Arsenic is the best-measured metal in rice protein, from FDA retail sampling of powders and rice-labeled protein drinks.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → Total arsenic in that survey ran from 82 to 230 µg/kg, and inorganic arsenic had a median of 45.5 µg/kg across 16 units.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →
-
Metals of concern:
Inorganic arsenic, lead and cadmium are the central concerns, and each source measured only some of the metals.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source →2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source → One rice protein concentrate held 175 µg/kg lead, with cadmium not detected.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source → Rice endosperm protein made in Japan averaged 140 µg/kg cadmium across five batches.5A Randomized, Double-Blind, Crossover Pilot Trial of Rice Endosperm Protein Supplementation in Maintenance Hemodialysis PatientsScientific ReportsRead source →
-
Main drivers:
Product form and arsenic speciation change how results compare, and inorganic arsenic cells derived from total arsenic are held.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → The surveys name purchase markets, not growing areas, so origin cannot be ranked.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source →
-
Practical framing:
The EU cadmium maximum of 1,000 µg/kg for food supplements applies only when the product is sold as a supplement.4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → Ask for inorganic arsenic, total arsenic, lead, cadmium and mercury on the same lot.
Rice protein overview
Rice protein in the HMI library has 47 reported results for lead, cadmium, total arsenic, inorganic arsenic, total mercury, nickel and chromium from 3 sources.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source →2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source → The FDA summary table for dietary supplements lists 12 rice protein powders with average inorganic arsenic of 1.9 µg per serving and a range of 0.1 to 5.7 µg per serving. 2 That serving figure is not a concentration: the full analytical results give total arsenic and inorganic arsenic in µg/kg of the product as analyzed. One powder in that full table, sample 333512053, described as brown rice protein powder, is 260 µg/kg total arsenic and 99 µg/kg inorganic arsenic. 2 Another, sample 333688312, described as an organic meal replacement in the rice protein powder subcategory, is 120 µg/kg total arsenic and 67 µg/kg inorganic arsenic, with 5.7 µg inorganic arsenic printed for an 85 g serving. 2 The Canadian survey reports one brown rice protein powder at 0.022 ppm total mercury, which is 22 µg/kg, and does not give lead, cadmium, or arsenic for that sample. 3 The Lopez mineral table reports rice concentrate product 2 at 175.40 µg/kg lead, with a standard deviation of 3.15, and both rice concentrates not detected for cadmium. 1
Lopez-Calabozo and colleagues reported lead at 175 µg/kg (mean ± 3.15 SD) in rice protein, as sold from Rice protein concentrate, anonymized product 2.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source → That 175 µg/kg is the engine rounding of the printed mean 175.40 µg/kg, whose standard deviation is 3.15. 1 The other rice concentrate in the same table was not detected for lead. Both were not detected for cadmium. The sentence is one lot, not a typical value for every rice protein. It is kept beside the FDA arsenic results because lead and arsenic were measured by different studies.
For a buyer the practical points are the form bought, the basis a result is reported on, where the rice protein came from and the laboratory’s reporting limit. The EU sets a maximum of 1,000 µg/kg cadmium for food supplements (as placed on the market; this is the supplement row, not a rice-protein row).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → Testing finds contamination but does not remove it. The FDA rows are United States retail products from the sampling released in 2013, including the earlier sampling from the previous year, and they do not name a growing state for these powders. Where dimethylarsinic acid and monomethylarsonic acid are marked not speciated, the inorganic arsenic cell is an assumption from the total-arsenic result and is held out of the reference. 2 The detection limit for total arsenic in the dietary-supplement and protein-beverage group is 10 µg/kg, and the inorganic arsenic detection limit for that group is 2 µg/kg. 2 A 30 g scoop of the Lopez rice concentrate at 175.40 µg/kg lead is 5.262 µg of lead, far above the 0.5 µg/day California reproductive-toxicity level if that scoop is the whole day. 15 That arithmetic is a scoop check, not a dietary survey, and the European Union milled-rice inorganic arsenic row is a grain limit, not a rice-protein limit.
