Organizations & People
Pure Appl. Chem.,
Vol. 65, No. 9, pp. 2003-2122, 1993.
COMMISSION ON TOXICOLOGY
Glossary for chemists of terms used in toxicology
(IUPAC Recommmendations 1993)
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ecology: Branch of biology which studies
the interactions between living organisms and all factors (including
other organisms) in their environment: such interactions encompass
environmental factors which determine the distributions of living
of organisms (micro-organisms, plants, animals) interacting together,
with and through their physical and chemical environments, to form
a functional entity.
ecotoxicology: Study of the toxic effects
of chemical and physical agents on all living organisms, especially
on populations and communities within defined ecosystems; it includes
transfer pathways of these agents and their interactions with the
: Substance intended to kill
parasites living on the exterior of the host.
eczema: Acute or chronic skin inflammation
with erythema, papules, vesicles, pustules, scales, crusts or scabs,
alone or in combination, of varied aetiology.
: Concentration of a substance that causes
a defined magnitude of response in a given system: EC50 is the median
concentration that causes 50 % of maximal response.
RT lethal concentration
effective dose (ED):
Dose of a substance that causes a defined magnitude of response
in a given system: ED50 is the median dose that causes 50 % of maximal
RT lethal dose
: Fluid, solid
or gas discharged from a given source into the external environment.
of a substance or other material from an organism (or a defined
part thereof), usually by a process of extrusion or exclusion, sometimes
after metabolic transformation.
eliminator (of a poison): Substance that
contributes to the elimination of a poison from an organism.
1. Stage in the developing mammal at which the characteristic organs
and organ systems are being formed: for humans, this
involves the stages of development from the second
to the eighth week (inclusive post conception).
2. In birds, the stage of development from the fertilization of
the ovum up to hatching.
3. In plants, the stage of development within the seed.
1. Production by a substance of toxic effects in progeny in the
first period of pregnancy between conception and the fetal
2. Any toxic effect on the conceptus as a result of prenatal exposure
during the embryonic stages of development: these
effects may include malformations and variations, malfunctions,
altered growth, prenatal death, and altered postnatal
After USEPA, 1989
RT developmental toxicity,
embryotropic effect: Change in the embryo
and the regulation of its development.
of a substance from a source, including discharges to the wider
SN discharge, effluent,
and exposure control
: Technical and administrative procedures
and specifications applied for the monitoring, reduction or elimination
of emissions from a source or exposure to a target.
After WHO, 1989a
: Quantitative limit on
the emission or discharge of a substance from a source, usually
expressed in terms of a time-weighted average concentration or a
RT limit value
endemic: Present in a community or among
a group of people; said of a disease prevailing continually in a
endocrine: Pertaining to hormones or to the
glands that secrete hormones directly into the bloodstream.
endothelial: Pertaining to the layer of flat
cells lining the inner surface of blood and lymphatic vessels, and
the surface lining of serous and synovial membranes.
enteritis: Intestinal inflammation.
: Cyclical process
involving intestinal re-absorption of a substance that has been
excreted through the bile followed by transfer back to the liver,
making it available for biliary excretion again.
After WHO, 1979
: Aggregate, at a given moment,
of all external conditions and influences to which a system under
study is subjected.
environmental damage: Adverse effects to
the natural environment.
environmental exposure level (EEL): Level
(concentration or amount or a time integral of either) of a substance
to which an organism or other component of the environment is exposed
in its natural surroundings.
environmental fate: Destiny of a chemical
or biological pollutant after release into the natural environment.
environmental health impact assessment: Estimate
of the adverse health effects or risks likely to follow from a proposed
or expected environmental change or development.
environmental health criteria documents:
Critical publications of IPCS containing reviews of methodologies
and existing knowledge - expressed, if possible, in quantitative
terms - of selected substances (or groups of substances) on identifiable,
immediate, and long-term effects on human health and welfare.
: Practical control measures used to improve the basic
environmental conditions affecting human health, for example clean
water supply, human and animal waste disposal, protection of food
from biological contamination, and housing conditions, all of which
are concerned with the quality of the human environment.
