Rice finding 586

Source evidence and comparison details for the Rice profile.

Li et al. 2022

Rice grain unspecified · Cadmium (Cd) · Sample count unreported.

Selected finding and reference

158 µg/kg (mean)Mean.

Sample count unreported. Basis: dry weight.

none reported

HMI baseline position

High · HMI dry-grain Cd reference · 9 sampling families. Mean as reported: 158 µg/kg. HMI median 71; Q1 4.7–9 (bounded); Q3 149 µg/kg. 9 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

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

Reference, contributing evidence and methods

Collection period

2021

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

Geographic scope

Cd category 3

All samples in the study.

Sampling, analysis and reporting limits

0.20 g dried sample, HNO3 closed PTFE digestion 150-170 °C, ICP-MS (PerkinElmer NexION 2000) per Chinese multi-element food method.

none reported

Source inconsistency noted (does not affect this value): footnote bands at Pi 0.7-1 imply 0.14-0.20 mg/kg for category 3 and 0.20-0.40 for category 4, but printed boundaries are 0.130-0.184 and 0.185-0.387; with Chinese limit 0.2, part of category 4 is below the 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 statisticOriginal resultDisplayed unit conversion
mean0.158mg/kg x 1000

Table 1, Rice rows, p.5.

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 Cd reference · 9 sampling families. Dry-weight grain, µg/kg dry weight. Distribution of subgroup median concentration values.

Reference (µg/kg)Q1MedianQ3
Primary HMI reference4.7–9 (bounded)71149
Alternative weighting4.7–9 (bounded)71149

65 reference units; 9 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing familyReference unitsWeight
Myat Soe et al. (2023)511%
Shi et al. (2020)3211%
WHO GEMS/Food111%
Huang 2023311%
Li et al. 2022511%
Qin et al. 2026511%
Signes-Pastor et al. 2016911%
TatahMentan et al. 2020311%
Xie et al. 2026211%

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-dry-Cd:59d3645f9f4f

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.