organisms that can cause disease only when the bodily defenses are suppressed.

Pathogen- an organism (including viruses, virions and prions) capable of causing disease.

Pharmacognosy- an applied science which deals with the biologic, biochemical, and economic features of natural drugs and their constituents. It is the study of drugs having their origin in the plant and animal kingdom.

Population- all the members of a given species in a particular region.

Primary Productivity- the basis of all food chains, the production at the lowest level of the food chain...usually photosynthesis.


Recalcitrant Molecules- molecules which are not readily degraded under normal environmental conditions.

Structure-activity relationship- the influence of structural features, such as the conformation of the drug molecule and optical and geometric isomerism, on the pharmacologic activity of the drug molecule.

Sustainable- (agriculture, logging, manufacturing, etc.) environmentally friendly methods that allow the continued production of a commodity without damage to the ecosystem. Includes soil, water supplies, biodiversity or other surrounding resources.

Synergism- an interaction in which the effects of two in combination is greater than the sum of the singular effects.

Synthetic- compounds produced by total synthesis from unrelated and base reactants.

Semi-Synthetic- compounds produced by a chemical modification of a natural product.


Teratogenic compounds- compounds which have profound effects on developmental stages of an organism.

Toxic chemical- substances that can cause severe illness, poisoning, birth defects, disease or death when ingested, inhaled or absorbed by organisms.

Toxic molecules- molecules which result in abnormal physiological, metabolic or developmental function.

Toxicity Characteristic Leaching Procedure (TCLP)- test to determine when a waste is hazardous or requires treatment to become less hazardous; useful in monitoring treatment techniques.


Vaccine- an immunization procedure usually involving an injection