What counts as rice protein
This page covers rice protein in 2 forms kept separate in every comparison: rice protein, as sold (44 results) and rice protein, powder or ground (3 results).1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source →2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source → arsenic (As) sold covers the FDA powders and the rice-labeled protein beverage products, whose concentrations are of the product as analyzed. Powder or ground on the unstated basis is the Lopez rice concentrates and the single Canadian mercury sample is kept with its own note. Seven FDA beverage rows are included only where the printed description says rice protein or brown rice protein, not every high-protein drink in that subcategory. Whole rice, rice flour, and rice drinks that are not protein products stay on the rice pages. A rice endosperm protein trial is named in the deposit notes and is not used, because its table is not in this unit.
Results stay on the basis each source reports: as sold or fresh weight, dry weight, or unstated. Dry-weight, as-sold and unstated results are never pooled, and no moisture conversion is applied. FDA concentrations are µg/kg of the product, and the per-serving column is a separate calculation using the serving mass or the mass used to make 240 mL. Lopez does not state dry weight or as sold for the mineral means. The Canadian mercury result is 0.022 ppm in the powder, converted here as 22 µg/kg, and it is one sample. Trace values in the FDA table sit between the detection limit and the quantification limit, and the parenthetical figure is not treated as a fully quantified result. Non-detects stay intervals up to the limit and are not entered as zero.
Heavy metal contamination profile of rice protein
The table holds every extracted rice protein result: one row for each statistic a source reports for a form, group and metal, 47 rows in all, grouped by metal and form; percentiles, ranges and maxima for the same samples as a mean or median are shown on that row.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source →2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source → Monitoring medians are HMI calculations from individual submissions; non-detects remain intervals between zero and the reporting limit and are never read as zero. Twelve powders and seven rice-labeled beverage products carry total arsenic and inorganic arsenic from the FDA full results. Lead and cadmium on this page come from the two Lopez rice concentrates, not from the FDA sampling, which did not measure those metals. Total mercury is the single Canadian brown rice protein powder. Nickel and total chromium are the Lopez duplicate means. Held rows are the trace totals and the inorganic arsenic cells that were not independently speciated.
31 rows can be rated against an HMI reference for the same form and basis, 0 rows have a direct same-study comparison, and the rest stay unrated with the reason recorded. 5 values from 1 source failed a check against their own source and are shown but not compared.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → A rating needs four compatible units on the same form and basis. The FDA total-arsenic and inorganic-arsenic rows are the only family large enough for that display, and only where the value is quantified rather than a trace or an unspeciated assumption. Two Lopez lead results, one of them a non-detect, cannot rate lead. One mercury sample cannot rate mercury. Unrated rows remain visible with the reason in the drawer.
Comparison methods and scope
Each row is one statistic a source reports for one form of rice protein, group and metal; percentiles, ranges and maxima reported for the same samples as a mean or median are shown on that row. Different forms and preparation states are kept apart, and dry-weight results never share a reference with as-sold or fresh-weight results. Ratings place a result against an HMI reference built from monitoring results and ordinary-setting medians for the same form and basis. Same-study contrasts compare a contaminated or treated site with its control, targeted with random sampling, a prepared form with the unprocessed one, or one group of a study with the median of its other groups. Held rows failed a check against their own source and are shown but not compared.
First displayed analyte: Lead: 2 findings from 1 source. Each row retains its statistic and measurement basis.
