In vitro bioaccessibility round robin testing for arsenic and lead in standard reference materials and soil samples

• Published in: Integrated environmental assessment and management 2024-09, Vol.20 (5), p.1486-1495
• Main Authors: Dodd, Matt, Lee, Deanna, Nelson, Jasen, Verenitch, Sergei, Wilson, Ross
• Format: Article
• Language: English
• Subjects: Arsenic; Arsenic - analysis; Arsenic bioavailability; BGS119; Bioavailability; Canada; Design of experiments; Environmental assessment; Environmental Impact Assessment; Environmental management; Environmental Monitoring - methods; In vitro bioaccessibility; In vitro methods and tests; Integrated environmental assessment; Laboratories; Land use; Lead; Lead - analysis; Lead bioavailability; Reference materials; Reference Standards; Reproducibility; Smelters; Soil; Soil - chemistry; Soil analysis; Soil contamination; Soil Pollutants - analysis; Soil pollution; Soil testing; Standard reference materials; Toxicology
• ISSN: 1551-3777; 1551-3793; 1551-3793
• DOI: 10.1002/ieam.4891

In this study, we assessed the suitability of using a standard reference material (SRM) other than National Institute of Standards and Technology (NIST) 2710a or NIST 2711a in USEPA Method 1340 to determine arsenic (As) and lead (Pb) in vitro bioaccessibility (IVBA) and the capabilities of Canadian‐based laboratories to perform the method. Five laboratories participated in an initial round robin study and analyzed NIST 2710a, NIST 2711a, BGS119, and Enviromat SS‐2. Intra‐ and inter‐laboratory variability were generally acceptable with percentage relative standard deviations (RSD) of less than 20%. The mean total As and Pb concentrations obtained for BGS119 (332 and 936 mg/kg, respectively) and the mean IVBA values (As = 14.3% and Pb = 78.1%) suggested it may be a suitable and acceptable SRM, whereas the concentration of As in Enviromat SS‐2 as received (3.2 mg/kg) was deemed too low. Ten soil samples from sites with varying land use were analyzed in a follow‐up round robin study using the modified IVBA method that included BGS119 as SRM. The concentrations of As and Pb in the IVBA extracts reported by the participating laboratories were comparable. The mean As IVBA values for the field‐collected samples ranged from 0.1% to 56.4%; for Pb, they ranged from 7.0% to 121%. The lowest IVBA values were measured in mine site samples; the highest values were associated with smelter‐affected soils. The low IVBA values correlated with high iron content. Intra‐ and interlaboratory reproducibility were acceptable (RSD