Groundwaters from flows and wells in Springwater Township, Ontario, were measured for antimony and scandium by sector-field ICP-MS using clean-lab methods developed for polar ice. The groundwater antimony maximum was 5.0 ng/L and the mean of all groundwater samples was 2.2 ± 1.2 ng/L (n=34); scandium averaged 8.6 ± 4.7 ng/L (n=28). A swamp and a creek sampled for comparison were higher in antimony (12.4 and 23.4 ng/L). The first water from a brass faucet contained 16.3 ng/L antimony and was treated by the authors as tap or solder contamination; later samples from that source were at or below 2.0 ng/L. The paper also measured antimony in laboratory plastics and in hydrochloric acid passed through a plastic dispenser, as contamination checks rather than as groundwater concentrations.
Key numbers
| Analyte | Matrix | Value | Unit | Statistic | N | Where |
|---|---|---|---|---|---|---|
| Sb | Springwater Township groundwater | 2.2 ± 1.2 | ng/L | mean | 34 | PDF p.1 |
| Sb | Springwater Township groundwater | 5.0 | ng/L | max | 34 | PDF p.1 |
| Sb | Springwater Township groundwater | 0.9 | ng/L | min | PDF p.5 (printed 1241) | |
| Sc | Springwater Township groundwater | 8.6 ± 4.7 | ng/L | mean | 28 | PDF p.1 |
| Sb | swamp surface water, comparison sample | 12.4 | ng/L | single | 1 | Table 1, PDF p.4 (printed 1241) |
| Sb | creek surface water, comparison sample | 23.4 | ng/L | single | 1 | Table 1, PDF p.4 (printed 1241) |
| Sb | first draw from a brass faucet | 16.3 | ng/L | single | 1 | PDF p.3 (printed 1239) |
| Sb | ICP-SMS method | 30 | pg/L | lod | PDF p.1 | |
| Sc | ICP-SMS method | 5 | pg/L | lod | PDF p.1 |
Methods (brief)
Samples collected in acid-cleaned 100 mL LDPE with 100 μL in-house sub-boiled HNO3 already added. Unfiltered. ICP-SMS with APEX Q and low-flow PFA nebulizer. SLRS-4 measured Sb 245 ± 9 ng/L versus certified 230 ± 40 ng/L; Sc 10.1 ± 0.6 ng/L versus reference 11.3 ± 0.6 ng/L.
Detection and reporting: Sb LOD 30 pg/L; Sc LOD 5 pg/L. Mean blank (0.5% HNO3, n=15) 43 ± 10 pg/L Sb. INAA LOD for plastic 0.1 mg/g Sb.
Basis: Dissolved/acidified unfiltered water, ng/L. Not a dry-weight solid. Not a migration test. Speciation of Sb was not determined.
Evidence fitness
This source can support: Natural-abundance total Sb and Sc in these Ontario groundwaters; Method LOD at pg/L; Evidence that some laboratory plastics and dispensers can contaminate Sb blanks.
It cannot support: Bottled-water occurrence (other studies are cited, not measured here); Sb speciation; A drinking-water compliance dataset for a product; Landfill leachate concentrations (cited from Looser et al., not measured here).
Limitations
Table 1 publishes site means, not every replicate. Those site means stay in the evidence ledger. The public table above keeps the study-level groundwater summary, the two surface-water comparison samples, and the first-draw faucet result the authors treated as tap or solder contamination. Surface-water antimony (12.4 and 23.4 ng/L) is higher than the stated groundwater maximum of 5.0 ng/L. The two matrices are not pooled. A comparison paragraph cites other bottled-water studies and prints a World Health Organization maximum allowable concentration of 5 µg/L beside a cited median of 2 µg/L (range 1 to 50 µg/L). The text layer of that paragraph drops the micro prefix and prints mg/L. Those figures are citations, not measurements from this groundwater study, and they are not used as an antimony limit from this source. Sb oxidation state was not measured. Household and farm names in Table 1 are sampling locations.
Related evidence
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