Apparatus. A Perkin-Elmer Model 1100B double-beam
atomic absorption spectrophotometer with a deuterium background
corrector (Perkin-Elmer Corp., Norwalk, CT) was used
with an 11-mA hollow cathode lamp. Hydride atomization was
done in a Perkin-Elmer quartz cell. A spectral bandwidth of
0.7 nm was selected to isolate the 217.0-nm lead line. Background
correction was not used. A flow injection analysis
system composed of a Gilson HP4 four-channel peristaltic
pump and an Omnifit six-way sample injection valve, a glass
liquid-gas phase separator, and Teflon tubes of 0.5- and 0.8-
mm internal diameter (i.d.) was used. For some types of
sample (beer and cider) we used a Moulinex Model FM-470
microwave oven on-line with a maximum potency of 600 W
and an ice bath (Cabrera et al., 1994a). Lead hydride was
generated directly from wine samples in an HNO3-H2O2
medium and was carried by argon (99.9998% purity) to the
quartz atomization cell, where it was heated by an acetyleneair
flame.