Heavy metals in Iodized salt

Quick read

Iodized salt in the HMI library has 19 reported results for lead, cadmium, total arsenic, total mercury, nickel, chromium, uranium and Cu from 3 sources.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

Metals measured:
Lead, cadmium, total arsenic, total mercury, nickel and chromium and others, in 19 results from 3 sources.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}
Main drivers:
Form, basis and where the iodized salt was sampled; reporting limits decide how many results are non-detects.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}
Practical framing:
Ask for lot results with a quantification limit well below the limit that applies in the destination market.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

Iodized salt overview

Iodized salt in the HMI library has 19 reported results for lead, cadmium, total arsenic, total mercury, nickel, chromium, uranium and Cu from 3 sources.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →} In the US Total Diet Study, iodized salt, as sold had a median lead result below 10 µg/kg across 1 composite from 2020.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Its median cadmium result there was below 3 µg/kg.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

For a buyer the practical points are the form bought, the basis a result is reported on, where the iodized salt came from and the laboratory’s reporting limit. Testing finds contamination but does not remove it.

What counts as iodized salt

This page covers iodized salt, as sold (19 results).^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

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.

Heavy metal contamination profile of iodized salt

The table holds every extracted iodized salt result: one row for each statistic a source reports for a form, group and metal, 19 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.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead 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.

4 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.

Comparison methods and scope

Each row is one statistic a source reports for one form of iodized salt, 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.

About this table

Food formCollection scopeFindingComparisonEvidence

Iodized salt findings from monitoring programmes, total diet studies and every extracted field, market and contaminated-site study, in µg/kg with each source’s form, basis, statistic and censoring retained.
Food form	Collection scope	Finding (µg/kg)

4 findings · 3 studies
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.
Iodized salt, as soldCaridi et al. 2019	food salt sample S4, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldCaridi et al. 2019	food salt sample S5, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldSpungen et al. 2024	all samples2018–2020	not detected.

4 findings · 3 studies
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.
Iodized salt, as soldCaridi et al. 2019	food salt sample S4, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldCaridi et al. 2019	food salt sample S5, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldSpungen et al. 2024	all samples2018–2020	not detected.

3 findings · 2 studies
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.
Iodized salt, as soldCaridi et al. 2019	food salt sample S4, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldCaridi et al. 2019	food salt sample S5, origin Italy, Italian retailersCollection date unreported	sample value.

3 findings · 2 studies
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.
Iodized salt, as soldCaridi et al. 2019	food salt sample S4, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldCaridi et al. 2019	food salt sample S5, origin Italy, Italian retailersCollection date unreported	sample value.

1 finding · 1 study
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.

1 finding · 1 study
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.

1 finding · 1 study
Iodized salt, as soldFDA Total Diet Study	1 collection regions2020	median.

2 findings · 1 study
Iodized salt, as soldCaridi et al. 2019	food salt sample S4, origin Italy, Italian retailersCollection date unreported	sample value.
Iodized salt, as soldCaridi et al. 2019	food salt sample S5, origin Italy, Italian retailersCollection date unreported	sample value.

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 iodized salt Pb reference · Iodized salt, as sold

Reference and scope

HMI iodized salt Pb reference · Iodized salt, as sold. Iodized salt, 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	≤10	≤10	200
Alternative weighting	≤10	≤10	200

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

Contributing family	Reference units	Weight
FDA Total Diet Study	1	33%
Caridi et al. 2019	2	33%
Spungen et al. 2024	1	33%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

3 sampling families with different designs; none is a probability sample of world supply. 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: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-362063a46547:3b9f8ec0207c

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 iodized salt Cd reference · Iodized salt, as sold

Reference and scope

HMI iodized salt Cd reference · Iodized salt, as sold. Iodized salt, 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	≤3	≤3	10
Alternative weighting	≤3	≤3	10

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

Contributing family	Reference units	Weight
FDA Total Diet Study	1	33%
Caridi et al. 2019	2	33%
Spungen et al. 2024	1	33%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

3 sampling families with different designs; none is a probability sample of world supply. 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: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-35112800344e:fab7e0208a24

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 iodized salt tAs reference · Iodized salt, as sold

Reference and scope

HMI iodized salt tAs reference · Iodized salt, as sold. Iodized salt, 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	≤7	5–8.5 (bounded)	15
Alternative weighting	≤7	5–8.5 (bounded)	15

3 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	1	50%
Caridi et al. 2019	2	50%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. 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: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-f5023a5a974a:8a8fa60e863c

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 iodized salt tHg reference · Iodized salt, as sold

Reference and scope

HMI iodized salt tHg reference · Iodized salt, as sold. Iodized salt, 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	≤3	10–11.5 (bounded)	30
Alternative weighting	≤3	10–11.5 (bounded)	30

