Rice finding 417

Source evidence and comparison details for the Rice profile.

Liu et al. 2022

Brown rice (husked), field-collected late-season rice, sun-dried · Total arsenic (tAs) · 125 cultivars (4 plants pooled per cultivar from one paddy).

Selected finding and reference

280 µg/kg (median)Median.

125 cultivars (4 plants pooled per cultivar from one paddy). Basis: sun-dried brown rice powder; moisture basis not stated (effectively air-dried/dry weight).

No non-detects for tAs/iAs/DMA (detection rate 100%); LOD not reported.

HMI baseline position

High · HMI uncooked-grain tAs reference · 16 sampling families. Median as reported: 280 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: High. 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): High.
Without WHO GEMS/Food: High.
Without Authors 2016: High.
Without Clair-Caliot et al. 2021: High.
Without EFSA 2009: High.
Without Gama et al. 2025: High.
Without Implications 2023: High.
Without Limmer et al. 2026: High.
Without Liu et al. 2022: High.
Without Lockwood et al. 2023: High.
Without A.A. et al. 2008: High.
Without Moreda-Pineiro et al. 2020: High.
Without Sim et al. 2024: High.
Without U.S. 2021: High.
Without Zavala et al. 2008: High.
Without Wheat et al. 2024: High.

These checks show dependence on each sampling family; they are not confidence intervals.

Reference, contributing evidence and methods

Collection period

2020

No year-by-year sample register is reconstructed from this summary.

Geographic scope

Hybrid rice

Rice variety or type within one study.

Sampling, analysis and reporting limits

HNO3/H2O2 digestion, ICP-MS (Agilent 7700x) for Cd and tAs; As species by 1% HNO3 extraction and HPLC-ICP-MS (PRP-X100 anion exchange).

No non-detects for tAs/iAs/DMA (detection rate 100%); LOD not reported.

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
median	Average 0.29 ± 0.10a; Median 0.28	mg/kg x 1000

Table 1 (Descriptive statistics of Cd and As levels in brown rice of 208 cultivars); p.4.

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

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.