Toxicology Glossary - F
fecundity:- Ability to produce offspring frequently and in large numbers.
- In demography, the physiological ability to reproduce.
feromone: See SN pheromone.
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. Reduced fertility is sometimes referred to as subfertility.
USEPA, 1989
RT fecundity
fertility toxicant: Produces abnormalities of male or female reproductive functions or impairs reproductive capacity.
RT developmental toxicity, reproductive toxicant.
USEPA, 1986
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.
fetotoxicity:Toxicity to the fetus.
RT embryotoxicity, teratogenicity.
fetus (often incorrectly foetus): Young mammal within the uterus of the mother from the visible completion of characteristic organogenesis until birth: in humans, this period is usually defined as from the third month after fertilisation until birth (prior to this, the young mammal is referred to as an embryo).
RT embryo.
Oxford English Dictionary, 1991
fibrosis: Abnormal formation of fibrous tissue.
fiducial limit: Form of confidence limit given as a stated probability, for example P = 0.95: in toxicology the terms fiducial limits and confidence limits are generally considered to be synonymous.
Brown, 1988
first-pass effect: Biotransformation of a substance in the liver after absorption from the intestine and before it reaches the systemic circulation.
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.
NT limit test.
fluorosis: Adverse effects of fluoride, as in dental or skeletal fluorosis.
foci (singular focus): 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:Investigation in which individuals or populations, selected on the basis of whether they have been exposed to risk, have received a specified preventive or therapeutic procedure, or possess a certain characteristic, are followed to assess the outcome of exposure, the procedure, or effect of the characteristic, for example, occurrence
of disease.
SN cohort study.
Last, 1988
food additive: Any substance not normally consumed as a food by itself and not normally used as a typical ingredient of the food, whether or not it has nutritive value, the intentional addition of which to food for a technological (including organoleptic) purpose in the manufacture, processing, preparation, treatment, packing, packaging, transport or holding
of such food results, or may be reasonably expected to result (directly or indirectly) in it or its byproducts becoming a component of or otherwise affecting the characteristics of such foods. The term does not include "contaminants" or substances added to food for maintaining or improving nutritional qualities.
Codex Alimentarius Commission, 1983
food allergy: Hypersensitivity reaction to substances in the diet to which an individual has previously been sensitised.
BT allergy, hypersensitivity.
RCP, 1984
food chain: Sequence of transfer of matter and energy in the form of food from organism to organism in ascending or descending trophic levels.
WHO, 1979
food intolerance: Physiologically based reproducible, unpleasant (adverse) reaction to a specific food or food ingredient that is not immunologically based.
RCP, 1984
RT food allergy.
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 rine.
foreign substance (foreign compound): See SN xenobiotic.
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.
After Nagel et al. (eds), 1991
fumigant: Substance that is vaporized in order to kill or repel pests.
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.
IRPTC, 1982