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 original field study investigated cadmium and lead in sweet potato cultivars to identify low-accumulating varieties suitable for safe production on contaminated farmland and to quantify consumer health risk using estimated daily intake, target hazard quotient, and hazard index metrics. Fourteen cultivars spanning starch, edible, and purple types were grown on severely Cd/Pb-polluted soil in Liuyang, Hunan (total Cd 3.31 mg/kg; Pb 124.81 mg/kg). Concentrations were measured in root, shoot, peel, and flesh; yields and metal accumulation per hectare were also determined. Results were interpreted against Chinese GB 2762-2017 and Codex maximum levels. Figures and tables provide core data: Table 2 lists tissue concentrations; Figure 2 compares types; Table 3 reports EDI/THQ/HI; Figure 3 summarizes whole-plant accumulation. These findings directly inform HTMC cultivar selection and risk communication for crops grown on impacted soils.
Who was studied?
The “participants” were fourteen commercially relevant sweet potato cultivars common in Mid-South China, including six starch types, five edible types, and three purple types, supplied by the Hunan Academy of Agricultural Sciences. Plots (3×3 m; 40 plants; triplicate) were established and managed with standard practices. Human exposure modeling targeted local adult consumers using provincial intake data to estimate risks from eating shoots versus flesh. Within this agronomic–public health framework, the study sought cultivars whose flesh meets food standards for cadmium and lead, while recognizing that shoot consumption may pose a higher risk.
Most important findings
| Critical point | Details |
|---|---|
| Low-accumulating flesh cultivars identified | Flesh Cd and Pb in Shangshu 19, Sushu 24, Yushu 98, and Xiangshu 98 were below Chinese MCLs (Cd ≤0.1 mg/kg; Pb ≤0.2 mg/kg), making them candidates for safe flesh consumption on contaminated soils (Table 2). |
| Universal shoot exceedances | All cultivars’ shoots exceeded vegetable MCLs for Cd (≥0.2 mg/kg) and Pb (≥0.3 mg/kg), confirming shoots are the highest-risk edible component. |
| Type matters for translocation | Starch types had significantly lower flesh Cd/Pb and higher shoot Cd/Pb than purple and edible types, indicating stronger retention in foliage and reduced translocation to tubers. |
| Tissue distribution pattern | Cd: shoot > root > peel > flesh; Pb: root > shoot > peel > flesh, explaining why tuber flesh often meets standards while shoots rarely do. |
| Health risk differentials | For shoots, HI frequently >1 (0.93–2.78), driven mainly by Cd (55–86% of HI); for flesh, HI <1 across all cultivars (0.048–0.193), indicating acceptable risk from flesh alone. |
| Estimated intake vs. tolerable limits | Shoot EDI for Cd (0.51–2.27 μg/kg/day) can exceed PTWI; flesh EDI for Cd and Pb stayed within tolerable ranges, reinforcing “flesh-only” guidance. |
| Accumulation and biomass trade-offs | Shoots accounted for 75–95% of total plant Cd and ~48–75% of Pb; yet several low-accumulating flesh cultivars also delivered competitive root yields (e.g., Shangshu 19 highest root yield). |
| Soil–plant linkage | Flesh Cd correlated with DTPA-extractable soil Cd (r=0.667), and shoot Pb with DTPA-Pb (r=0.631), indicating bioavailability metrics can predict edible-tissue contamination (Table 4). huang2020 |
| Processing/handling cue | Peels had 1.18–4.44× Cd and 1.29–6.79× Pb vs. flesh, highlighting peeling as a risk-reduction step. |
| Standards alignment | Only Yushu 98 met stricter Codex limits for both metals in flesh; four cultivars met Chinese limits, suggesting market-specific certification thresholds matter. |
Key implications
For regulators, starch-type cultivars provide a practical pathway to maintain production while minimizing flesh contamination; certification should require cultivar-specific verification of flesh Cd/Pb levels relative to national or Codex limits, prohibit shoot sales for food, and mandate peel removal guidance. Industry can prioritize Shangshu 19, Sushu 24, Yushu 98, and Xiangshu 98, track soil DTPA-Cd/Pb as predictors, and divert shoots to nonfood uses. Research should validate performance across soils and elucidate translocation mechanisms to refine HTMC screening.
Citation
Huang F, Zhou H, Gu J, et al. Differences in absorption of cadmium and lead among fourteen sweet potato cultivars and health risk assessment. Ecotoxicology and Environmental Safety. 2020;203:111012. doi:10.1016/j.ecoenv.2020.111012
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.
