Haseeb-ur-Rehman 2023 - metals in Pakistani export seafood

Haseeb-ur-Rehman and colleagues measured metals in 400 export-quality seafood samples from Pakistani processing plants. The study reports edible-portion concentrations in mg kg-1 w.w for fish, crustaceans, and cephalopods. Mercury was analyzed and was not detected in any sample; the page therefore treats mercury as total mercury (tHg) nondetect context, not as methylmercury.

Key numbers

• Sample frame: 50 samples each of Penaeus monodon, Portunus pelagicus, Loligo duvauceli, Sepia recurvirostra, Cynoglossus bilineatus, Otolithes ruber, Lepturacanthus savala, and Nemipterus japonicus.
• Mercury: Table 2 note states “Mercury was not detected in any of the samples”; the Results text identifies the detection level as 0.01 mg kg-1.
• P. monodon mean concentrations, mg kg-1 w.w: Cd 0.038, Pb 0.4, Ni 1.2, Fe 115, Zn 15, Mn 3.4, Cu 12; ranges were Cd 0.034-0.040, Pb 0.2-0.6, Ni 0.9-1.5, Fe 109-123, Zn 14-18, Mn 2.7-4.5, Cu 10-15.
• P. pelagicus: Cd 0.032, Pb 0.6, Ni 0.04, Fe 266, Zn 5, Mn 2.8, Cu 17; ranges were Cd 0.026-0.040, Pb 0.2-1, Ni ND-0.1, Fe 256-282, Zn 3-6, Mn 2-4.0, Cu 14-20.
• Cephalopods: L. duvauceli means were Cd 0.066, Pb 0.8, Ni 0.3, Fe 21, Zn 4, Mn 0.8, Cu 12; S. recurvirostra means were Cd 0.097, Pb 0.3, Ni ND, Fe 25, Zn 4, Mn 0.6, Cu 9.
• Fish: C. bilineatus means were Cd 0.064, Pb 0.6, Ni ND, Fe 26, Zn 2, Mn 0.6, Cu 6; O. ruber means were Cd 0.05, Pb 0.4, Ni 0.02, Fe 44, Zn 1, Mn 0.7, Cu 2.
• Fish continued: L. savala means were Cd 0.03, Pb 0.7, Ni ND, Fe 29, Zn 4, Mn 2.5, Cu 9; N. japonicus means were Cd 0.057, Pb 0.4, Ni ND, Fe 22.4, Zn 5, Mn 7.4, Cu 6.
• Category-range comparison table for this study: fish Hg ND, Cd 0.03-0.06, Pb 0.36-0.67, Ni 0.003-0.025, Fe 22.36-44.96, Zn 1.43-4.45, Mn 0.64-7.39, Cu 2.01-5.63 µg/g, w.w; crustaceans Hg ND, Cd 0.03-0.04, Pb 0.399-0.635, Ni 0.044-1.195, Fe 115.72-266.36, Zn 4.536-15.389, Mn 2.84-3.40, Cu 11.83-16.60; cephalopods Hg ND, Cd 0.07-0.10, Pb 0.31-0.84, Ni ND-0.31, Fe 21.01-25.15, Zn 3.56-4.33, Mn 0.56-0.77, Cu 9.30-12.44.

Methods (brief)

Frozen seafood samples from export consignments were thawed, dissected for edible tissue, homogenized, and stored at -18 °C before analysis. Homogenized edible tissue (2 ± 0.01 g) was acid-digested. Mercury was measured by cold-vapour atomic absorption spectroscopy; cadmium and lead were measured by graphite furnace atomic absorption spectroscopy with Zeeman background correction; nickel, iron, zinc, manganese, and copper were measured by flame atomic absorption spectroscopy. Quality control used standard solutions, reagent blanks, certified reference material LGC7164 brown crab meat paste, and one CRM per batch of 10 samples.

Implications

Certification (HMTc): This source contributes wet-weight occurrence data for seafood, shellfish, cephalopods, and marine fish in export-quality Pakistani supply chains. It is especially useful because it separates total mercury nondetects from other metals and does not report MeHg.

Courses: The paper is a strong example of seafood occurrence reporting with species-level sample sizes, means, standard deviations, ranges, CRM recoveries, and wet-weight basis.

App: The source can support product/ingredient profiles for seafood and shellfish with tHg nondetect context and quantified Cd, Pb, Ni, Fe, Zn, Mn, and Cu values.

Wiki pages this source may touch

• seafood
• fish
• shellfish
• molluscs
• seafood
• fresh-fish
• shellfish
• fish-marine-predatory
• fish-marine-non-predatory

Verification notes

• PDF text was extracted with pdftotext -layout to /tmp/hmi_row_1550.txt; Table 2, Table 4, Table 5, and the Methods were re-read before writing.
• Identity checks before creation: DOI 10.1016/j.marpolbul.2023.114581, raw handle MFK_metal-pollution-and-potential-human-health-risk, raw SHA-256 35927a13d569997080692ddf7020c6bfb5db552f7559bb773d93fa9e6297677a, and cite key haseeb-ur-rehman2023-pakistan-seafood-metals were searched in wiki/sources/ and evidence files; no existing source page was found.
• Units are preserved as mg kg-1 w.w and µg/g, w.w where printed; no conversion between equivalent units was made.
• Speciation: mercury is total mercury/nondetect context (tHg); no methylmercury values are reported or inferred.
• Brand firewall: samples came from processing plants/export consignments, but no plant or brand names are attached to values.
• Closed-vocabulary note: no crustacean or cephalopod product slug exists in the current snapshot, so shrimp, crab, squid, and cuttlefish route through broad seafood, shellfish, and molluscs context.

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.