Absorbed dose

 the amount of a chemical that enters the body of an exposed organism

the normal ambient environmental concentration of a chemical        

 Cancer

 a disease characterized by the uncontrolled growth of aberrant cells into malignant tumors

Carcinogen 

 a chemical causes cancer

 Carcinogenic potency

  the estimated risk of cancer per unit of absorbed dose

Dermal 

 referring to the skin, through or by the skin

Dose response 

 a quantitative relationship between the dose of a chemical and an effect cased by the chemical

Environmental fate

 the destiny of a chemical after its release to the environment and in consideration of factors such as transport through air, soil and water, bioconcentration and degradation

Epidemiological study

  the investigation of elements that contribute to disease or toxic effects in human populations

Exposure

 contact with a chemical or physical agent

Exposure assessment 

 the determination or estimation (qualitative or quantitative) or the magnitude, frequency, duration, route, and extent (number of people) of exposure to a substance.

Exposure level 

  the amount (concentration) of a substance at the absorptive surface of an organism

Exposure scenario

 a set of conditions or assumptions regarding sources, exposure pathways, concentrations of toxic chemicals, and populations (numbers, characteristics and habits) that are used to assist the investigator in evaluating and quantifying exposure

Extrapolation

 the estimation of unknown values through the extension or projection of known values

Half-life 

 the length of time required for the mass, concentration, or activity of a chemical or physical agent to be reduced by one half

Ingestion 

 the act of taking in through the mouth

Metabolism 

  the sum of the chemical reactions that occur within a cell or a whole organism, including the energy-releasing breakdown of molecules and the synthesis of new molecules

Metabolite

 any product of metabolism, especially a transformed chemical

Modeling 

  the use of mathematical equations to simulate and predict real events and processes

Monitoring 

 the measure of concentrations of substances in environmental media or in human or other biological tissues.

Mutagenicity

 the capacity of a chemical or physical agent to cause permanent alteration of the genetic material within living cells

NOAEL 

 (no observe adverse effect level) the highest dose in an experiment that did not produce an observable effect

Oral 

 referring to the mouth, through or by the mouth

Population at risk

  a population subgroup that is more likely to be exposed to a substance or more sensitive to a substance than the general population

Receptor 

 in an exposure assessment, an organism that receives, may receive, or has received environmental exposure to a chemical

Reference dose 

 the USEPA's preferred toxicity value of a daily exposure level for the human population that is likely to be without an appreciable risk of deleterious effects during a lifetime

Risk

 the potential for negative consequences or events

Risk assessment

  a qualitative or quantitative evaluation of the environmental and/or health risk resulting from exposure to a chemical or physical agent (pollutant), combines exposure assessment results with toxicity assessment results to estimate risk.

Risk estimate

  a description of the probability that organisms exposed to a specified dose of chemical will develop an adverse response

Risk factor 

  characteristic (race, sex, age, obesity) or variable (smoking, occupational exposure level) associated with the increased probability of an adverse effect.

Route of exposure 

 the avenue by which a chemical gains access to the body (inhalation, ingestion, dermal contact)

Slope factor 

 the estimated increased lifetime risk of cancer per unit of absorbed dose

Threshold

 the lowest dose of a chemical at which a specified measurable effect is observed and below which it is not observed

Toxicity

 the quality or degree of being poisonous or harmful to plant, animal or human life

Toxicity assessment

 the characterization of the toxicological properties and effects of a chemical, including all aspects of its absorption, metabolism, excretion and mechanism of action with special emphasis on establishment of dose-response characteristics

Uncertainly factor

 a number (equal to or greater than one) used to divide NOAEL or LOAEL values derived from measurements in animal or small groups of humans in order to estimate a NOAEL value for the whole human population.