IUPAC Glossary of Terms Used in Toxicology – Terms Starting with F
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fecundity
- Ability to produce offspring frequently and in large numbers.
- In demography, the physiological ability to reproduce.
- Ability to produce offspring within a given period of
time.
[8]
feromone
ectohormone
pheromone
Substance used in olfactory communication between organisms of
the same species eliciting a change in sexual or social
behavior.
fertility
Ability to conceive and to produce offspring: for litter-bearing
species the number of offspring per litter is used as a measure
of fertility.
Note: Reduced fertility is sometimes referred to as
subfertility.
fertility toxicant
Produces abnormalities of male or female reproductive functions
or impairs reproductive capacity.
fertilizer
Substance applied to soil or hydroponic systems for improving the
root nutrition of plants with the aim of increasing crop yields
and (or) controlling production.
fetal period
See fetus
fetotoxicity
Toxicity
to the fetus.
fetus (often incorrectly
foetus)
Young mammal within the uterus of the mother from the visible
completion of characteristic organogenesis until birth.
Note: In humans, this period is usually defined as from the third
month after fertilization until birth (prior to this, the young
mammal is referred to as an embryo).
fibrosis
Abnormal formation of fibrous tissue.
fiducial limit
Form of confidence limit given as a stated probability, for
example P = 0.95.
Note: In toxicology the terms fiducial limits and confidence
limits are generally considered to be synonymous.
first-order reaction
- Chemical reaction where the initial rate is directly
proportional to the concentration
of one of the reactants.
[2] - Any process in which a variable decreases with time at a
constant fractional amount.
[2]
first-pass effect
Biotransformation
and, in some cases, elimination
of a substance in the liver after absorption
from the intestine and before it reaches the systemic
circulation.
[2]
first-pass metabolism
See first-pass effect
fixed dose procedure
Acute toxicity
test in which a substance is tested initially at a small number
(3 or 4) predefined doses to identify
which produces evident toxicity without lethality: the test may
be repeated at one or more higher or lower defined discriminating
doses to satisfy the criteria.
fluoridosis
See fluorosis
fluorosis
fluoridosis
Adverse
effects of
fluoride, as in dental or skeletal fluorosis.
Flow rate of an entity through a cross-section perpendicular to the flow divided by the cross-sectional area.
foci (singular focus)
in neoplasia
Small groups of cells distinguishable, in appearance or
histochemically, from the surrounding tissue: indicative of an
early stage of a lesion that may lead to the formation of a
neoplastic nodule.
foetus
See fetus
follow-up study
See cohort
study
food additive
Any substance, not normally consumed as a food by itself and not
normally used as a typical ingredient of a given food, whether or
not it has nutritive value, that is added intentionally to food
for a technological (including organoleptic) purpose in the
manufacture, processing, preparation, treatment, packing,
packaging, transport or holding of the food. Addition results, or
may be reasonably expected to result (directly or indirectly), in
the substance or its byproducts becoming a component of, or
otherwise affecting, the characteristics of the food to which it
is added.
Note: The term does not include “contaminants” or
substances added to food for maintaining or improving nutritional
qualities.
food allergy
Hypersensitivity
reaction to substances in the diet to which an individual has
previously been sensitized.
food chain
Sequence of transfer of matter and energy in the form of food
from organism to organism in ascending or descending trophic
levels.
food intolerance
Physiologically based reproducible, unpleasant (adverse) reaction
to a specific food or food ingredient that is not immunologically
based.
food web
Network of food chains.
forced diuresis
Method of stimulating diuresis based on performing hydrational
therapy, sometimes with parallel introduction of diuretics, with
the aim of achieving increased clearance of a toxic
substance in urine.
foreign substance
See xenobiotic
founder effect
Changes in allelic frequencies that occur when a small group is
separated from a large population and establishes a colony in a
new location.
[9]
fractionation
Process of classification of an analyte or a group of analytes
from a sample according to physical (e.g. size,
solubility) or chemical (e.g. bonding, reactivity)
properties.
[2]
frame-shift mutation
Point mutation
involving either the deletion or insertion of one or two
nucleotides in a gene: by the frame shift mutation, the
normal reading frame used when decoding nucleotide triplets in
the gene is altered.
fumigant
Substance that is vaporized in order to kill or repel pests.
functional genomics
Development and implementation of technologies to characterize
the mechanisms through which genes and
their products function and interact with each other and with the
environment.
[9]
fungicide
Substance intended to kill fungi.
fungus preparation
Substance obtained from fungi that has an insecticidal effect
reflecting the pathogenicity of the fungi for insects.