On-line sorptive preconcentration platform incorporating a readily exchangeable Oasis HLB extraction micro-cartridge for trace cadmium and lead determination by flow injection-flame atomic absorption spectrometry

For 90 s preconcentration time, enhancement factors of 155 and 180, detection limits (3s) of 0.09 μg L− 1 and 0.9 μg L− 1 and relative standard deviations (R.S.D.) of 2.9% (at 4.0 μg L− 1) and 2.6% (at 20.0 μg L− 1) were obtained for cadmium and lead, respectively, with a sample throughput of 24 h− 1. The measurement trueness of the developed method was evaluated by analyzing a certified reference material and spiked environmental water samples. The proposed method is well suited to detect the target elements at concentration levels below the maximum allowed concentrations endorsed by the European Framework Directive (2008/105/EC) in inland and coastal waters.