Shavali-gilani et al. 2025 — Heavy metals in canned tomato paste, olives, and pickled cucumbers from the Tehran market
Shavali-gilani and colleagues measured eight metals (Cd, Cu, tAs, Fe, Pb, Sn, Zn, tHg) in 49 samples of canned tomato paste, canned olives, and canned pickled cucumbers from five popular brands sold in Tehran, Iran. Mercury was not detected in any sample. The reported mean lead content in all three product categories exceeded the Codex permissible limit of 0.1 mg/kg for canned products, while the other detected metals were within Codex/EU acceptable limits. Cadmium showed a statistically significant difference (p<0.05) across product types, with tomato paste highest.
Key numbers
- n=49 canned samples across three product categories (tomato paste, olives, pickled cucumbers) from five brands in Tehran (Methods, Materials and sample collection).
- Canned pickled cucumbers (mg/kg, mean ± SD): Pb 0.22 ± 0.08; Sn 0.11 ± 0.05; Cu, As, Fe, Zn, Hg, Cd all ND (Table 2).
- Canned tomato paste (mg/kg, mean ± SD): Pb 0.19 ± 0.07; Cu 0.16 ± 0.1; As 0.0005 ± 0.0004; Fe 0.48 ± 0.4; Sn 0.4 ± 0.2; Zn 0.0071 ± 0.007; Cd 0.008 ± 0.005; Hg ND (Table 2).
- Canned olives (mg/kg, mean ± SD): Pb 0.19 ± 0.04; Sn 0.32 ± 0.17; Cd 0.005 ± 0.001; Cu, As, Fe, Zn, Hg all ND (Table 2).
- Method LODs (µg/kg): Cd 0.09; As 0.8; Pb 0.7; Hg 0.5; Sn 1.4. Method LODs (mg/kg): Cu 0.05; Fe 0.2; Zn 0.1 (Table 1).
- Method LOQs (µg/kg): Cd 0.3; As 3.0; Pb 2.3; Hg 1.8; Sn 4.6. Method LOQs (mg/kg): Cu 0.15; Fe 0.8; Zn 0.4 (Table 1).
- Recovery (%): Cd 93.8; As 97.3; Pb 92.7; Hg 95.0; Sn 99.2; Cu 94.5; Fe 98.3; Zn 96.4 (Table 1).
- Cadmium in tomato paste was significantly higher than in canned olives or pickled cucumbers (Kruskal-Wallis, p≤0.05).
- Lead averages in all three product categories (0.19–0.22 mg/kg) reportedly exceed Codex 0.1 mg/kg canned-product limit; statistical test among the three found no significant difference between product types for Pb (p>0.05).
Methods (brief)
49 samples were homogenized in-can, digested in 1:1 H2O2 (30%):HNO3 (65%) in a 150 mL beaker until clear, filtered (0.45 µm), and modified with 170 µL H3PO4. Cu, Fe, Zn determined by flame AAS (Shimadzu AA-6300); Cd, As, Pb determined by graphite furnace AAS; Hg and Sn determined by ICP-MS (Agilent 7500-Ce). All analyses performed in triplicate. Hg LOD 0.5 µg/kg; Hg was not detected in any sample. Mercury and tin were both measured as total (no speciation reported); As was reported as total arsenic with no speciation. The paper does not specify which graphite furnace AAS program was used for each analyte beyond stated wavelengths. The authors did not perform speciation for arsenic or mercury.
Implications
- Certification (HMTc): Adds Iranian-market canned-product occurrence data for Pb, Cd, Sn, and tAs in three matrices (tomato paste, olives, pickled cucumbers) sampled at retail from five popular brands. Direct evidence for the canned-tomatoes and canned-vegetables product-category pages, with the lead-content outcome relevant to the tomato-paste and olives ingredient discussions.
- Courses: Useful as a case study on packaging migration as a heavy-metal source for QA and supply-chain audiences.
- App: Contributes occurrence data points to tomato-paste (Pb, Cd, Cu, Fe, Sn, Zn, tAs), olives (Pb, Cd, Sn), and cucumbers / dill-pickles (Pb, Sn).
Wiki pages this source may touch
- tomato-paste
- olives
- cucumbers
- dill-pickles
- canned-tomatoes
- canned-vegetables
- tomato-paste
- lead
- cadmium
- tin
- arsenic-total
- mercury-total
- codex-cadmium-mls
- eu2023-contaminants-maximum-levels
Page history
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