Sample a Found b mg g−1 I II III IV ETAAS I 0.155 ± 0.003 0.153 ± 0.002 0.157 ± 0.004 0.159 ± 0.005 0.16 ± 0.004 II 0.212  ± 0.004 0.210 ± 0.005 0.215 ± 0.002 0.220 ± 0.003 0.21 ± 0.006 III 0.114 ± 0.002 0.109 ± 0.003 0.117 ± 0.005 0.110 ± 0.004 0.12 ± 0.005 IV 0.445 ± 0.003 0.450 ± 0.004 0.447 ± 0.003 0.444 ± 0.005 0.45 ± 0.007 a The samples, which were taken from persons who were seriously suffering from lead poisoning, were provided by Benha University Hospital. b Results expressed as: is the mean of n observations of x, s is the standard deviation, t is a distribution value chosen for the desired confidence level.

Table 6: Determination of Pb2+ in clinical samples