Table 3 Measured and certified values of the metals in SRM 2709a and SRM 1640a.

From: Toxic and heavy metals contamination assessment in soil and water to evaluate human health risk

Metal

Certified value SRM 2709a (µg g−1)

Measured value \(\left( {\overline{x} \pm ts/\surd n} \right)\)

Certified value SRM 1640a (µg kg−1)

Measured value \(\left( {\overline{x} \pm ts/\surd n} \right)\)

% Recovery SRM 2709a/SRM 1640a

Toxic metals

 

Cr

130 ± 9

132.9 ± 2.7

40.22 ± 0.28

39.20 ± 1.52

102.2/97.5

Mn

529 ± 18

527.9 ± 1.8

40.07 ± 0.35

39.13 ± 1.32

99.8/97.6

Cu

33.9 ± 0.5

33.5 ± 0.67

85.07 ± 0.48

85.34 ± 0.58

98.8/100.3

As

10.5 ± 0.3

11.3 ± 0.52

8.010 ± 0.067

8.00 ± 0.59

107.6/99.8

Heavy metals

 

Cd

0.371 ± 0.002

0.362 ± 0.04

3.961 ± 0.072

3.690 ± 0.279

97.6/93.2

Ba

979 ± 28

973.3 ± 7.8

150.60 ± 0.074

151.88 ± 1.224

99.4/100.8

Hg

0.09 ± 0.02

0.09 ± 0.004

100/–

Pb

17.3 ± 0.10

17.8 ± 0.29

12.005 ± 0.040

11.887 ± 0.389

102.9/99.0

  1. (\(\overline{x} \pm ts/\surd n\)) = mean ± CI (p < 0.05, n = 6), CI = Confidence interval.