This Test Guideline describes procedures designed to estimate the acute oral toxicity
of substances to birds, and it provides three testing options: (1) limit dose test,
(2) LD50-slope test, and (3) LD50-only test. The LD50-slope and LD50-only options
are sequential testing procedures. The test method selected will depend on whether
or not a definitive median dose (LD50) and slope of the dose-response curve are both
needed. The limit dose test is the preferred test when toxicity is expected to be
low and lethality is unlikely at the limit dose. The limit dose should be adequate
for assessment purposes, and it is usually 2000 mg/kg-bwt. Five or ten birds are tested
at the limit dose in addition to a control group. The LD50-slope test is the preferred
test when regulatory or other requirements determine that the slope of the dose-response
curve and/or the confidence interval is required in addition to an estimate of the
LD50. This is a 3- or 4-stage test with 24 or 34 birds in addition to a control group.
The LD50-only test is the preferred test when regulatory or other requirements determine
that only the median lethal dose is required but neither the slope of the dose response
curve or the confidence interval for the LD50 is required. This may be the appropriate
test to estimate a percentile of a species sensitivity distribution of LD50s and to
provide information for product labelling purposes. This test has two stages, with
14 birds in addition to a control group.Software to be used with TG 223. Click here.
Software not part of the Mutual Acceptance of Data.