Yoplac-Navarro et al. 2026 — Metals in Peruvian avocados: ecological and health risk across 8 regions
This study quantified As, Cd, Cr, Hg, Ni, and Pb in soils and avocado pulp across eight major Peruvian producing regions using MP-AES, applying probabilistic risk assessment (Monte Carlo simulation) from a One Health perspective. The study is directly relevant to an active food safety issue: in 2025 the EU RASFF system generated nine alerts for Peruvian avocados exceeding the EU Cd maximum limit (0.05 mg/kg). Results show substantial regional variation in soil metal concentrations, with Ica and La Libertad — the two highest-volume export regions — showing the most concern. Bioaccumulation factors below 1 confirm that avocado pulp does not concentrate metals from soil, but absolute fruit concentrations still varied widely enough to produce exceedances in some samples.
Key numbers
Soil concentrations (mean ± SD, mg/kg, across all regions):
- As: 76.17 ± 17.35 mg/kg (notably elevated; Peru’s mining legacy)
- Cd: 0.55 ± 1.04 mg/kg
- Pb: 25.35 ± 6.02 mg/kg
Avocado fruit (pulp) concentrations (mg/kg dry weight; ranges across all samples):
- As: <0.003 to 0.192 mg/kg (<3 to 192 µg/kg)
- Cd: <0.005 to 0.130 mg/kg (<5 to 130 µg/kg); EU ML = 0.05 mg/kg — some samples exceeded this
- Cr: below detection limit throughout (<0.003 mg/kg)
- Hg: <0.005 to 0.428 mg/kg (<5 to 428 µg/kg); wide range with regional clustering
- Ni: <0.005 to 0.172 mg/kg (<5 to 172 µg/kg)
- Pb: <0.005 to 0.396 mg/kg (<5 to 396 µg/kg)
Bioaccumulation (BAF < 1 for all metals): confirms low soil-to-fruit translocation overall.
Ecological risk (Igeo and ER indices): soils ranged from uncontaminated to moderately contaminated; low ecological risk designation.
Health risk: Hazard quotient (HQ) and hazard index (HI) < 1 for all metals under the probabilistic analysis — indicating low non-carcinogenic risk at typical consumption. Cancer risk for Pb < 10⁻⁶ (non-significant); cancer risk for Cd in the 10⁻⁴ range (acceptable but at the upper boundary of acceptable risk).
Regional breakdown: Ica and La Libertad (dominant export regions) showed elevated soil As and Pb; Huancavelica showed elevated soil Cd. Avocado fruit values were available by region in the full dataset (Tables 2–4 of the original), but were not fully extractable from text conversion.
Sample size: 190 total (soil + fruit paired); effectively n=95 avocado fruit samples across 8 regions.
Methods (brief)
MP-AES (Agilent 4100) with ICP method. Acid digestion (HNO3/H2O2/HCl, HotBlock system). Analytical laboratory accredited to ISO/IEC 17025:2017 (LABISAG, Universidad Toribio Rodríguez de Mendoza). Probabilistic risk assessment via Monte Carlo simulation fitting regional distributions (log-normal or empirical). No arsenic speciation — total As reported. Hg by MP-AES at 253.652 nm (total Hg; no MeHg speciation).
Implications
Certification: The EU RASFF cadmium alert history for Peruvian avocados makes this study directly actionable for supply-chain guidance. Cd concentrations up to 130 µg/kg (0.130 mg/kg) against an EU ML of 50 µg/kg (0.05 mg/kg) indicate that a proportion of Peruvian avocado lots do not meet EU standards. HMT&C standards for avocado-inclusive products should account for origin variability. Hg range (<5 to 428 µg/kg) is broad and warrants lot-level monitoring in Peru-origin supply chains.
Courses: Strong teaching case for the intersection of mining activity, agricultural soil quality, and food safety compliance. Peru’s dual identity as major avocado exporter and major mining nation creates a structural tension relevant to supply-chain risk curriculum.
App: Geographic breakdown (8 regions) provides the data structure for regional sub-profiles on the avocado ingredient page. La Libertad and Ica represent the bulk of export volume, so their regional distributions should anchor the app’s default risk estimates for avocado in the absence of known origin.