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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1. Unduly rapid or throbbing heartbeat that is noted by a patient;
it may be regular or irregular.
2. Undue awareness by a patient of a heartbeat that is otherwise
paraesthesia: Abnormal sensation, as burning
paralysis: Loss or impairment of motor function.
1 Exposure of a worker's family to substances carried from the workplace
to the home.
2. Exposure of visitors to substances in the workplace.
parasympatholytic: Producing effects resembling
those caused by interruption of the parasympathetic nerve; also
Producing effects resembling those caused by stimulation of the
parasympathetic nervous system; also called cholinomimetic.
parenteral dosage: Method of introducing
substances into an organism avoiding the gastrointestinal tract
(subcutaneously, intravenously, intramuscularly etc.).
paresis: Slight or incomplete paralysis.
: Ratio of the distribution of a substance between
two phases when the heterogeneous system (of two phases) is in equilibrium;
the ratio of concentrations (or, strictly speaking, activities)
of the same molecular species in the two phases is constant at constant
temperature. The partition coefficients most frequently used in
acute toxicology are
lipid/water and octan-1-ol/water distributions.
: Inhalation of sidestream
smoke by people who do not smoke themselves.
See RT sidestream smoke
percutaneous: Through the skin following
application on the skin.
perinatal: Relating to the period shortly
before and after birth; from the twentieth to the twenty-ninth week
of gestation to one to four weeks after birth.
peritoneal dialysis: Method of artificial
detoxication in which a toxic substance from the body is transferred
into liquid that is instilled into the peritoneum. Thus, the employment
of the peritoneum surrounding the abdominal cavity as a dialysing
membrane for the purpose of removing waste products or toxins accumulated
as a result of renal failure.
peroxisome: Organelle, similar to a lysosome,
characterized by its content of catalase (EC 184.108.40.206), peroxidase
(EC 220.127.116.11) and other oxidative enzymes.
of a substance that describes the length of time that the substance
remains in a particular environment before it is physically removed
or chemically or biologically transformed.
Type of environmental monitoring in which an individual's exposure
to a substance is measured and evaluated: this is normally carried
out using a personal sampler.
RT personal sampler
Compact, portable instrument for individual air sampling, measuring,
or both, the content of a harmful substance in the respiration zone
of a working person.
SN individual monitor
pest: Organism that may harm public health,
that attacks food and other materials essential to mankind, or otherwise
affects human beings adversely.
: Strictly a substance intended
to kill pests: in common usage, any substance used for controlling,
preventing, or destroying animal, microbiological or plant pests.
NT fungicide, herbicide,
pesticide residue: Pesticide residue is any
substance or mixture of substances in food for man or animals resulting
from the use of a pesticide and includes any specified derivatives,
such as degradation and conversion products, metabolites, reaction
products and impurities considered to be of toxicological significance.
: Engulfing and digestion of
micro-organisms, other cells, and foreign particles by cells such
Drugs, medical products, medicines, or medicaments.
Process of interaction of pharmacologically active substances with
target sites, and the biochemical and physiological consequences
leading to therapeutic or adverse effects.
RT adverse effect, target,
Process of the uptake of drugs by the body, the biotransformation
they undergo, the distribution of the drugs and their metabolites
in the tissues, and the elimination of the drugs and their metabolites
from the body. Both the amounts and the concentrations of the drugs
and their metabolites are studied. The term has essentially the
same meaning as toxicokinetics, but the latter term should be restricted
to the study of substances other than drugs.
pharynx: Throat, the part of the digestive
tract between the oesophagus below and the mouth and nasal cavities
above and in front.
phase 1 reaction
: Enzymic modification of a substance
by oxidation, reduction, hydrolysis, hydration, dehydrochlorination
or other reactions catalysed by enzymes of the cytosol, of the endoplasmic
reticulum (microsomal enzymes) or of other cell organelles.
