Total and Inorganic Arsenic Contents in Some Edible Zingiberaceous Rhizomes in Thailand

Table 1

Accuracy and precision in the determination of total and inorganic arsenic in Zingiberaceae rhizomes.

Arsenic added (ng/g)	Intraday (n = 6)			Interday (n = 6)
	Found (ng/g); mean ± SD	% RSD^a	Recovery (%)	Found (ng/g); mean ± SD	% RSD^a	Recovery (%)
Total
250	244.1 ± 8.5	3.5	97.6	237.4 ± 6.7	2.8	94.9
500	473.1 ± 13.5	2.9	94.6	477.8 ± 21.2	4.4	95.6
1,000	944.7 ± 32.6	3.5	94.5	972.2 ± 48.7	5.0	97.2
2,500	2,366.3 ± 41.5	1.8	94.7	2,382.0 ± 40.6	1.7	95.3
Inorganic
50	47.3 ± 2.6	5.5	94.7	47.7 ± 2.6	5.4	95.3
100	98.1 ± 4.8	4.9	98.1	97.9 ± 3.4	3.4	97.9
500	469.8 ± 25.2	5.4	94.0	473.0 ± 21.9	4.6	94.6
1,000	943.7 ± 13.5	1.4	94.4	940.7 ± 10.7	1.1	94.1

 ^a% RSD: percent relative standard deviation.