Overview
Ranjbar and coauthors assessed radioactive isotopes and heavy metals in 15 commercial bottled mineral water brands sold in Arak City, Iran. The heavy-metal result is reported only as a bulk non-detect at the analytical method’s reporting floor; no per-sample concentrations, LODs, reference materials, or wavelength assignments are tabulated. The abstract names lead and chromium as the metals absent from samples; the Summary and Conclusion expands the assayed list to cadmium, mercury, tin, lead, and arsenic at “zero mg/L.” The two analyte lists do not agree, and the paper provides no table reconciling them. The page is routeable as bottled/mineral-water non-detect surveillance, not as a concentration distribution.
Key numbers
- Random sampling of n = 15 commercial mineral water brands (WFR1–WFR15) collected from supermarkets in Arak City, Iran. Factory sources span multiple Iranian provinces.
- Abstract (page 1) states that lead and chromium were “not present in the samples.”
- Summary and Conclusion (page 15) states that “Heavy elements such as Cd, Hg, Sn, Pb, and As were detected at zero mg/L.” The Conclusion’s analyte list does not match the Abstract’s analyte list (Cr appears only in the Abstract; Cd/Hg/Sn/As appear only in the Conclusion). Neither location reports LODs, per-sample values, or instrument wavelengths.
- Ra-226 specific activity: zero across all 15 samples (Table 5; abstract framed as “not detected”).
- Th-232 average specific activity: 0.311 Bq/L (range 0.000–0.748 Bq/L; Table 6).
- K-40 average specific activity: 2.104 Bq/L (range 0.000–7.460 Bq/L; Table 7).
- Cs-137 average specific activity: 0.049 Bq/L (range 0.000–0.148 Bq/L; Table 8). All four radionuclide averages are below the WHO guidance levels (Ra-226 0.5, Th-232 1.0, K-40 22.1, Cs-137 10.0 Bq/L; Table 3).
- Annual effective dose averages: 57.6 µSv/y (infants), 80.7 µSv/y (children), 168 µSv/y (adults); all below the UNSCEAR reference of 1000 µSv/y (Table 9, Summary).
- Cancer incidence coefficient averages: 316 × 10⁻⁶ (infants), 442 × 10⁻⁶ (children), 922 × 10⁻⁶ (adults) (Table 10, Summary).
- Radium equivalent activity: 0–1.08 Bq/L across samples; external and internal hazard indices Hex, Hin range 0–0.002, all ≤ 1 (Table 11). Radionuclide results are routing context only for HMI metal pages.
Methods (brief)
Heavy metals were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) on a 9100 Quant Plasma instrument (manufactured in Germany) housed at the central laboratory of Arak University. Plasma operated in the 6000–10,000 K range. Three emission lines were selected per element to mitigate chemical interference, and each analysis was conducted in triplicate. LODs, reference materials, individual element wavelengths, and per-sample concentration values are not reported in the paper, which limits the defensibility of the “zero mg/L” claim and precludes pooled-percentile inclusion. Radionuclide activities were measured by gamma-ray spectrometry on a coaxial HPGe p-type detector (model 30,195 BSIGCD, 30% relative efficiency, 4096 channels, energy resolution 1.95 keV at the Co-60 1332.520 keV line) at 3000 V, calibrated against a Cs-137 standard, processed with IsrmB SI / WINHEX / MATLAB and quantified with GammaVision32 (EG&G Ortec). Marinelli beakers (800 cc) were sealed for ~50 days to reach radon-progeny equilibrium before counting.
Implications
Certification: bottled mineral-water non-detect context for the five analytes the paper assays at zero (Pb, Cd, tHg, Sn, tAs) and a sixth (Cr) named only in the abstract; not pool-eligible because no LODs or per-sample values are reported. Courses: useful example of how the absence of a per-sample table or LODs undermines a “zero” claim, even when the underlying instrument and protocol look sound. App: supports a regional, product-specific non-detect signal for Iranian bottled mineral water; does not generalize to global bottled-water exposure estimation.
Related evidence
- Mineral water
- Bottled drinking water (purified, spring, artesian)
- Water
- Lead
- Cadmium
- Mercury
- Tin
- Arsenic
- Chromium
- Quality and risk assessment of lead and cadmium in drinking water for child development centres use in Phatthalung province, Thailand
- Risk assessment of lead and cadmium in drinking water for school use in Nakhon Si Thammarat Province, Thailand
- Scientific Opinion on the risks to public health related to the presence of chromium in food and drinking water
- Heavy Metals Burden in Drinking Water: Global Patterns, Sources, and Public Health Implications
Update history
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