Method Validation. The proposed method was validated
by comparison with the ETA-AAS technique, and lead was
determined in mineralized samples using a microwave digestion
bomb. A volume of 2.0 mL of samples (wine, beer, cider,
and other alcoholic beverages) was treated with 2.5 mL of 65%
(v/v) HNO3 and a few micrograms of V2O5 at the maximum
setting for 90 s and brought to a final volume of 25 mL with
deionized water. Lead was determined in the resulting
solutions by ETA-AAS. An aliquot of 10 íL was injected into
a graphite tube and run under optimized conditions (Cabrera
et al., 1994b, 1995). CAUTION: Start with small samples,
small amounts of acid, and short digestion times and then
increase only if necessary. Cooling the digestion bomb as
described in the operating instructions is a particularly
important safety consideration. It is also recommended that
the bomb should remain in the microwave oven after the