injection chemical vapor generation ICP-MS [11]. The use of gold trap
was well exploited for mercury pre-concentration and speciation in a
variety of environmental samples [12].
The lack of certified reference gasoline samples makes difficult the
validation of the analysis accuracy. Ways to circumvent this problem
are, for example, to carry out analysis by different techniques or by
applying recovery tests. Other problems in relation to trace analysis of
petroleum products are: (i) calibration using the standard addition
technique may lead to errors, since the analyte forms in the material
to be analyzed are unknown and may behave differently in comparison
to the spiked form; (ii) the potential loss of the analyte during
sample preparation and (iii) the low levels of the analytes present
in this kind of sample, as already mentioned [7,13]. The last point is
of special concern, since the size of the production, refining and consumption
of petroleum products may result in a relatively large emission
of contaminants to the environment [14,15].
The aim of this work is to investigate and develop a new method
for the determination of total mercury in gasoline by CV-GF AAS after
a simple sample dilution in ethanol, mercury reduction directly from
the organic medium and calibration with aqueous standard solutions.
In order to attain the required detection limit, pre-concentration steps
will be included in the procedure, after the cold vapor generation.
According to our knowledge, the strategies adopted in this work were
not used before for the determination of Hg in gasoline.