Akkaya 2025 - Marmara fishery-product metals

Akkaya and colleagues measured Pb, Cd, Hg, total arsenic, and Cu in 625 fishery-product and mussel samples from the Marmara region of Türkiye. The study also assessed Salmonella spp. and Listeria monocytogenes, but the HMI-relevant occurrence evidence is the metal testing and risk modeling. Arsenic speciation is not analytically measured: the authors measured total arsenic and derived Asin by assuming it was 10% of total arsenic.

Key numbers

Table 1 reports sample counts and size ranges:

The abstract reports that among all 625 samples, results exceeding permissible limits were Hg 36.96% (CI95 = 33.27-48.81), Pb 9.76% (CI95 = 7.67-12.34), and Cd 19.36% (CI95 = 16.45-22.64). It states that crabs remained compliant, and that anchovy, sardines, bluefish, shrimps, and octopus met EU Cd limits.

Table 5 reports non-compliant/total sample counts under Regulation (EU) No. 915/2023:

Figure 2 presents means ± SD in mg/kg, but the PDF does not print exact numeric means in the text layer. The text states that shrimps had higher derived Asin levels than crabs (p < 0.05), while squids had higher derived Asin than octopus and lower Pb than octopus (p < 0.05). It also states that mussels had high derived Asin, Cd, and Hg, while shrimps, squids, and octopus had significant derived Asin, Cd, Hg, and Pb.

The discussion reports exact concentration ranges and values for selected groups. Mussel samples had Pb 0.003-1.789 mg/kg, Cd 0.056-1.473 mg/kg, and derived Asin 0.685 to 7.827 mg/kg; Hg was detected in mussels at 0.269 mg/kg, and the highest reported mussel concentrations were Cu 5.122 mg/kg and As 7.827 mg/kg. Fish samples had Cd 0.003 to 0.429 mg/kg. Red mullet Hg was reported as 0.27 ± 0.17 mg/kg, and sardines followed the order Hg > Pb, with Cd not detected.

For risk metrics, the text states that adult THQ values remained below 1 in all samples. For children, THQ exceeded 1 for shrimps (THQAsin = 1.948), crabs (THQAsin = 1.094), squids (THQAsin = 1.729), and octopus (THQAsin = 1.226). Children’s HI exceeded 1 for shrimps, mussels, crabs, squids, and octopus; adult HI exceeded 1 only for shrimps.

Table 3 reports ICP-OES LoQ values: As 0.023 mg/kg, Cd 0.033 mg/kg, Pb 0.0013 mg/kg, Cu 0.028 mg/kg, and Hg 0.047 mg/kg. QC recoveries for the three concentration levels ranged from As 99.8-101%, Cd 99-101.8%, Pb 99.9-100.8%, Cu 99.88-100.4%, and Hg 99.2-101.6%.

Methods (brief)

Samples were collected from provinces in the Marmara region between March 2020 and November 2022 and transported under cold-chain conditions. Heavy metals were analyzed by ICP-OES using a Thermo iCAP 6000 series instrument; Hg was prepared with a hydride generation system, while As, Cu, Pb, and Cd were analyzed without the hydride system. Sample aliquots of 0.5 g were digested by wet combustion with nitric acid and perchloric acid. Results were expressed as mg/kg of sample, with triplicate measurements. The authors measured total arsenic and calculated inorganic arsenic by assuming Asin was 10% of total arsenic; this page therefore treats arsenic as measured total arsenic plus source-derived Asin, not as measured iAs speciation.

Implications

This source provides primary Marmara-region occurrence evidence for seafood, fresh marine fish, mussels, crustaceans, and cephalopods. It is especially useful for total Hg compliance prevalence and for mussel Cd/Pb/derived-arsenic ranges, but downstream routing should avoid treating the Figure 2 bar chart as extractable exact means unless the underlying data table is obtained. The derived Asin values should remain flagged as an assumption from total arsenic, and total Hg must not be promoted to methylmercury.

Verification notes

• PDF text extracted with pdftotext -layout; title page, sample table, methods, validation table, regulatory-limit table, non-compliance table, discussion, and supplementary-materials notice were readable.
• DOI 10.3390/toxics13030153, raw handle MFK_toxics-13-00153-v2, and cite-key checks found no existing source page before creation.
• Figure 2 was rendered from the PDF because it is the only place where mean ± SD metal concentrations are plotted. The figure has bars but no printed numeric mean labels, so exact mean values are not transcribed from the figure.
• Table 1 sample counts, Table 3 LoQs/recoveries, Table 5 non-compliance counts and CIs, and discussion-reported ranges/values were checked against extracted text. Units are preserved as mg/kg; no conversion was performed.
• Speciation: Hg is total/unspecified Hg (tHg), not MeHg. Arsenic was measured as total arsenic; Asin values are source-derived using a 10% total-arsenic assumption, not measured inorganic-arsenic speciation.
• Brand firewall: samples are grouped by fishery product/species and no product brand values were reported.
• Frontmatter slugs were checked against docs/gpt-collaboration/taxonomy-snapshot.md; missing narrow closed-vocabulary slugs include anchovy, surmullet, horse mackerel, sardine, whiting, bluefish, red mullet, mussel, shrimp, crab, squid, and octopus rows, so broad seafood/fish/shellfish routing is used.

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.