Filter findings
47 of 47 findings · 7 analytes
About this table
| Food form | Collection scope | Finding (µg/kg) | Comparison | Evidence |
|---|---|---|---|---|
2 findings · 1 study | ||||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 1Collection date unreportedBasis not stated | not detected. | ||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 2Collection date unreportedBasis not stated | mean. | ||
2 findings · 1 study | ||||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 1Collection date unreportedBasis not stated | not detected. | ||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 2Collection date unreportedBasis not stated | not detected. | ||
18 findings · 1 study | ||||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335118802012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335118922012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335119372012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336879312012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336879712012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336883122012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3338636092012 to 2013 | not detected. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340938712012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340939562012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340940672012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340944852012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3346209562012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | not detected. | ||
1 finding · 1 study | ||||
| Rice protein, powder or groundU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
18 findings · 1 study | ||||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335118802012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335118922012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3335119372012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336879312012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336879712012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3336883122012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3338636092012 to 2013 | not detected. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340938712012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340939562012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340940672012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3340944852012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Dietary supplement, rice protein powders, sample 3346209562012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
| Rice protein, as soldU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | not detected. | ||
1 finding · 1 study | ||||
| Rice protein, powder or groundU.S. Food and Drug Administration | Protein beverage product labeled rice or brown rice protein2012 to 2013 | sample value. | ||
1 finding · 1 study | ||||
| Rice protein, powder or groundCanadian Food Inspection Agency | Single brown rice protein powder in the 2018 to 2019 survey2018 to 2019 | sample value. | ||
2 findings · 1 study | ||||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 1Collection date unreportedBasis not stated | mean. | ||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 2Collection date unreportedBasis not stated | mean. | ||
2 findings · 1 study | ||||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 1Collection date unreportedBasis not stated | mean. | ||
| Rice protein, as soldLopez-Calabozo and colleagues | Rice protein concentrate, anonymized product 2Collection date unreportedBasis not stated | mean. | ||
Shared dataset methods and interpretation
Source summaries retain their original statistic, material, basis and censoring. Each source drawer identifies methods and overlapping samples. No matched reference or pooled distribution is inferred.
HMI rice protein tAs reference · Rice protein, as sold
Reference and scope
HMI rice protein tAs reference · Rice protein, as sold. Rice protein, as sold; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 86 | 100 | 120 |
| Alternative weighting | 86 | 100 | 120 |
15 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| U.S. Food and Drug Administration | 15 | 100% |
Methods
HMI pools subgroup medians for rice protein, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings are kept out of this reference.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
U.S. Food and Drug Administration is the only compatible sampling family for rice protein, as sold on this basis in the completed rice protein ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-11-03. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-protein-203badecdc99:9107b251b36e
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.
HMI rice protein tAs reference · Rice protein, powder or ground
Reference and scope
HMI rice protein tAs reference · Rice protein, powder or ground. Rice protein, powder or ground; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 260 | 260 | 260 |
| Alternative weighting | 260 | 260 | 260 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| U.S. Food and Drug Administration | 1 | 100% |
Methods
HMI pools subgroup medians for rice protein, powder or ground on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings are kept out of this reference.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
U.S. Food and Drug Administration is the only compatible sampling family for rice protein, powder or ground on this basis in the completed rice protein ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-11-03. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-protein-8db3b75ddfe7:9cba856802fb
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.
HMI rice protein iAs reference · Rice protein, as sold
Reference and scope
HMI rice protein iAs reference · Rice protein, as sold. Rice protein, as sold; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 38 | 45.5 | 69 |
| Alternative weighting | 38 | 45.5 | 69 |
16 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| U.S. Food and Drug Administration | 16 | 100% |
Methods
HMI pools subgroup medians for rice protein, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings are kept out of this reference.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
U.S. Food and Drug Administration is the only compatible sampling family for rice protein, as sold on this basis in the completed rice protein ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-11-03. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-protein-e572877ed71a:69ec811f795b
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.
