Rice finding 1783

Source evidence and comparison details for the Rice profile.

Bazie et al. 2022

Rice grain unspecified (raw rice from open markets) · Nickel (Ni) · Sample count unreported.

Selected finding and reference

1,620 µg/kg (median)Median.

Sample count unreported. Basis: unspecified (samples stored dry at room temperature and ground; basis not stated).

median above LD; LD value not reported

HMI baseline position

High · HMI uncooked-grain Ni reference · 3 sampling families. Median as reported: 1620 µg/kg. HMI median 410; Q1 206; Q3 1420 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 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

2020

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

Geographic scope

Dakola

Purchase or reporting market; growing origin not identified.

Sampling, analysis and reporting limits

HNO3/HCl (3:1) digestion of 0.5 g at 150 °C for 2.5 h on a heat block, diluted to 100 mL; flame AAS (Varian 240FS), external calibration.

median above LD; LD value not reported

Source inconsistency noted (does not affect this value): Niankologo and Dakola rice rows print identical Ni (1.42–2.30) and Co (0.83–1.35) ranges, and several minima/maxima recur across cities (e.g. Zn 10.72, Fe 32.70), suggesting copied range cells.

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
medianMed 1.62 (0.52)mg/kg x 1000

Table 1 (Metallic trace elements contents in cereals, mg/kg), Rice, Dakola Med row, Ni column; p.3.

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 Ni reference · 3 sampling families. Uncooked grain as analysed (native or unstated moisture), µg/kg. Distribution of subgroup median concentration values.

Reference (µg/kg)Q1MedianQ3
Primary HMI reference2064101420
Alternative weighting2064101420

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

Contributing familyReference unitsWeight
WHO GEMS/Food133%
Bazie et al. 2022533%
Lockwood et al. 20231133%

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-Ni:460f92ced488

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.