Rice finding 1583
Source evidence and comparison details for the Rice profile.
Polished white rice (uncooked, as purchased) · Lead (Pb) · Sample count unreported.
Selected finding and reference
Sample count unreported. Basis: dry weight.
All values quantified as reported; source does not state LOD/LOQ or non-detect handling.
HMI baseline position
Moderate · HMI dry-grain Pb reference · 3 sampling families. Mean as reported: 5.6 µg/kg. HMI median ≤5; Q1 ≤2.5; Q3 32 µg/kg. 3 families. Not a safety grade.
Low is below Q1; Moderate includes Q1 through Q3; High is above Q3. Reporting bounds must give the same category throughout.
This finding’s sampling family contributes to the fixed reference.
Sensitivity to weighting
Equal subgroup weight within each family: Moderate. The position is unchanged under this alternative. This check does not address all sampling, rounding or analytical uncertainty.
Sensitivity to source selection
- Without WHO GEMS/Food: Limited data.
- Without Cantoral et al. 2024: Moderate.
- Without TatahMentan et al. 2020: Limited data.
These checks show dependence on each sampling family; they are not confidence intervals.
Collection period
Collection date unreported
No year-by-year sample register is reconstructed from this summary.
Geographic scope
White Rice (US)
Reported growing area.
Sampling, analysis and reporting limits
~0.1 g powdered sample, HNO3/HCl/H2O2 hotplate wet digestion (modified Akinyele and Shokunbi), Agilent 7900 ICP-MS; total As only (no speciation).
All values quantified as reported; source does not state LOD/LOQ or non-detect handling.
Source inconsistency noted (does not affect this value): Table 1 white-rice statistics may include the 9 rinse-washed results (28 white = 9 washed + 19 unwashed per Table 2; weighted Cd check (19x13 + 9x7.0)/28 = 11.1 µg/kg matches Table 1 white Cd means 11-12), so white-rice values may understate as-sold rice.
Shared samples and study overlap
Subgroup rows, statistics of the same subgroup and the study total share samples; they are not independent results.
Each table row describes a food/analyte result. Repeated rows do not add independent samples or datasets. No cross-study trend is calculated in this comparison mode.
Reported values, conversion and source locator
| Source statistic | Original result | Displayed unit conversion |
|---|---|---|
| mean | Pb 5.6 (0.2–32) | none (µg/kg) |
Table 1 (p.4); µg/kg (Dry Weight).
No moisture, cooking-yield or species conversion is applied to the original finding above. Any basis conversion used for its HMI comparison is stated separately with the numerical target.
Open the primary publication · HMI source record
Reference and scope
HMI dry-grain Pb reference · 3 sampling families. Dry-weight grain, µg/kg dry weight. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | ≤2.5 | ≤5 | 32 |
| Alternative weighting | ≤2.5 | ≤5 | 32 |
7 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 4 | 33% |
| Cantoral et al. 2024 | 1 | 33% |
| TatahMentan et al. 2020 | 2 | 33% |
Methods
HMI pools subgroup medians from every compatible rice sampling family in the evidence ledger for this analyte, material and basis: published subgroup medians, medians HMI calculates from printed per-sample values and WHO GEMS/Food region-by-year medians (random sampling only). Each family has equal total weight; subgroups have equal weight within a family. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Dry-weight, native-moisture and cooked results are kept in separate references; no moisture conversion is assumed.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
An evidence-library reference, not a probability sample of the world rice market. Sampling families differ in frame (retail, farm, contaminated sites, monitoring) and period; GEMS/Food regions are reporting regions, not growing origins. Many submissions are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-dry-Pb:6c0ebd5619fe
The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.