Elements

Certified values

MWD

Mean ± SD

(%) Recovery

Paired t-testa

tExperimental

Certified sample of whole blood (μg/l)

Ca (mg/l)

14.7 ± 0.3

14.65 ± 1.2

(8.19)

99.7

0.985

Pb (μg/l)

105 ± 24

104.8 ± 7.3

(6.96)

96.8

0.0012

Certified sample of human hair (μg/g)

Ca

1560 ± 40c

1556.5 ± 55.2

(3.54)

99.8

0.883

Pb

33.0 ± 1.2

32.56 ± 1.18

(3.62)

98.7

0.095