RT cytochrome P-420, cytochrome
P-448, cytochrome P-450,
2 reaction, phase 3 reaction
phase 2 reaction
: Binding of a substance, or its metabolites
from a phase 1 reaction, with endogenous molecules (conjugation),
making more water-soluble derivatives that may be excreted in the
urine or bile.
RT conjugate, phase
1 reaction, phase 3 reaction
: The observable
structural and functional characteristics of an organism determined
by its genotype and modulated by its environment.
Nagel et al. (eds), 1991
used in olfactory communication between organisms of the same species
eliciting a change in sexual or social behaviour.
SN ectohormone, feromone
: Inflammation of the skin
caused exposure to light, especially that due to metabolites formed
in the skin by photolysis.
RT photosensitization, phototoxicity
photo-oxidant: Substance able to cause oxidation
when exposed to light of the appropriate wavelength.
photophobia: Abnormal visual intolerance
Allergic reaction due to a metabolite formed by the influence of
Adverse effects produced by exposure to light energy, especially
those produced in the skin.
phytotoxic: Poisonous to plants; inhibiting
piscicide: Substance intended to kill fish.
1. Fluid component of blood in which the blood cells and platelets
SN blood plasma
2. Fluid component of semen produced by the accessory glands, the
seminal vesicles, the prostate, and the bulbo-urethral
3. Cell substance outside the nucleus.
plasmapheresis: Removal of blood from the
body and centrifuging it to obtain plasma and packed red blood cells:
the blood cells are resuspended in a physiologically compatible
solution (usually type-specific fresh frozen plasma or albumin)
and returned to the donor or injected into a patient who requires
blood cells rather than whole blood.
plasmid: Autonomous self-replicating extra-chromosomal
circular DNA molecule.
pleura: Lining of the lung.
: Term indicating the number of sets
of chromosomes present in an organism.
RT diploid, haploid
poisoning caused by absorption of lead or lead salts.
pneumonitis: Inflammation of the lung.
po: Per os - Latin for by mouth.
point mutation: Reaction that changes a single
base pair in DNA.
Single emission source in a defined location.
RT area source
: Substance that,
taken into or formed within the organism, impairs the health of
the organism and may kill it.
SN toxic substance
poison-bearing: Containing a poison.
: Morbid condition produced by a
: Any undesirable
solid, liquid or gaseous matter in a solid, liquid or gaseous environmental
medium: "undesirability" is often concentration-dependent, low concentrations
of most substances being tolerable or even essential in many cases.
For the meaning of "undesirable" in air pollution contexts, see
"pollution". A primary pollutant is one
emitted into the atmosphere, water, sediments or soil from an identifiable
source. A secondary pollutant is a pollutant formed by chemical
reaction in the atmosphere, water, sediments, or soil.
RT pollution, secondary
After WHO, 1980
of pollutants into a solid, liquid, or gaseous environmental medium,
the presence of pollutants in a solid, liquid, or gaseous environmental
medium, or any undesirable modification of the composition of a
solid, liquid or gaseous environmental medium. In the context of
air pollution, an undesirable modification is one that has injurious
or deleterious effects.
RT contaminant, pollutant
polydipsia: Chronic excessive thirst.
Interindividual variations in metabolism of endo-
and exogenous compounds due to genetic influences, leading to enhanced
side effects or toxicity of drugs (for example, poor versus fast
metabolizers) or to different clinical effects (metabolism of steroid
RT ecogenetics, pharmacogenetics,
polyuria: Excessive production and discharge
: In statistics, the totality of
items under consideration. A clearly defined part of a population
is called a subpopulation. In the case of a random variable, the
probability distribution is considered as defining the population
of that variable. The term "population segment" is sometimes used
as a synonym for subpopulation.
: Number of persons who can and may develop an adverse health
effect and who are potentially exposed to a risk factor under study:
for example, all people in a population who have not developed immunity
to an infectious disease are at risk of developing that disease
if they are exposed to it. People already having chronic disease
are excluded from the population at risk in studies of the incidence
of the disease.
