Activity Concentrations of Sr-90 and Cs-137 in Seawater and Sediment in the Gulf of Tonkin, Vietnam

Table 4

Results of reference materials for QC of soil and seawater sample.

Sample	Isotope	Lab value ± uncertainty (Bq/kg)	Certified/reference value ± uncertainty (Bq/kg)	Bias (%)
IAEA-RML 2017–01; (seawater)	Sr-90	0.31 ± 0.04	0.2472 ± 0.0019	25.4
	Cs-134	0.207 ± 0.015	0.1937 ± 0.0008	6.8
	Cs-137	0.304 ± 0.022	0.3070 ± 0.0019	−1.0
IAEA-375; (Russian soil)	Sr-90	103 ± 13	108	−4.6
IAEA-447; (Moss soil)	Cs-137	422 ± 13	425 ± 10	−0.7