[A]
[B] [C] [D]
[E] [F] [G]
[H] [I-J-K] [L]
[M-N] [O-P] [Q-R]
[S] [T] [U-V]
[W-X-Y-Z]
carrier Solid formulant
added to a technical material as an absorbent or diluent.
(FAO, 1995)
carryover (analytical) Unintended
contamination of a sample undergoing analysis with material from a previous
sample.
carryover (field) Persistence of pesticide
residues in soil after use in one crop such that uptake is observed in a succeeding,
possibly more sensitive, crop.
catabolism Oxidative biodegradation
of a pesticide to provide chemically available energy and generate metabolic
intermediates. (after IUPAC, 1992)
catchment Land and water confined
within a single drainage basin.
certified reference material Reference
material, accompanied by a certificate, whose pesticide concentrations
are certified by procedures which establish their traceability and for
which each certified concentration is accompanied by an uncertainty
at a stated level of confidence. Storage conditions and period for which
the certification remains valid may also be included for unstable materials.
(after Thompson and Woods, 1995)
chronic effect Consequence of exposure
to a pesticide which arises slowly and has a long-lasting, often irreversible,
course. (after Duffus, 1993)
chronic exposure Continued
exposures occurring over an extended period of time, or a significant fraction
of the lifetime of the exposed individuals or test species. (after Duffus,
1993)
chronic toxicity Capacity
for a pesticide to produce injury following chronic exposure or to
produce effects which persist whether or not they occur immediately upon exposure
or are delayed. (after Duffus, 1993)
co-metabolism Microbial metabolism
of a pesticide where the derived energy is not used to support microbial
growth. Cf. catabolism.
common moiety Molecular sub-unit which
is common to the structures of several pesticides or metabolites.
community Assembly of populations
of different species of living organisms (quite often interdependent
on and interacting with each other) within a specified location in space
and time. See also ecosystem. (US-EPA,
1992)
compartment Part of an organism or
ecosystem considered as an independent
system for purposes of assessment of uptake, distribution and dissipation
of a pesticide. (US-EPA, 1992)
compliance (GLP) See GLP compliance
statement.
compliance (residue) Meeting
of official maximum residue limit
(MRL) standards by residue levels in food consignments sampled
and tested by approved methods.
composite sample Combined increment
samples, or combined replicate samples, or combined samples from
replicate trials. Preferred term to bulk sample which is ambiguous.
(Horwitz, 1990). See also aggregate sample,
primary sample.
concentration-effect relationship
Association between the exposure concentration of the pesticide
and the magnitude of the resultant continuously graded change either in an
individual organism or in a population. (after Duffus, 1993)
conjugation Biosynthetic reaction
in which a pesticide or its metabolite is linked to an endogenous compound.
See also endocon, exocon,
phase II metabolism.
contaminant
1. Minor impurity in a substance.
2. Extraneous material added to a sample prior to or during
chemical or biological analysis.
3. Unintended pesticide residue in an agricultural commodity
or environmental compartment (e.g. ground water). See
also pollutant.
control sample (field) Sample from a
field test plot to which no pesticide was applied (a zero rate sample) or
which received chemical treatments identical to the test plots except for
the test chemical.
critical concentration
Lowest concentration of a pesticide in an environmental compartment
at which adverse effects on organisms are likely to be observed (95%
probability).
critical load Amount of
a pesticide leading to a critical
concentration when received by an environmental compartment.
(US-EPA, 1992)
cumulative effect Overall adverse change
which occurs when repeated doses of a pesticide have biological consequences
which are additive. (after Duffus, 1993)
cut-off value Numerical value
set by regulatory authorities representing the limit of acceptability
for a property or behaviour of a compound for the final step in tiered
assessment schemes. See also trigger value.
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