Altalib et al. 2025 — Heavy metals in imported frozen meat, Tripoli markets

This cross-sectional study measured lead (Pb), cadmium (Cd), chromium (Cr), and copper (Cu) in 30 imported frozen meat samples collected from retail markets in Tripoli, Libya. Samples included chicken (50% of total), beef (27%), and lamb (23%), sourced from Brazil, USA, Jordan, Spain, and Australia. Analysis was by Atomic Absorption Spectrophotometry (AAS) following acid digestion. All samples complied with the tabulated Libyan limits for Cd and Cr and with the study’s Cu reference level; one sample (3.3%) exceeded the tabulated Libyan Pb limit of 0.10 mg/kg. The study provides a baseline Pb, Cd, Cr, and Cu dataset for imported commercial meat in a North African market context.

Key numbers

All values are source-reported as mg/kg; the paper does not state a wet-weight/dry-weight conversion basis, and the Methods section digests a dried sample. Libyan standard limits: Pb 0.10 mg/kg, Cd 0.05 mg/kg, Cr 1.00 mg/kg.

Lead (Pb):

• Mean: 0.0145 mg/kg (14.5 µg/kg / 14.5 ppb)
• SD: 0.0480 mg/kg
• Minimum: 0.0020 mg/kg (2.0 ppb)
• Maximum: 0.2570 mg/kg (257 ppb) — one sample exceeded Libyan limit of 100 ppb
• 29 of 30 samples (96.7%) below 0.10 mg/kg; 1 sample (3.3%) above
• By meat type: chicken highest mean (0.02667 mg/kg), beef (0.0025 mg/kg), lamb (0.00212 mg/kg)
• By origin: Jordan highest mean (0.07446 mg/kg); others ranged 0.00200–0.00289 mg/kg

Cadmium (Cd):

• Mean: 0.0017 mg/kg (1.7 ppb)
• SD: 0.0003 mg/kg
• Minimum: 0.0010 mg/kg (1.0 ppb)
• Maximum: 0.0023 mg/kg (2.3 ppb)
• 100% of samples below Libyan limit of 0.05 mg/kg
• By meat type: chicken highest mean (0.00184 mg/kg), beef (0.00176 mg/kg), lamb (0.00151 mg/kg)

Chromium (Cr; total chromium — speciation not performed):

• Mean: 0.0244 mg/kg (24.4 ppb)
• SD: 0.0204 mg/kg
• Minimum: 0.0090 mg/kg (9.0 ppb)
• Maximum: 0.0830 mg/kg (83.0 ppb)
• 100% of samples below Libyan limit of 1.00 mg/kg
• Authors explicitly note that AAS cannot differentiate Cr(III) from Cr(VI); advanced speciation methods recommended

Copper (Cu; not regulated under Libyan standards):

• Mean: 0.5142 mg/kg; range: 0.1187–0.9233 mg/kg
• Highest mean in beef (0.7541 mg/kg); significant variation by meat type (p<0.001)

ANOVA results (one-way, p<0.05 significance threshold):

• Pb by meat type: p=0.217 (NS); Cd by meat type: p=0.297 (NS); Cr by meat type: p=0.535 (NS); Cu by meat type: p=0.000 (significant)
• No significant differences by meat cut or country of origin for any metal (p>0.05 for all)

Methods (brief)

Cross-sectional study; 30 samples collected Feb–May 2025 from Tripoli retail markets. Samples mechanically homogenized; 1.0 g dried sample digested with concentrated HNO₃ and perchloric acid or H₂O₂; diluted to 50 mL. Metals were measured by AAS; the instrument model and AAS subtype are not specified. Total chromium only; Cr(VI) speciation not performed. The paper states that 1000 mg/L stock solutions for Pb, Cd, Cu, and Cr were prepared by dissolving pure metal in nitric acid and diluting to 1 L. Statistical analysis: SPSS v26, one-way ANOVA. Sample size (n=30) is small; no LOQ/LOD values reported in the text; the single Pb exceedance sample is an outlier substantially above the distribution mean.

Implications

Certification: The source contributes occurrence data for imported frozen meat in Tripoli: one Pb maximum at 257 ppb, Cd at 1.0–2.3 ppb, total Cr at 9.0–83.0 ppb, and Cu at 118.7–923.3 ppb. The Cr data are total Cr only; the authors explicitly state that AAS cannot differentiate Cr(III) from Cr(VI). Jordan-origin samples had the highest Pb mean (74.46 ppb vs Brazil/USA/Spain/Australia at about 2–3 ppb), but country of origin was not statistically significant (p=0.795).

Courses: Useful case for illustrating the difference between a low sample-set mean and an individual outlier. The mean Pb is below the tabulated limit, while the maximum Pb value is 257 ppb (2.57× the tabulated Libyan limit).

App: Source-side inputs include beef, chicken, and lamb/processed-meat Pb means by meat type, overall Cd in the 1–2 ppb range, Cu below the study’s 1.0 mg/kg reference value, and total Cr 9–83 ppb without Cr(VI) speciation.

Wiki pages this source may touch

• beef
• chicken
• poultry
• meat
• meat-and-poultry
• beef-product
• poultry-product
• lamb-mutton
• processed-meats
• lead
• cadmium
• chromium
• copper
• chromium-hexavalent

Verification notes

• 2026-05-18 Codex merge-enhance: matched DOI/raw path to P0156, added full MFK raw handle/path and SHA-256 provenance, added Cu to frontmatter because the paper measures Cu, replaced nonexistent ingredients/lamb with existing broader meat/poultry ingredient slugs, and routed the sampled food forms to existing Category 11 product pages.
• The matrices: terms retain source-specific meat-cut wording (beef-muscle, chicken-muscle, lamb-muscle, processed-meat) because the common matrix list does not include a broad meat/poultry term, while sibling meat-source pages already use beef-muscle and chicken-muscle for edible muscle tissue.
• The paper contains repeated typographical uses of “Pd” where context and tables identify Pb (lead).
• The Results prose states that one Pb sample exceeded a “0.05 mg/kg” Libyan limit, but Table 1 and Table 2 give the Pb limit as 0.10 mg/kg; this page uses the tabulated 0.10 mg/kg value and flags the source-internal inconsistency.
• Product slugs beef-product, poultry-product, lamb-mutton, and processed-meats exist as Category 11 routing destinations, although the GPT taxonomy snapshot had lagged this category during the initial manual-fetch pass.

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.