After WHO, 1979
SN environmental sanitation
impact assessment (EIA)
: Appraisal of the possible environmental
consequences of a past, ongoing, or planned action, resulting in
the production of an environmental impact statement or "finding
of no significant impact (FONSI)".
RT environmental impact
: Continuous or repeated measurement of agents in
the environment to evaluate environmental exposure and possible
damage by comparison with appropriate reference values based on
knowledge of the probable relationship between ambient exposure
and resultant adverse effects.
RT biological effect
monitoring, reference value
1. Actions taken to prevent or minimize adverse effects to the natural
2. Complex of measures including monitoring of environmental pollution,
development and practice of environmental
protection principles (legal, technical, and hygienic),
including risk assessment, risk management and risk
environmental quality objective (EQO)
state to be aimed for in a particular aspect of the natural environment,
for example, "water in an estuary such that shellfish populations
survive in good health". Unlike an environmental quality standard,
the EQO is usually expressed in qualitative and not quantitative
RT environmental quality
quality standard (EQS)
: Amount concentration or mass concentration
of a substance that should not be exceeded in an environmental system,
often expressed as a time-weighted average measurement over a defined
SN ambient standard
RT limit value
environmental transformation: Chemical transformation
of substances resulting from interactions in the environment.
enzootic: Present in a community or among
a group of animals; said of a disease prevailing continually in
Study of the distribution and determinants of health-related states
or events in populations and the application of this study to control
of health problems.
epigastric: Pertaining to the upper-middle
region of the abdomen.
in an organism brought about by alterations in the expression of
genetic information without any change in the genome itself: the
genotype is unaffected by such a change but the phenotype is altered.
RT mutation, phenotype,
epileptiform: Occurring in severe or sudden
spasms, as in convulsion or epilepsy.
tumour derived from epithelium.
epithelium: Cells covering the internal and
external surfaces of the body.
: Any part of
a molecule that acts as an antigenic determinant: a macromolecule
can contain many different epitopes each capable of stimulating
production of a different specific antibody.
Nagel et al. (eds), 1991
equivalent diameter (of a particle)
of a spherical particle of the same density as a particle under
investigation that, relative to a given phenomenon or property,
would behave in the same way as the particle under investigation.
RT aerodynamic diameter
erythema: Redness of the skin produced by
congestion of the capillaries.
eschar: Slough or dry scab on an area of
skin that has been burnt.
estimated daily intake (EDI)
of the daily intake of a residue of a potentially harmful agent
based on the most realistic estimation of the residue levels in
food and the best available food consumption data for a specific
population: residue levels are estimated taking into account known
uses of the agent, the range of contaminated commodities, the proportion
of a commodity treated, and the quantity of home-grown or imported
commodities. The EDI is expressed in mg residue per person.
estimated exposure concentration (EEC): Measured
or calculated amount or mass concentration of a substance to which
an organism is likely to be exposed, considering exposure by all
sources and routes.
estimated exposure dose (EED)
: Measured or
calculated dose of a substance to which an organism is likely to
be exposed, considering exposure by all sources and routes.
estimated maximum daily intake (EMDI)
of the maximum daily intake of a residue of a potentially harmful
agent based on assumptions of average food consumption per person
and maximum residues in the edible portion of a commodity, corrected
for the reduction or increase in residues resulting from preparation,
cooking, or commercial processing. The EMDI is expressed in mg residue
: Cell or
organism with the genetic material packed in a membrane-surrounded
structurally discrete nucleus and with well-developed cell organelles.
The term includes all organisms except archaebacteria, eubacteria
and cyanobacteria (until recently classified as cyanophyta or blue-green
Nagel et al. (eds), 1991
European Inventory of Existing Chemical Substances
(EINECS): List of all substances supplied either singly or as
components in preparations to persons in a Member State of the European
Community on any occasion between 1 January 1971 and 18 September
eutrophic: Describes a body of water with
a high concentration of nutrient salts and a high or excessive rate
of biological production.
eutrophication: Adverse change in the chemical
and biological status of a body of water following depletion of
the oxygen content caused by decay of organic matter resulting from
high primary production as a result of enhanced input of nutrients.