HMI rice protein iAs reference · Rice protein, powder or ground
Reference and scope
HMI rice protein iAs reference · Rice protein, powder or ground. Rice protein, powder or ground; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 99 | 99 | 99 |
| Alternative weighting | 99 | 99 | 99 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| U.S. Food and Drug Administration | 1 | 100% |
Methods
HMI pools subgroup medians for rice protein, powder or ground on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings are kept out of this reference.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
U.S. Food and Drug Administration is the only compatible sampling family for rice protein, powder or ground on this basis in the completed rice protein ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-11-03. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-protein-f841e7876af9:1edec0e47c24
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.
HMI rice protein tHg reference · Rice protein, powder or ground
Reference and scope
HMI rice protein tHg reference · Rice protein, powder or ground. Rice protein, powder or ground; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 22 | 22 | 22 |
| Alternative weighting | 22 | 22 | 22 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Canadian Food Inspection Agency | 1 | 100% |
Methods
HMI pools subgroup medians for rice protein, powder or ground on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings are kept out of this reference.
Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Canadian Food Inspection Agency is the only compatible sampling family for rice protein, powder or ground on this basis in the completed rice protein ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.
Admitted source families
Reference version and interpretation
Frozen evidence selection: 2026-11-03. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:rice-protein-e0c00e626210:14175b3d1421
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.
The value could not be reconciled with its own paper, so it is shown but not compared.
The HMI reference for this form has fewer than four units or no measurable spread, below the display minimum.
The result is on a basis (dry weight, or not stated) that no HMI reference for this form uses, so it cannot be placed.
No findings match these filters. Change the selection or reset to show all source findings.
How metals reach rice protein
No study in the library compared rice protein from contaminated and ordinary settings, so the routes by which metals reach it are not measured here. Rice plants take up arsenic from soil and irrigation water, and the FDA sampling measured that inheritance in finished rice protein products without recording the field. Cadmium in rice is a soil and fertilizer question in the broader literature, and this deposit does not attach a soil pH, a phosphate fertilizer, or a cultivar to any protein lot. The chapter records cited for agricultural cadmium loading do not reprint a rice-protein uptake factor, so none is used here. The Lopez lead result of 175.40 µg/kg is a finished concentrate, not a soil measurement. 1 Purchase country and growing origin are not the same thing, and these tables do not separate them. Industrial-site garden-pea fruit is a different crop and is not used as a rice pathway.
Which forms and regions measured lower
The HMI reference for total arsenic in rice protein, as sold pools 15 subgroup units from 1 sampling family, with a median of 100 µg/kg and a middle half spanning 86 (lower quartile) and 120 µg/kg (upper quartile).2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → For inorganic arsenic in rice protein, as sold, the reference median was 45.5 µg/kg, with a middle half from 38 to 69 µg/kg across 16 units.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → That reference is one sampling family, the FDA retail set, not a comparison of countries. Brown rice protein is not consistently lower or higher than the other rice protein descriptions in that table, and the page does not declare a winner from one survey. Sample 333512053, labeled brown rice protein powder, is 99 µg/kg inorganic arsenic, near the middle of the quantified inorganic results rather than an outlier by name alone. 2 The Lopez concentrates have no arsenic column, so they cannot be ranked against the FDA powders for arsenic. No lot in this unit prints a growing state or a variety of rice.
In one study, total arsenic across 13 groups of rice protein ranged from 82 µg/kg (Protein beverage product labeled rice or brown rice protein) to 230 µg/kg (Dietary supplement, rice protein powders, sample 334093956); the lowest is the lowest observed in that study, not an established sourcing preference.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → The 82 µg/kg end is sample 333512027, brown rice protein chocolate flavor, in the protein-beverage rows. 2 The 230 µg/kg end is sample 334093956, a blend of protein, fruits, and vegetables filed under rice protein powders. 2 A blend is not a pure rice protein, and the FDA subcategory is what placed it on this page. The span is one survey, not a regional ranking. Inorganic arsenic for those same rows is a separate column and is not summarized by this total-arsenic sentence.
