Hg content was analyzed in both plants and soils. Approxi-
mately 0.5 g of plant material (dry weight basis) was subjected
to microwave-assisted digestion using an HNO3/H2O2 acid mixture
(5 + 2 mL) (Jedrzejczak, 1996). In the same manner, 0.5 g of soil
(dry weight basis) was microwave digested using 10 mL of 65%
HNO3 solution according to the EPA method 3051A (USEPA,
2007). The microwave oven used was a Milestone ETHOS TOUCH
127697series with a temperature range of 100–175 C and a pres-
sure of 1500 kPa. The total Hg was determined by cold vapor
atomic absorption spectroscopy (CV-AAS) using a Thermo Scien-
tific iCE 3000 series analyzer. Analytical quality control of the
methods was evaluated in triplicate with certified materials for
plant of tomato leaves (CRM 1753a, 34 ng g1
) and soil/sediment
(CRM008–050, 720 ng Hg g1
), and the percentage of recovery
were 98% and 97%, respectively. The detection limit was 14 ng