Rice finding 303
Source evidence and comparison details for the Rice profile.
Local rice, raw as purchased (form not specified) · Total arsenic (tAs) · Sample count unreported.
Selected finding and reference
Sample count unreported. Basis: unspecified in the sentence; samples oven-dried at 80 C before digestion and companion figures are on dry mass, so most likely dry mass.
detected value (above stated 0.05 ug/g limit)
HMI baseline position
Moderate · HMI uncooked-grain tAs reference · 16 sampling families. Individual sample as reported: 127 µg/kg. HMI median 139–140 (bounded); Q1 110; Q3 230 µg/kg. 16 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 Alrashdi et al. (2024): Moderate.
- Without WHO GEMS/Food: Moderate.
- Without Authors 2016: Moderate.
- Without Clair-Caliot et al. 2021: Moderate.
- Without EFSA 2009: Moderate.
- Without Gama et al. 2025: Moderate.
- Without Implications 2023: Moderate.
- Without Limmer et al. 2026: Moderate.
- Without Liu et al. 2022: Moderate.
- Without Lockwood et al. 2023: Moderate.
- Without A.A. et al. 2008: Moderate.
- Without Moreda-Pineiro et al. 2020: Moderate.
- Without Sim et al. 2024: Moderate.
- Without U.S. 2021: Moderate.
- Without Zavala et al. 2008: Moderate.
- Without Wheat et al. 2024: Moderate.
These checks show dependence on each sampling family; they are not confidence intervals.
Collection period
2018
No year-by-year sample register is reconstructed from this summary.
Geographic scope
Local rice originating from
Reported growing area.
Sampling, analysis and reporting limits
Oven-dried (80 C, 48 h), ground to 0.25 mm; HNO3 digestion at 80 C (Bhatti et al. 2013 protocol) in Ouagadougou; total As by ICP-MS (Agilent 7500cx) at Eawag.
detected value (above stated 0.05 ug/g limit)
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 |
|---|---|---|
| sample_value | Local rice originating from Burkina Faso had an initial As content of 0.127 µg/g | ug/g x 1000 |
Results, 'Cooking of As-Contaminated Vegetables and Market Food Products', p.7.
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 uncooked-grain tAs reference · 16 sampling families. Uncooked grain as analysed (native or unstated moisture), µg/kg. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 110 | 139–140 (bounded) | 230 |
| Alternative weighting | 110 | 139–140 (bounded) | 230 |
102 reference units; 16 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Alrashdi et al. (2024) | 6 | 6% |
| WHO GEMS/Food | 49 | 6% |
| Authors 2016 | 3 | 6% |
| Clair-Caliot et al. 2021 | 1 | 6% |
| EFSA 2009 | 2 | 6% |
| Gama et al. 2025 | 1 | 6% |
| Implications 2023 | 11 | 6% |
| Limmer et al. 2026 | 1 | 6% |
| Liu et al. 2022 | 2 | 6% |
| Lockwood et al. 2023 | 11 | 6% |
| A.A. et al. 2008 | 5 | 6% |
| Moreda-Pineiro et al. 2020 | 3 | 6% |
| Sim et al. 2024 | 1 | 6% |
| U.S. 2021 | 2 | 6% |
| Zavala et al. 2008 | 3 | 6% |
| Wheat et al. 2024 | 1 | 6% |
Methods
HMI calculates a pooled distribution of subgroup medians across the admitted sampling families. 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
- Alrashdi et al. (2024)
- WHO GEMS/Food
- Authors 2016
- Clair-Caliot et al. 2021
- EFSA 2009
- Gama et al. 2025
- Implications 2023
- Limmer et al. 2026
- Liu et al. 2022
- Lockwood et al. 2023
- A.A. et al. 2008
- Moreda-Pineiro et al. 2020
- Sim et al. 2024
- U.S. 2021
- Zavala et al. 2008
- Wheat et al. 2024
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-native-tAs:1784506f9277
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.