Determination of Heavy Metal Levels and Assessment of L. monocytogenes and Salmonella spp. Presence in Fishery Products and Mussels from the Marmara Region, Türkiye

Overview

Akkaya and colleagues measured lead (Pb), cadmium (Cd), mercury (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 arsenic (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 inorganic arsenic (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.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git.