2.2. Instrumentation
The atomic absorption spectrophotometer (Hitachi model A-1800) was used during this study. For simultaneous analysis,it consists of eight turret lamps with a wavelength range of 190–900 nm. For analysis precision, it has D2 and self reversal background correction with a grating of 1800 gooves/mm. Manufacturer brand Win 2.1 software was used for data integration and processing. The spectroscopic conditions were these; bandwidth 0.4 nm with a 1.0 filter factor and deuterium (D2) background correction. The integration time was 3.0 s set
at 5.0 mA lamp current. The analytes were detected at
213.9 nm.