Voegborlo et al. 1999 — Mercury, cadmium, and lead in Libyan canned tuna

Voegborlo and colleagues measured total mercury, cadmium, and lead in canned tuna fish from Misurata, Libya. Mercury was measured by cold-vapour atomic absorption spectrophotometry, while cadmium and lead were measured by flame atomic absorption spectrophotometry. Results are reported in mg g-1 wet weight in the extracted text layer, with mercury detected in 20 of 50 samples and cadmium and lead detected in 12 of 50 samples.

Key numbers

Table 4 reports mean contents of mercury, cadmium, and lead in canned tuna samples:

The discussion states that all but two mercury-detected samples were below the 0.5 mg g-1 FAO/WHO limit cited by the source; the two higher mercury values were 0.55 and 0.66 mg g-1. The abstract reports the same ranges and mean values for mercury, cadmium, and lead.

Methods (brief)

Fifty canned tuna samples were obtained from a commercial tuna canning factory in Misurata, Libya. After opening each 5 kg can, oil was drained and the meat was homogenized in a food blender with stainless-steel cutters. Mercury digestion used 1 g homogenized sample with HCl, HNO3, and H2SO4 before cold-vapour AAS; lead and cadmium digestion used about 10 g sample with H2O2 and HNO3 before flame AAS. Mean spike recoveries were 97.2% for mercury, 99.8% for lead, and 99.3% for cadmium.

Implications

This source contributes Libya/Mediterranean canned-tuna occurrence data for total mercury, cadmium, and lead. It is useful for canned-fish and predatory marine fish routing, but mercury should remain total-Hg context unless a later source provides methylmercury speciation or a documented conversion rule. The source does not report arsenic, methylmercury, inorganic mercury, or tin.

Verification notes

• PDF text extracted with pdftotext -layout; the title page, abstract, methods, recovery tables, Table 4, and discussion were readable, though the text layer renders “fish” with a ligature artifact.
• The PDF prints PII S0308-8146(98)00008-9; DOI was derived as 10.1016/S0308-8146(98)00008-9. DOI/PII, raw handle MFK_voegborlo1999, and cite-key checks found no existing source page before creation.
• All concentration values in Key numbers were checked against Table 4 and the abstract. Units are preserved as mg g-1 wet weight as rendered in the extracted text; no conversion to mg/kg or ppm was performed.
• Speciation: mercury is total mercury. The source discusses methylmercury historically but does not measure MeHg.
• Brand firewall: the source uses factory/canned-tuna sampling, not consumer brand rankings.
• Frontmatter product and ingredient slugs were checked against docs/gpt-collaboration/taxonomy-snapshot.md; no new slug was invented.

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.