Sixto et al. 2023 - Arsenic, cadmium, and lead in potatoes and sweet potatoes

Sixto et al. validated methods for As, Cd, and Pb in potatoes and sweet potatoes, then applied them to peeled and whole samples from Uruguay’s main wholesale produce market. The paper is direct occurrence evidence for the root-and-tuber vegetable row because it distinguishes peeled from whole potatoes and sweet potatoes on a fresh-weight basis. Cadmium appeared consistently in whole sweet potato pools but not peeled sweet potato pools, and lead was more often detected in peeled potato pools than in whole pools.

Key numbers

All concentration results are reported as mg/kg fresh weight, mean +/- standard deviation, with n=3 analytical replicates per pooled sample.

Method figures of merit were reported separately for potato and sweet potato. LOD/LOQ were 0.0033/0.011 mg/kg for As in potato, 0.0043/0.011 mg/kg for As in sweet potato, 0.00043/0.0013 mg/kg for Cd in both matrices, and 0.0060/0.018 mg/kg for Pb in both matrices.

Methods (brief)

Sampling took place at Uruguay’s Metropolitan Agrifood Market, the country’s main wholesale/distribution center for fruit and vegetables. Approximately 1 kg, or five pieces, of each vegetable was collected per sample and transported to the lab within one hour. Samples were collected in February and in July-August between 2018 and 2020; sweet potatoes came from Salto and Canelones departments, and potatoes from San Jose and Canelones.

Samples were chopped with a ceramic knife, dried, ground, sieved to less than 1 mm, digested with nitric acid, and analyzed after microwave-assisted digestion. Cd and Pb in potatoes and sweet potatoes, and As in sweet potatoes, were measured by ETAAS. As in potatoes was measured by hydride-generation microwave-induced plasma optical emission spectrometry because ETAAS matrix interference could not be resolved for potato.

Implications

For the root-and-tuber vegetable product row, this source adds fresh-weight occurrence data from the Uruguayan market and directly distinguishes peeled from whole product forms. Whole potatoes contained quantifiable Cd in all three pools, while Pb was not detected or below LOQ. Whole sweet potatoes contained quantifiable Cd in all three pools and Pb below LOQ. Peeled potatoes had quantifiable Cd in all five pools and quantifiable Pb in three of five pools; peeled sweet potatoes mostly had ND or <LOQ results, with one quantifiable Pb result.

For standards and app work, the values should remain market-specific and basis-specific. They should not be silently pooled with dry potato products, cooked products, non-Uruguayan market samples, or inorganic-arsenic datasets.

Wiki pages this source may touch

• root-tuber-vegetables
• potatoes
• sweet-potato
• root-vegetables
• arsenic-total
• cadmium
• lead

Verification notes

• Auto-fetched ingest, 2026-05-31. The filename targeted total arsenic in root/tuber vegetables; the actual source reports total/unspecified As along with Cd and Pb.
• Speciation: arsenic is total/unspecified As; do not route as inorganic arsenic.
• Basis: all concentration values are mg/kg fresh weight. The paper’s peeled and whole product forms should remain distinct in any downstream pooling.
• Geographic scope: Uruguay market samples from UAM; keep separate from US-market benchmark pools unless governance documents cross-market use.

Page history

The five most recent substantive edits to this page. The full version history lives in git; when DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.