[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]
quantitative structure-activity relationship
(QSAR) Quantitative association between the physio-chemical properties
of a pesticide or the properties of its molecular substructures and its biological
properties including its non-target toxicity.
random sample Sub-set of a sampling population
that is arrived at by selecting units such that each possible unit has a fixed
and determinate probability of selection.
raw agricultural commodity
Part of a crop used as a food or feed commodity directly from the harvested
crop without processing.
raw data All original laboratory records
and documentation, or verified copies thereof, including data directly
entered in a computer. They are the results from the original activities
and observations in a GLP study.
recovery, analytical Fraction or percentage
of a pesticide residue recoverable following extraction and analysis of a
matrix containing the pesticide. (after Gold et al, 1987)
redox potential Electrical potential indicating
the relative activity of oxidised and reduced species. The redox potential
of an environmental matrix is a measure of the extent to which oxidising
species are present to act as terminal electron acceptors in respiration.
re-entry interval Minimum time between
pesticide application and human re-entry to a treated area. Established by
a regulatory authority to assure safety of workers from exposure to residues.
reference dose Expected
dose resulting from human exposure to a pesticide at the level at which
it is regulated in the environment. (US-EPA, 1992). See also acceptable
daily intake, tolerable daily
intake.
reference material Material
or substance containing pesticide of interest at levels sufficiently
homogenous and well characterised to be used for the calibration of
an apparatus or assessment of analytical method performance. (after
Thompson and Wood, 1995). See also certified
reference material.
registration The process whereby the
responsible national government authority approves the sale and use of a pesticide
following the evaluation of scientific data demonstrating that the pesticide
is effective for the purposes intended and not unduly hazardous to human or
animal health or the environment. (FAO, 1986)
regulatory method Validated analytical
method which can be applied using commonly available laboratory equipment
and instrumentation. A regulatory method has the precision, specificity, limit
of determination, etc, needed to test compliance with the regulations.
repeatability For an analytical method,
the closeness of agreement between results of measurements on identical test
material subject to the following conditions: same analyst, same instrumentation,
same location, same conditions of use, repetition over a short period of time.
(after Metrology, 1984)
reproducibility For an analytical method,
the closeness of agreement between results of measurements on identical test
material where individual measurements are carried under changing conditions
such as: analyst, instrumentation, location, conditions of use, time. (after
Metrology, 1984)
resistance Development of tolerance
to a pesticide by a target population, generally through natural selection.
respiration Energy-generating process
in an organism where an organic or inorganic compound serves as the electron
donor and an inorganic compound (e.g. oxygen) serves as the electron acceptor.
retention sample Sample which is stored
for a specified period in case of a need for re-evaluation of data obtained
from the main laboratory samples.
risk Probability of any defined hazard
occurring from exposure to a pesticide under specific conditions. Risk
is a function of the likelihood of exposure and the likelihood to harm
biological or other systems. See also hazard.
risk assessment Process of
defining the risk associated with a specified use pattern for
a pesticide, usually expressed as a numerical probability or as a margin
of safety. Quantifying risk ideally requires,
- identification of hazard,
- establishment of dose-response relationships
in likely target individuals and populations,
- exposure assessment (using
likely exposure patterns as opposed to worst-case estimates).
(after Duffus, 1993)
risk management Decision-making
process and procedures used by regulators and others to limit potential
risks from use of pesticides. This involves risk
assessment, emission control, exposure
control and evaluation of the success of the risk mitigation efforts.
rotational crop Crop grown
in sequence of two or more different crops.
run-off
- Movement of a pesticide from a treated field by surface water and
eroding sediment.
- Loss of formulation off foliage during spray application, particularly
at high volume.
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