Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. 
Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. What was studied?
This study supports heavy metal certification of potatoes by developing and validating simple, low-cost analytical methods for arsenic, cadmium, and lead in peeled and whole potatoes and sweet potatoes, then applying them in market-surveillance samples from Uruguay. Electrothermal atomic absorption spectrometry was used for Cd and Pb, and for As in sweet potato; hydride-generation nitrogen microwave induced plasma OES was required for As in potato due to matrix interference. Quantification limits achieved were 0.0013 mg/kg for Cd, 0.018 mg/kg for Pb, and 0.011 mg/kg for As, meeting or closely approaching AOAC reference criteria and remaining far below MERCOSUR/Codex maximum allowed levels (MALs: Cd 0.1 mg/kg, Pb 0.1 mg/kg, As 0.2 mg/kg where applicable). Results were compared against MALs to assess risk when consuming whole tubers, an increasingly common practice.
Who was studied?
Produce sold through Uruguay’s principal wholesale hub was targeted to mirror consumer exposure and inform heavy metal certification potato decisions. Randomized sampling at the Metropolitan Agrifood Market captured countrywide distribution: potatoes from San José and Canelones and sweet potatoes from Salto and Canelones. Pooled samples representing multiple producers were created to enable surveillance: three pools for whole potato and sweet potato, five pools for peeled potato, and eleven pools for peeled sweet potato, with standardized drying, grinding, and microwave-assisted nitric acid digestion to ensure method comparability. This design emphasizes population-level exposure rather than farm-specific effects and aligns with programmatic monitoring goals for HTMC.
Most important findings
| Critical point for HTMC | Detail and quantitative evidence |
|---|---|
| Method fitness for purpose | LOQs: Cd 0.0013 mg/kg; Pb 0.018 mg/kg; As 0.011 mg/kg. These are ≥5× below MAL for Pb and ~20× below MAL for As; precision and trueness met AOAC performance, enabling routine certification testing. |
| Regulatory benchmarks | MALs used: Cd 0.1 mg/kg; Pb 0.1 mg/kg (Codex/MERCOSUR); As 0.2 mg/kg in MERCOSUR. All measured values were more than threefold below MALs in most cases, supporting compliance determinations. |
| Potato—cadmium signal | Cd was detected in all whole potato pools at 0.0022–0.034 mg/kg and in peeled potatoes at 0.0022–0.016 mg/kg, suggesting low-level Cd uptake consistent with fertilizer-origin Cd yet below MAL. |
| Sweet potato—skin-associated metals | In whole sweet potato, Cd around 0.0022–0.0027 mg/kg and Pb frequently |
| Arsenic outcome | As not detected or not quantified in any potato or sweet potato pool, reducing immediate As concerns for HTMC in these matrices under current geography and practices. |
| Analytical practicality | As in potato required HG–MIP OES due to matrix effects observed with ETAAS; the nitrogen plasma system avoids expensive argon/acetylene and supports scalable surveillance in resource-limited labs. |
| Sampling strategy relevance | Pooling at the wholesale market provides representative, traceable surveillance; if a pool exceeds MAL, individual-source follow-up and on-farm soil/water testing can be triggered. |
Key implications
For heavy metal certification potatoes, primary regulatory impacts include affirming compliance against MALs while highlighting that certification claims should specify the matrix and preparation state. Certification requirements should mandate explicit peel-state labeling and periodic market-based pooled surveillance. Industry applications include skin-aware process controls for whole-tuber products. Research gaps involve cultivar, seasonality, and fertilizer-speciation effects. Practical recommendations are to prioritize Cd monitoring in potatoes, include whole-root assays for sweet potatoes, and adopt HG–MIP OES for As where matrix interferences compromise ETAAS.
Citation
Sixto A, Mollo A, Ibañez F, Pistón M. Inorganic contaminants (As, Cd, Pb) in peeled and whole potatoes and sweet potatoes. Agrociencia Uruguay. 2023;27:e1060. doi:10.31285/AGRO.27.1060
Heavy metals are high-density elements that accumulate in the body and environment, disrupting biological processes. Lead, cadmium, arsenic, mercury, nickel, tin, aluminum, and chromium are of greatest concern due to persistence, bioaccumulation, and health risks, making them central to the HMTC program’s safety standards.
Cadmium is a persistent heavy metal that accumulates in kidneys and bones. Dietary sources include cereals, cocoa, shellfish and vegetables, while smokers and industrial workers receive higher exposures. Studies link cadmium to kidney dysfunction, bone fractures and cancer.
Lead is a neurotoxic heavy metal with no safe exposure level. It contaminates food, consumer goods and drinking water, causing cognitive deficits, birth defects and cardiovascular disease. HMTC’s rigorous lead testing applies ALARA principles to protect infants and consumers and to prepare brands for tightening regulations.
Arsenic is a naturally occurring metalloid that ranks first on the ATSDR toxic substances list. Inorganic arsenic contaminates water, rice and consumer products, and exposure is linked to cardiovascular disease, cognitive deficits, low birth weight and cancer. HMTC’s stringent certification applies ALARA principles to protect vulnerable populations.
