Rice finding 1648

Source evidence and comparison details for the Rice profile.

James et al. 2020

Rice grain, 'other' colour · Total mercury (tHg) · 1 rice samples (single result each).

Selected finding and reference

1.91 µg/kg (individual sample)Individual sample.

1 rice samples (single result each). Basis: unspecified (source does not state dry or as-sold weight).

No LOD/LOQ or non-detects reported; all 29 printed values are numeric.

HMI baseline position

Limited data · HMI uncooked-grain tHg reference · 4 sampling families. Individual sample as reported: 1.91 µg/kg. HMI median 2–2.67 (bounded); Q1 1.21–2 (bounded); Q3 1060–1080 (bounded) µg/kg. 4 families. Reporting bounds prevent a rating.

Reporting bounds or insufficient reference spread prevent a stable Low / Moderate / High classification.

This finding’s sampling family contributes to the fixed reference.

Sensitivity to weighting

Equal subgroup weight within each family: Limited data. The position remains unresolved 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

Collection date unreported

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

Geographic scope

China (B&W Rice)

Reported growing area.

Sampling, analysis and reporting limits

ICP-MS; 'quantified per ng of element / g sample'.

No LOD/LOQ or non-detects reported; all 29 printed values are numeric.

Source inconsistency noted (does not affect this value): client ID TG-20-20-11-2019 is shared by 143-28 and 143-29; 143-29 is labelled 'Peas' and may not be 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 statisticOriginal resultDisplayed unit conversion
sample_value143-28 TG-20-20-11-2019 China (B&W Rice) 1.91 otherng/g x 1

Table 1, row Sample ID 143-28; p.2.

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 tHg reference · 4 sampling families. Uncooked grain as analysed (native or unstated moisture), µg/kg. Distribution of subgroup median concentration values.

Reference (µg/kg)Q1MedianQ3
Primary HMI reference1.21–2 (bounded)2–2.67 (bounded)1060–1080 (bounded)
Alternative weighting1.21–2 (bounded)2–2.67 (bounded)1060–1080 (bounded)

36 reference units; 4 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing familyReference unitsWeight
WHO GEMS/Food2225%
Ibrahim et al. 2024125%
James et al. 2020625%
Yan et al. (2025)725%

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-native-tHg:2ef21fc64a06

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.