Processing, cooking and preparation
No study in the library measured the same rice protein before and after washing, peeling, drying or cooking for metals, so no processing effect can be stated. Heat does not destroy metals; cooking or drying changes a concentration by moving water or metal, not by removing the element. Rice protein is separated from the grain by wet fractionation, the same class of aqueous extraction and isoelectric precipitation described for other plant isolates, and this page does not copy a soy precipitation pH onto rice. Arsenic that is already in the grain can follow the protein fraction or another fraction, and no table here weighs bran, endosperm, and protein from one lot. The FDA per-serving numbers already use the product as sold or as prepared, not a cooking-loss experiment. Heat does not destroy arsenic, cadmium, or lead. A claimed percent removal needs the paired masses and the basis, which these sources do not print.
Mitigation for rice protein
No control for metals in rice protein was measured in the library; lot testing against the applicable limit remains the verifiable step. Field water management, cultivar, and milling can change arsenic and cadmium in rice grain on other pages, and those trials are not repeated on these protein lots. No washing or precipitation experiment in this deposit reports a before-and-after change for rice protein. Lot testing of total arsenic and inorganic arsenic, plus lead and cadmium, is the check the tables support. A total-arsenic-only report misses the species the FDA table separates. No effect size is invented to fill the control table.
No study in this library has yet measured a way to lower heavy metals in rice protein; the results above show the levels measured, and lot testing against the applicable limit remains the verifiable check.
The rows above are retail and concentrate measurements. They show the levels in the products that were bought, not the effect of a lever. Growing practices that change rice grain are not measured through to these powders. Processing can concentrate or strip a metal only if the mass balance is published, and it is not. The practical check remains a lot result with a limit below the number you use for the scoop you sell.Trade-offs and limits of controls
Metals do not move together, so a lot that passes a lead limit says little about cadmium, arsenic or nickel unless those are tested as well. The Lopez rice concentrate with 175.40 µg/kg lead was not detected for cadmium. 1 The FDA powders carry arsenic and do not report lead. 2 The Canadian sample carries total mercury and does not report the other metals. 3 A pass on one of those sheets does not clear the metals the sheet omitted. Inorganic arsenic is not interchangeable with total arsenic when the species were not measured.
Testing rice protein for metals
Results depend on the method and its reporting limit. Reporting limits for cadmium were 0.015 µg/kg where sources stated them.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source → Reporting limits for total arsenic were 10 µg/kg where sources stated them.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → Reporting limits for inorganic arsenic ranged from 2 µg/kg (U.S. Food and Drug Administration) to 4 µg/kg (U.S. Food and Drug Administration), so a non-detect from a less sensitive method says much less.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → The FDA group that includes dietary supplements and protein beverages has a total-arsenic detection limit of 10 µg/kg and an inorganic-arsenic detection limit of 2 µg/kg. 2 Results marked trace are between detection and quantification. Results marked not speciated use an inorganic arsenic figure derived from total arsenic, and this page holds those cells. Lopez prints cadmium and lead detection limits below 0.015 and below 0.026 under the ppb heading, without restating the unit. 1 A certificate should name the basis, the species, and the quantification limit for each metal.
A useful lot result names the form, the basis and a quantification limit well below the limit that applies.4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → Ask whether the lot is rice protein, brown rice protein, or a blend, matching the FDA descriptions that were kept separate from unnamed high-protein drinks. Ask for inorganic arsenic and total arsenic, not a single arsenic column. Ask for lead, cadmium, and total mercury even though each source on this page measured only some of them. Ask for the serving mass the laboratory used if the report is per serving, because the FDA servings are not all 30 g. A non-detect without a limit cannot be compared with the 10 µg/kg FDA floor or the Lopez footnotes.
