Watermelon

Overview

This ingredient stub was created during the FDA FY2018-FY2020 Total Diet Study element-results ingest so future source ingests have a stable destination for this food matrix. FDA reports this item as TDS Food 81, “Watermelon, raw/frozen.” FY2018-FY2020 TDS Elements Analytical Results

Why this commodity accumulates heavy metals

Watermelon is a cucurbit fruit with a high water content (approximately 92 percent by weight) and a large physical volume. Both characteristics limit heavy metal accumulation on a per-gram basis: metals taken up from soil by the root system are distributed across a large mass of dilute fruit tissue. The thick outer rind provides an additional physical barrier that restricts metal translocation into the edible flesh. Watermelon is therefore among the lower-risk food matrices on the wiki for most heavy metals. The FDA TDS FY2018-FY2020 data (n=27) consistently show zero or near-zero values for Pb, Cd, Cr, and tHg across the full distribution, with only Ni (reaching 79 ppb at maximum), tAs (reaching 6.8 ppb at maximum), and Cd (reaching 2.6 ppb at maximum) showing any non-zero observations at the upper tail (FY2018-FY2020 TDS Elements Analytical Results). The Ni signal is consistent with low-level background Ni in cucurbit crops. The tAs signal at trace levels is not unexpected for fruit grown on soils with any background arsenic. Root-level uptake from contaminated soils is the operative pathway for all detected metals; there is no aquatic bioaccumulation or manufacturing-related metal pathway for fresh watermelon.

Heavy metal contamination profile

Per-analyte snapshot derived from the machine-readable contamination_profile in the frontmatter above. data gap indicates the literature has been reviewed for this commodity-analyte combination and no usable occurrence data was found (a finding, not a placeholder). The Key sources column shows the top 2-3 contributing sources by year and sample size, with numbered wikilink aliases.

FDA TDS FY2018-FY2020 Evidence

The normalized row-level data for this TDS food is stored in data/evidence/fda_tds_fy2018_2020_element_results_samples.csv, with per-food/per-analyte summaries in data/evidence/fda_tds_fy2018_2020_summary_by_food_analyte.csv. Concentrations are retained as FDA reported them, with the reporting-limit column preserved separately; reported zeroes are not rewritten as <LOD unless a source explicitly says to do so. FY2018-FY2020 TDS Elements Analytical Results

Routing

This node is linked from the ingredient index and the FDA TDS source routing table.

Contamination Profile State

Per-analyte state — populated, in progress, or declared data gap — is carried authoritatively in the machine-readable contamination_profile frontmatter and the contamination-profile table above. Ingredient-level values belong here; finished-product values belong on the relevant product-category page.

FDA TDS FY2018–FY2020 source observations

FDA measured the prepared foods named below. Each row describes that food and preparation, not every form of this ingredient. Values are µg/kg (ppb) on the FDA sample basis. ND means not detected; it is not a measured zero. Reporting limits can vary between composites. FY2018-FY2020 TDS Elements Analytical Results

Ranges by source, region, and variety

FDA TDS FY2018-FY2020 data (n=27) show that the vast majority of watermelon samples are at or below detection limits for all analytes (FY2018-FY2020 TDS Elements Analytical Results). Where detectable, Ni reached a maximum of 79 ppb, tAs a maximum of 6.8 ppb, and Cd a maximum of 2.6 ppb. These distributions suggest that elevated values are rare events, likely associated with specific growing conditions rather than being characteristic of the commodity category as a whole. No geographic or varietal breakdown for watermelon heavy metals is available in the current corpus.

Processing effects

Fresh watermelon consumed raw undergoes no processing steps that alter metal concentrations. Watermelon juice and watermelon-based beverages produced by pressing and filtering concentrate metals in proportion to water reduction only minimally, as the high initial water content of the fruit means that juice yield is high and solid residue is low. Freezing (the form in the TDS description “Watermelon, raw/frozen”) does not alter metal concentrations. No cooking or thermal processing is conventionally applied to watermelon in its primary use as a fresh fruit.

