Laser ablation electrothermal plasma optical emission spectrometry (LAEP-OES) was validated for total mercury measurement in fish tissue by comparison against ICP-OES as a reference method, using 102 actual fish specimens purchased from Japanese markets. Multiple fish species were included; tuna is specifically highlighted. The study provides both a method validation and real food concentration data for total Hg in commercially available Japanese market fish.
Key numbers
- n = 102 fish specimens from Japanese markets
- Total Hg concentrations: specific per-species values in full paper
- Method comparison: LAEP-OES vs ICP-OES correlation and bias data in full paper
- Species composition: tuna and other fish species (exact breakdown in full paper)
Methods (brief)
LAEP-OES (laser ablation electrothermal plasma optical emission spectrometry) for total Hg in solid fish tissue. Reference method: ICP-OES (also measures total Hg). Neither method provides MeHg speciation — both report total Hg (tHg). Therefore all Hg values from this study should be recorded as tHg, not MeHg. Japanese market retail fish; provenance of fish origin not specified at classification stage.
Implications
Certification: Actual total Hg occurrence data in Japanese market tuna and other fish species. For Hg in seafood, MeHg is typically 90–100% of tHg in predatory fish; however, this paper does not speciate, so values should be labelled tHg. The MeHg fraction can be inferred from species-specific literature but not from this study alone. Courses: Demonstrates LAEP-OES as a potential high-throughput solid-sample method for Hg screening; illustrates total-vs-speciated distinction for Hg in fish. App: tHg occurrence data for tuna/fish from Japanese markets. Japan regulatory context: Ministry of Health limit for total Hg in fish is 0.4 ppm (400 ppb) general fish, with stricter limits for specific species. Microbiome: Total Hg in fish is the precursor to MeHg dietary exposure; gut demethylation of MeHg is microbiome-dependent.