A liquid extraction method is described that permits rapid determination of
cholecalciferol (D-3) in rodenticidal grain baits. Purified D3 was incubat
ed for various time periods to produce pre-D-3. Response ratios (concentrat
ion/detector response) for various concentrations of pre-Da and Dg in solut
ions permitted generation of a correction factor for direct quantitation of
pre-D-3 in solutions with a pure Dg standard. The method has equal precisi
on and accuracy, yet is simpler and less time consuming and requires less s
olvents than widely accepted methods for extracting DQ from grain baits. Re
coveries from control oat baits fortified at 0.05 and 0.75 wt % were 100.9
and 98%, respectively. A standard curve for concentrations ranging from 6.4
to 204 mu g/mL had an r(2) of 0.9999 and an intercept of zero and was line
ar and proportional. The (-4) wt % D-3.