3 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	1	50%
Caridi et al. 2019	2	50%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. 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: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-f8e91e5e3397:0892ce09b987

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 iodized salt Ni reference · Iodized salt, as sold

Reference and scope

HMI iodized salt Ni reference · Iodized salt, as sold. Iodized salt, 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	≤100	≤100	≤100
Alternative weighting	≤100	≤100	≤100

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	1	100%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for iodized salt, as sold on this basis in the completed iodized salt 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

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-86b259f3f2fe:bf4df1fd18ff

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 iodized salt Cr reference · Iodized salt, as sold

Reference and scope

HMI iodized salt Cr reference · Iodized salt, as sold. Iodized salt, 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	≤125	≤125	≤125
Alternative weighting	≤125	≤125	≤125

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	1	100%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for iodized salt, as sold on this basis in the completed iodized salt 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

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-b12664a6e115:78803814aa4b

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 iodized salt U reference · Iodized salt, as sold

Reference and scope

HMI iodized salt U reference · Iodized salt, as sold. Iodized salt, 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	≤2.5	≤2.5	≤2.5
Alternative weighting	≤2.5	≤2.5	≤2.5

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	1	100%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for iodized salt, as sold on this basis in the completed iodized salt 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

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-21c29946bdf7:e260c2ef18ea

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 iodized salt Cu reference · Iodized salt, as sold

Reference and scope

HMI iodized salt Cu reference · Iodized salt, as sold. Iodized salt, 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	600	700	800
Alternative weighting	600	700	800

2 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
Caridi et al. 2019	2	100%

Methods

HMI pools subgroup medians for iodized salt, 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–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

Caridi et al. 2019 is the only compatible sampling family for iodized salt, as sold on this basis in the completed iodized salt 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

Caridi et al. 2019

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:iodized-salt-2a5c3605f67d:10091eb2a3f1

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.

How metals reach iodized salt

No study in the library compared iodized salt from contaminated and ordinary settings, so the routes by which metals reach it are not measured here.

Which forms and regions measured lower

The HMI reference for lead in iodized salt, as sold pools 4 subgroup units from 3 sampling families, with a median of below 10 µg/kg and a middle half spanning below 10 (lower quartile) and 200 µg/kg (upper quartile).^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →} For cadmium in iodized salt, as sold, the reference median was below 3 µg/kg, with a middle half from below 3 to 10 µg/kg across 4 units.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

Processing, cooking and preparation

No study in the library measured the same iodized salt 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.

Mitigation for iodized salt

No control for metals in iodized salt was measured in the library; lot testing against the applicable limit remains the verifiable step.

No study in this library has yet measured a way to lower heavy metals in iodized salt; the results above show the levels measured, and lot testing against the applicable limit remains the verifiable check.

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.

Testing iodized salt for metals

Results depend on the method and its reporting limit. Reporting limits for lead were 10 µg/kg where sources stated them.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Reporting limits for cadmium were 3 µg/kg where sources stated them.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

A useful lot result names the form, the basis and a quantification limit well below the limit that applies.

Buying and verifying iodized salt

No maximum level for metals in iodized salt was verified from primary text for this page; buyers should confirm the limit that applies in the destination market.

Exposure from iodized salt

No source in the library converted iodized salt concentrations into a verified estimate of intake for a defined population. Concentrations describe the food, not individual risk.

Evidence review and remaining gaps

Every source record that names iodized salt 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.

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.

Iodized salt FAQs

What heavy metals are found in iodized salt?

The library reports lead, cadmium, total arsenic, total mercury, nickel, chromium, uranium and Cu in iodized salt, most often lead, cadmium and total arsenic.^{1U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{2Caridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, Belmusto G · 2019Food Salt Characterization in Terms of Radioactivity and Metals ContaminationApplied Sciences 2019, 9, 2882Read source →}^{3Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

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.

FY2018-FY2020 TDS Elements Analytical ResultsU.S. Food and Drug Administration · FDA Total Diet Study · 2022 · www.fda.govDataset
Food Salt Characterization in Terms of Radioactivity and Metals ContaminationCaridi F, Messina M, Belvedere A, D’Agostino M, Marguccio S, Settineri L, et al. · Applied Sciences 2019, 9, 2882 · 2019 · doi.org/10.3390/app9142882Peer-reviewed
Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Spungen JH and et al. · Food Additives & Contaminants: Part A · 2024 · doi.org/10.1080/19440049.2024.2396910Peer-reviewed

Sources

Browse Iodized salt 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

22 October 2026: Rebuilt from every iodized salt record in the library: 3 occurrence sources, references by form and basis, same-study contrasts.

Graph View

1

FY2018-FY2020 TDS Elements Analytical Results

2

Food Salt Characterization in Terms of Radioactivity and Metals Contamination

3

Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020

Food and Drug Administration