SPSFAM Heavy Metals ERP Book

K ubachka et al .: J ournal of AOAC I nternational V ol . 100, N o . 4, 2017  1079

Table 1. Summary of mean concentration, repeatability, and reproducibility data for analysis of RTD apple, grape, and pear juice and apple juice concentrate samples Analyte Matrix No. of Labs No. of replicates Analyte added, µg/kg Mean concn, µg/kg s r s R RSD r , % RSD R , % HorRat

8 8 8 8 8 8 8 8 8 8 8 8 8 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7

11.5 24.8 5.63 5.96 14.4 12.4 23.2 5.92 14.7 5.85 27.2

AJ1 AJ2 AJ3 GJ1 GJ2 GJ3 GJ4 PJ1 PJ2 PJ3 AJ1 AJ2 AJ3 GJ1 GJ2 GJ3 GJ4 PJ1 PJ2 PJ3 AJ1 AJ2 AJ3 GJ1 GJ2 GJ3 GJ4 PJ1 PJ2 PJ3

24 24 24 24 23 24 24 24 24 24 24 24 24 21 21 21 21 20 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21 21

0.34 0.81 3.0

7.0 0.22

25 As(V)

0.96 2.66 3.9 10.7 0.38 0.24 0.59 4.3 10.5 0.30

0.25 0.67 4.2 0.31 0.57 2.1 0.45 0.60 3.6 0.80 1.63 3.4 0.26 0.68 4.4 0.48 0.97 3.2

11.3 0.33 3.9 0.13 4.9 0.16 7.0 0.25 11.5 0.33 6.6 0.22

iAs a

10 As(V)

10 As(III)

0.26 0.70 4.5 12.0 0.35

AJC1 AJC2 AJC3

1.40 2.61 5.2

9.6 0.35

TR (9.94) b TR (4.94)

0.43 2.71 4.4 27.2 0.85 0.90 3.26 18.2 66.0 1.86

NA c

<0.25 <0.25 <0.25

NA NA NA NA

NA NA NA NA NA NA NA NA NA NA 0.20 0.31 21.8 33.3 0.73 0.11 0.31 9.8 27.7 0.62 0.08 0.25 10.9 31.7 0.68 0.11 0.25 12.0 27.5 0.60 0.26 0.55 54.2 115.6 2.3 NA NA NA NA NA 0.45 2.18 10.4 50.2 1.39 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.05 0.46 6.5 58.2 1.24 NA NA NA NA NA NA NA NA NA NA NA NA NA NA NA 0.95 1.9 3.3 6.7 0.24 0.71 2.09 3.1 9.3 0.33

TR (0.94)

28.8

30 DMA

TR (1.12) TR (0.78) TR (0.93) TR (0.48)

DMA

<0.25

TR (4.34)

AJC1 AJC2 AJC3

<1.5 <1.5

<0.25

22.5

25 MMA

TR (0.79)

<0.25 <0.25 <0.25

MMA

9.11 27.0

10 MMA 30 MMA

0.32 0.69 3.5 0.61 1.95 2.2

7.6 0.23 7.2 0.26

<0.25 <0.25 55.5 < 1.5 < 1.5

NA NA NA NA NA NA NA NA NA NA

AJC1 AJC2 AJC3

2.42 3.33 4.4

6.0 0.24

NA NA NA NA NA NA NA NA NA NA

a  Measured as As(III) + As(V). b  TR = Trace; a result >LOD but ≤LOQ is reported as TR, with the value in parentheses. c  NA = Not applicable.

(a)  Fortified analytical portions (FAPs) for RTD samples .— For this validation, duplicates of three levels were prepared for samples AJ1, PJ1, and GJ1 by the following method: Prepare an analytical portion fortified withAs(III), DMA, MMA, andAs(V) at levels of 5, 25, and 50 μg/kg each by combining 2 g RTD juice and appropriate amounts of the 1000 ng/g multianalyte

spiking solution (or a diluted version of this solution) in a 15 mL polypropylene centrifuge tube. Dilute to 10 g total with deionized water (DIW) and mix thoroughly (the spiking levels are 1, 5, and 10 ng/g each in this solution, respectively). Draw an approximately 4 mL aliquot of the analytical solution into a syringe and dispense through a 0.45 μm nylon or PTFE syringe