After WHO, 1979
population critical concentration (PCC):
of a substance in the critical organ at which a specified percentage
of the exposed population has reached the individual critical organ
concentration. The percentage indicated by PCC-10 for 10 %, PCC-50
for 50 % etc. (similar to the use of the term LD50
Kjellstrom et al., 1984
population effect: Absolute number or incidence
rate of cases occurring in a group of people.
porphyria: Disturbance of porphyrin metabolism
characterized by increased formation, accumulation, and excretion
of porphyrins and their precursors.
: Study of dose in relation to the
physiological factors that may influence response such as age of
the exposed organisms.
potency: Expression of chemical or medicinal
activity of a substance as compared to a given or implied standard
Dependent action in which a substance or physical agent at a concentration
or dose that does not itself have an adverse effect enhances the
harm done by another substance or physical agent.
RT additive effect, antagonism,
: Numerically specified low risk of exposure to a
potentially toxic substance (for example, 1 in 106) or socially
acceptable low risk of adverse effects from such an exposure applied
to decision making
in regard to chemical safety.
RT risk, safety
After Duffus, 1986
precordial: Pertaining to the region over
the heart and lower thorax.
precursor: Substance from which another,
usually more biologically active, substance is formed.
: Reliability of a measurement expressed in terms of
its ability to predict the criterion: an example would be an academic
aptitude test that was validated against subsequent academic performance.
preneoplastic: Before the formation of a
: Number of instances of existing
cases of a given disease or other condition in a given population
at a designated time; sometimes used to mean prevalence rate. When
used without qualification, the term usually refers to the situation
at a specified point in time (point prevalence).
prevalence rate (ratio)
: Total number of
individuals who have an attribute or disease at a particular time
(or during a particular period) divided by the population at risk
of having the attribute or disease at this point in time or midway
through the period.
RT population at risk
primary protection standard
: Accepted maximum
level of a pollutant (or its indicator) in the target organism,
or some part thereof, or an accepted maximum intake of a pollutant
or nuisance into the target under specified circumstances.
probit: Probability unit obtained by adding
5 to the normal deviates of a standardized normal distribution of
results from a dose response study: addition of 5 removes the complication
of handling negative values. A plot of probit against the logarithm
of dose or concentration gives a linear plot if the distribution
of response is a logarithmic normal one. Estimates of the LD50
and ED50 (or LC50 and EC50) can
be obtained from this plot.
procarcinogen: Substance that has to be metabolized
before it can induce malignant tumours.
organism, characterised by the absence of a membrane-enclosed nucleus.
Prokaryotes include bacteria, blue-green algae and mycoplasmas.
After Nagel et al. (eds),
promoter (in oncology)
Agent that induces cancer when administered to an animal or human
being who has been exposed to a cancer initiator.
proportional mortality rate (ratio) (PMR)
Number of deaths from a given cause in a specified time period,
per 100 or per 1000 total deaths in the same time period: can give
rise to misleading conclusions if used to compare mortality experience
of populations with different causes of death.
of excessive amounts of protein (derived from blood plasma or kidney
tubules) in the urine.
Apparent adaptation of an organism to changing conditions of the
environment (especially chemical) associated with stresses in biochemical
systems that exceed the limits of normal (homeostatic) mechanisms:
essentially there is a temporary concealed pathology that later
on can be manifested in the form of explicit pathological changes
sometimes referred to as "decompensation."
psychosis: Any major mental disorder characterized
by derangement of the personality and loss of contact with reality.
psychotropic: Exerting an effect upon the
mind; capable of modifying mental activity.
public health impact assessment
risk assessment to a specific target population of known size, giving
as the end product a quantitative statement about the number of
people likely to be affected in a particular population.
BT risk assessment
pulmonary: Pertaining to the lungs.
pyrexia: Condition in which the temperature
of a human being or mammal is above normal.
pyrogen: Any substance that produces fever.
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