Buying and verifying rice protein
The EU sets a maximum of 1,000 µg/kg cadmium for food supplements (as placed on the market; this is the supplement row, not a rice-protein row).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → It sets 150 µg/kg inorganic arsenic for non-parboiled milled rice (a grain row, not rice protein) (rice as defined in the regulation).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → It sets 150 µg/kg cadmium for rice, quinoa, wheat bran and wheat gluten (a commodity row, not rice protein) (commodity row).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → The 150 µg/kg inorganic arsenic figure linked here is the non-parboiled milled rice row, and the 150 µg/kg cadmium figure is the rice commodity row. 4 Neither is a rice-protein maximum, and both are cited so a buyer does not apply them as if they were. The 1,000 µg/kg cadmium figure is the general food-supplement row, 1.0 mg/kg, when the product is sold as a supplement. 4 At a 30 g scoop, the California lead level of 0.5 µg/day corresponds to 16.7 µg/kg in the powder, and the Lopez product 2 result of 175.40 µg/kg is above that scoop arithmetic. 51 The cadmium dose level of 4.1 µg/day corresponds to 137 µg/kg at the same scoop, and the Lopez rice cadmium results are not detected rather than quantified against that line. 61
Exposure from rice protein
No source in the library converted rice protein concentrations into a verified estimate of intake for a defined population. Concentrations describe the food, not individual risk. FDA already prints inorganic arsenic per serving for its own serving sizes, from 0.1 to 5.7 µg for the 12 powders, and those servings are not rebased onto 30 g. Sample 333688312 is 5.7 µg inorganic arsenic at the printed 85 g serving, from 67 µg/kg in the product. 2 A separate 30 g assumption applied to the Lopez lead result is 175.40 times 0.030, or 5.262 µg lead. 1 The same 30 g assumption applied to the Canadian mercury result is 22 times 0.030, or 0.66 µg total mercury, and that survey did not print a serving. 3 None of these is an intake for a defined population. They are checks a buyer can repeat from the cited tables once the scoop mass is stated.
Evidence review and remaining gaps
Every source record that names rice protein was decided on its content: 3 occurrence extracted, 3 records in all. The occurrence table renders every extracted result; held values remain visible with their reason. The deposit unit is the rice protein pack: the FDA PDF, the Canadian survey PDF, and the Lopez table from Europe PMC. The FDA file contributes the arsenic rows for rice protein powders and for beverage products whose descriptions say rice or brown rice protein. The Canadian file contributes one mercury sample, not the means for all protein powders. Lopez contributes lead, cadmium, nickel, and total chromium for two rice concentrates. A rice endosperm protein cadmium mean is named in the deposit notes and is omitted because that table is not in the unit.
References identify the sources used in these answers. The Sources index preserves additional discovery links; inclusion there does not mean a source has been reviewed for this assessment. Corrections, completed searches, new direct evidence and changes in requirements should reopen the relevant answer. Each number in the prose is tied to the FDA full results, the FDA summary table, the Canadian mercury section, the Lopez mineral table, or a limit record. Held inorganic arsenic cells stay in the table so the assumption is visible and not used as a measured species. Growing origin is still missing. A paired grain-to-protein balance is still missing. Those gaps are why several metals stay unrated.
Rice protein FAQs
What heavy metals are found in rice protein?
The library reports lead, cadmium, total arsenic, inorganic arsenic, total mercury, nickel and chromium in rice protein, most often lead, cadmium and total arsenic.1The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesFoodsRead source →2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source →3Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportCanadian Food Inspection AgencyRead source → Total arsenic and inorganic arsenic come from the FDA retail sampling. Lead, cadmium, nickel, and total chromium come from the two Lopez concentrates. Total mercury is one Canadian brown rice protein powder. Unspeciated inorganic arsenic cells are shown and held. The list is the metals those tables actually reported.
Which origins or products of rice protein measured lowest?
