Rice finding 1542

Source evidence and comparison details for the Rice profile.

Mahmood et al. 2015

Rice grain unspecified (packed retail rice, milling degree not stated) · Lead (Pb) · 5 rice samples (~250 g), five per brand/type, 10 types; Section 2.1 also says 210 packed rice samples (15-20 kg) were selected from markets.

Selected finding and reference

950 µg/kg (mean ± 210 SD)Mean.

5 rice samples (~250 g), five per brand/type, 10 types; Section 2.1 also says 210 packed rice samples (15-20 kg) were selected from markets. Basis: dry weight.

no non-detects reported; LOD not reported

HMI baseline position

High · HMI dry-grain Pb reference · 3 sampling families. Mean as reported: 950 µg/kg. HMI median ≤5; Q1 ≤2.5; Q3 32 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

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

Reference, contributing evidence and methods

Collection period

2013

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

Geographic scope

Domestic Taarom

Rice variety or type within one study.

Sampling, analysis and reporting limits

AOAC 999.11 dry ashing at 450 °C after drying at 105 °C 48 h, 6M HCl, residue in 0.1 M HNO3; flame and graphite furnace AAS (Shimadzu AA-680); triplicate digestion, three readings each.

no non-detects reported; 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 statisticOriginal resultDisplayed unit conversion
mean0.95±0.21µg/g x 1000

Original SD: 0.21 µg/g dry weight.

Table 3, row Domestic Taarom, column Pb.

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 Pb reference · 3 sampling families. Dry-weight grain, µg/kg dry weight. Distribution of subgroup median concentration values.

Reference (µg/kg)Q1MedianQ3
Primary HMI reference≤2.5≤532
Alternative weighting≤2.5≤532

7 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing familyReference unitsWeight
WHO GEMS/Food433%
Cantoral et al. 2024133%
TatahMentan et al. 2020233%

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-dry-Pb:6c0ebd5619fe

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.