: Additional or excess risk incurred over the lifetime of
an individual by exposure to a toxic substance.
Method of active artificial elimination of toxicity consisting in
complete replacement of blood of the patient by donor blood.
: Any more
or less inert substance added to a drug to give suitable consistency
or form to the drug.
: Discharge or elimination of an
absorbed or endogenous substance, or of a waste product, and/or
their metabolites, through some tissue of the body and its appearance
in urine, faeces, or other products normally leaving the body. Excretion
of chemical compounds from the body occurs mainly through the kidney
and the gut. Volatile compounds may be largely
eliminated by exhalation. Excretion by perspiration and through
hair and nails may also occur. Excretion by the gastrointestinal
tract may take place by various routes such as the bile, the shedding
of intestinal cells and transport through the intestinal mucosa.
After WHO, 1989a
RT clearance, elimination
excretion rate: Amount of substance (and/or
its metabolites) or fraction that is excreted per unit time. It
should be noted that according to this definition excretion does
not include the passing of a substance through the intestine without
absorption. When discussing the total amount of a substance in faeces
(including the unabsorbed part), it is preferable to
speak about faecal substance content (mol/kg) or mass content (kg/kg).
from causes or derived from materials external to an organism.
: See SN microcosm
explant: Living tissue removed from its normal
environment and transferred to an artificial medium for growth.
exposed: Subject to a factor that is under
study in the environment, for instance an environmental hazard.
AN non-exposed, unexposed.
exposed group (sometimes abbreviated to exposed)
Group whose members have been exposed to a
supposed cause of a disease or health state of interest, or possess
a characteristic that is a determinant of the health outcome of
1. Concentration, amount or intensity of a particular physical or
chemical agent or environmental agent that reaches the
target population, organism, organ, tissue or cell,
usually expressed in numerical terms of substance concentration,
uration, and frequency (for chemical agents and micro-organisms)
or intensity (for physical agents such as radiation).
2. Process by which a substance becomes available for absorption
by the target population, organism, organ, tissue or cell,
by any route.
Process of measuring or estimating concentration (or intensity),
duration and frequency of exposures to an agent present in the environment
or, if estimating hypothetical exposures, that might arise from
the release of a substance, or radionuclide, into the environment.
RT risk assessment
General term defining an administrative substance concentration
or intensity of exposure that should not be exceeded.
RT discharge limit
: In a case control study,
value obtained by dividing the rate at which persons in the case
group are exposed to the risk factor (or to the protective factor)
by the rate at which persons in the control group are exposed to
the risk factor (or to the protective factor) of interest.
After Last, 1988
: Determination of the level,
concentration or uptake of a potentially toxic compound and/or its
metabolite(s) in biological samples from an organism (blood, urine,
hair etc.) and the interpretation of the results to estimate the
absorbed dose or degree of environmental pollution; or the measuring
of biochemical effects, usually not direct adverse effects of the
substance, and relating them to the quantity of substance absorbed,
or to its concentration in the environment.
RT biological monitoring,
Generalizability of the results of a particular study, beyond the
limits of the population actually studied.
that an agent produces an observed response, as distinguished from
the probability that the response is caused by a spontaneous event
unrelated to the agent.
extraneous residue limit (ERL)
: Refers to
a pesticide residue or contaminant arising from environmental sources
(including former agricultural uses) other than the use of a pesticide
or contaminant substance directly or indirectly on the commodity.
It is the maximum concentration of a pesticide residue or contaminant
that is recommended by the Codex Alimentarius Commission to be legally
permitted or recognized as acceptable in or on food, agricultural
commodity or animal feed. The mass content is expressed in milligrams
of pesticide residue or contaminant per kilogram of commodity.
Codex Alimentarius Commission, 1986
extrapolation: Calculation, based on quantitative
observations in exposed test species or in vitro test systems,
of predicted dose-effect and dose-response relationships for a substance
in humans and other biota including interspecies extrapolations
and extrapolation to susceptible groups of individuals: the term
may also be used for qualitative information applied to species
or conditions that are different from the ones in which the original
investigations were carried out.
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