In one study, total arsenic across 13 groups of rice protein ranged from 82 µg/kg (Protein beverage product labeled rice or brown rice protein) to 230 µg/kg (Dietary supplement, rice protein powders, sample 334093956); the lowest is the lowest observed in that study, not an established sourcing preference.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → The 82 µg/kg end is sample 333512027, brown rice protein chocolate flavor, in the protein-beverage rows. 2 The 230 µg/kg end is sample 334093956, a blend of protein, fruits, and vegetables filed under rice protein powders. 2 A blend is not a pure rice protein, and the FDA subcategory is what placed it on this page. The span is one survey, not a regional ranking. Inorganic arsenic for those same rows is a separate column and is not summarized by this total-arsenic sentence.
Are there legal limits for heavy metals in rice protein?
The EU sets a maximum of 1,000 µg/kg cadmium for food supplements (as placed on the market; this is the supplement row, not a rice-protein row).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → It sets 150 µg/kg inorganic arsenic for non-parboiled milled rice (a grain row, not rice protein) (rice as defined in the regulation).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → It sets 150 µg/kg cadmium for rice, quinoa, wheat bran and wheat gluten (a commodity row, not rice protein) (commodity row).4Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source → Read the supplement row as a supplement row. Read the milled-rice inorganic arsenic row as a grain row. California adds daily dose levels for lead and cadmium, which this page converts only when a scoop mass is stated. A 30 g scoop is an assumption except where a study printed its own serving. Meeting one row does not clear the metals that row does not cover.
How much of the arsenic in rice protein is inorganic?
Inorganic arsenic, the more toxic form, was measured in 19 results from 1 source, far fewer than total arsenic.2Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseU.S. Food and Drug AdministrationRead source → The summary table average of 1.9 µg per serving for 12 powders is a serving dose, not one of those concentrations. 2 Some inorganic arsenic cells are held because speciation was not run. Total arsenic can include dimethylarsinic acid, which the full table prints when it was measured. A buyer comparing only the inorganic column should read the not-speciated flag before treating the number as a species result. Nineteen results from one retail survey are not a world distribution.
What remains uncertain
Growing origin is not reported for these lots, so a country ranking is not supported. Where arsenic species were marked not speciated, the printed inorganic arsenic cell is held out of the reference. A trace result sits between the detection limit and the quantification limit. The single brown rice protein mercury result is one sample, and the survey means for all protein powders mix protein sources. A rice endosperm protein trial and a Hungarian retail survey are named in the deposit notes, but their tables are not in this unit, so their numbers are not used. No study here measured a before-and-after reduction of metals in rice protein. The FDA serving range of 0.1 to 5.7 µg is not a concentration range. Trace results and unspeciated cells are not fully quantified species measurements. One mercury sample cannot describe the category. No before-and-after processing trial is in the unit. The omitted endosperm-protein trial remains a named gap, not a silent zero.
References
Works cited on this page, in citation-number order. See Sources for this page’s source inventory. Each title links to a source record with bibliographic details, reported findings, and document provenance.
- The Influence of the Nutritional and Mineral Composition of Vegetable Protein Concentrates on Their Functional PropertiesPeer-reviewed
- Analytical Results from Inorganic Arsenic in Rice and Rice Products Sampling, the 2013 releaseRegulation
- Toxic Metals in Selected Foods to April 1, 2018 to March 31, 2019: Food chemistry to Targeted surveys to Final reportGovernment
- Commission Regulation (EU) 2023/915 of 25 April of 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Regulation
- A Randomized, Double-Blind, Crossover Pilot Trial of Rice Endosperm Protein Supplementation in Maintenance Hemodialysis PatientsPeer-reviewed
Sources
Browse Rice protein Sources for sources cited on this page and additional discovery candidates. The searchable index distinguishes verified citation use from discovery relationships whose relevance has not been established.
Update history
4 November 2026: Quick read rewritten in the canonical short format; added Hosojima 2017 cadmium in rice endosperm protein.
3 November 2026: Rebuilt from every rice protein record in the library: 3 occurrence sources, references by form and basis, same-study contrasts, verified limits.