Ingredient-derivative risk

Watermelon is used primarily as a fresh fruit. Processed derivatives include watermelon juice, watermelon extract (used in beverages and supplements), watermelon rind pickles, and freeze-dried watermelon powder. The rind carries a different metal profile than the flesh because it is the outer structural tissue closest to the soil interface; rind-specific metal data are not in the current corpus. Freeze-dried watermelon powder concentrates metals proportionally to water removal but the low initial metal content of the flesh means concentrations remain low even after dehydration.

Mitigation options

Sourcing levers

No quantified data on this lever in the current corpus; section will be expanded when relevant evidence is ingested.

Agronomic levers

No quantified data on this lever in the current corpus; section will be expanded when relevant evidence is ingested.

Processing levers

No quantified data on this lever in the current corpus; section will be expanded when relevant evidence is ingested.

Formulation levers

No quantified data on this lever in the current corpus; section will be expanded when relevant evidence is ingested.

Testing and QC levers

Given the consistently near-zero concentrations in the TDS data, routine lot-level heavy metal testing of fresh watermelon for commercial food manufacturing is unlikely to yield actionable signals under normal supply-chain conditions. Testing would be warranted when watermelon is sourced from geographies with known soil contamination or industrial co-location.

Packaging and storage levers

No quantified data on this lever in the current corpus; section will be expanded when relevant evidence is ingested.

Regulatory limits that apply

The European Union applies maximum levels for Pb (0.10 mg/kg, or 100 ppb) and Cd (0.050 mg/kg, or 50 ppb) to fresh fruit under EU Regulation 2023/915 maximum levels for contaminants in food. These limits apply to watermelon as fresh fruit sold in the EU. No FDA action level specific to watermelon or cucurbit fruits is in force. Codex Alimentarius — Maximum Levels for Cadmium in Food provides the international Codex Cd maximum for vegetables and certain fruits. The observed concentrations in the TDS data are substantially below applicable regulatory limits.

Interpretation of source evidence

Source observations and population estimates are different. A non-detect supplies a reporting-limit bound for the tested composites. It does not show that this ingredient contains zero metal. Where a previous profile lacked matching source, species or basis support, its generic concentration has been withdrawn; the available source evidence is kept below.

Pb. FDA source observations are non-detects at the reporting limits below. They do not estimate a zero population concentration; other literature remains separate context.

Other previously cited literature is retained as context; it does not establish the withdrawn numerical profile: Assessment of Potentially Toxic Elements in Four Melon Fruit Varieties Grown in the Ganges and Yamuna River Basin.

tHg. FDA source observations are non-detects at the reporting limits below. They do not estimate a zero population concentration; other literature remains separate context.

Cr. FDA source observations are non-detects at the reporting limits below. They do not estimate a zero population concentration; other literature remains separate context.

Other previously cited literature is retained as context; it does not establish the withdrawn numerical profile: Assessment of Potentially Toxic Elements in Four Melon Fruit Varieties Grown in the Ganges and Yamuna River Basin.

U. FDA source observations are non-detects at the reporting limits below. They do not estimate a zero population concentration; other literature remains separate context.

References

Works cited in this page’s text, in first-appearance order. See Sources for this page’s source inventory. Each title links to its source record, which carries the ingest receipt, the extracted values, and the file hash of the document it was built from.

1. FY2018-FY2020 TDS Elements Analytical ResultsU.S. Food and Drug Administration · FDA Total Diet Study · 2022 · www.fda.govDataset
2. Assessment of Potentially Toxic Elements in Four Melon Fruit Varieties Grown in the Ganges and Yamuna River BasinElbagory M, Abd El-Aziz MA, Omara AED, Abou Fayssal S, and Kumar V · Horticulturae · 2025 · doi.org/10.3390/horticulturae11020216Peer-reviewed

Sources

Auto-generated from source-page frontmatter. The "Used on this page for" column is populated by the orchestrator's POPULATE-SOURCE-LEGEND action; pending entries appear as *[awaiting synthesis]*.

Update history

No substantive edit history is available in this build. The full commit record is available in git.