Rice finding 1826
Source evidence and comparison details for the Rice profile.
White medium grain (U.S. mill composite), cooked whole-grain composite · Inorganic arsenic (iAs) · Sample count unreported.
Selected finding and reference
Sample count unreported. Basis: dry weight of cooked composite (50-g rice composites cooked in 18-MOhm water with no residual water, then oven dried and ground before DNAS extraction).
All rice composites contained quantifiable iAs (Conclusions); DNAS iAs MDL 0.09 ng/g
HMI baseline position
High · HMI cooked-rice iAs reference · 3 sampling families. Mean as reported: 77 µg/kg. HMI median 28.5; Q1 28; Q3 41.6 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 is an external comparison; the finding does not set the reference.
Sensitivity to weighting
Equal subgroup weight within each family: High. The position is unchanged under this alternative. This check does not address all sampling, rounding or analytical uncertainty.
Sensitivity to source selection
- Without FDA Total Diet Study, FY2018–FY2020: High.
- Without WHO GEMS/Food: Limited data.
- Without Baxter et al. 2015: High.
These checks show dependence on each sampling family; they are not confidence intervals.
Collection period
2009
No year-by-year sample register is reconstructed from this summary.
Geographic scope
White Medium Grain
Rice variety or type within one study.
Sampling, analysis and reporting limits
Microwave total digestion with ICP-MS (total As); dilute nitric acid extraction and speciation (DNAS) and in vitro gastrointestinal extraction, both with IC-ICP-MS (Hamilton PRP-X100, Agilent 7700); iAs = AsIII + AsV.
All rice composites contained quantifiable iAs (Conclusions); DNAS iAs MDL 0.09 ng/g
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 | DNAS (ng/g ± 2σ) 77.0 ± 18.3 | none (ng/g = ug/kg) |
Figure 3B legend (DNAS column), p.057005-6.
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 cooked-rice iAs reference · 3 sampling families. Cooked rice as prepared, µg/kg as eaten. Distribution of sample or subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 28 | 28.5 | 41.6 |
| Alternative weighting | 28 | 28.5 | 41.6 |
15 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| FDA Total Diet Study, FY2018–FY2020 | 1 | 33% |
| WHO GEMS/Food | 13 | 33% |
| Baxter et al. 2015 | 1 | 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, FDA Total Diet Study cooked composites 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-cooked-iAs:6d709469f065
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.