Overview
Wickrama-Arachchige and colleagues measured 36 elements in edible aquatic organisms sold in Sri Lankan local fish markets. The main PDF reports trophic-level summaries, tuna muscle-type comparisons, a yellowfin-tuna mercury comparison table, and yellowfin-tuna risk calculations. Species-level concentration tables are named as supplementary Tables S2 and S3; they were not bundled in the local PDF, so this page preserves the exact main-PDF values and flags the supplement as required for future species-level extraction.
The study reports total mercury measured by a mercury analyzer. For the human-health calculation, the authors assume all total Hg in yellowfin tuna is methylmercury; this page records that assumption as a source assumption and does not relabel the measured occurrence table as directly speciated MeHg.
Key numbers
Sample frame and methods:
| Field | Value |
|---|---|
| Individual organisms | 80 |
| Fresh samples | 36 |
| Species | 29 |
| Offshore pelagic species | 18 |
| Coastal/estuarine species | 11 |
| Yellowfin tuna samples | 7 |
| Skipjack tuna samples | 3 |
| Element concentration basis | mg/kg wet weight |
| EDXRF detection limit used for elements other than Hg | 1.0 mg/kg dry weight; half detection limit (0.5 mg/kg) used for values below detection in analysis |
| Yellowfin tuna consumption assumption | 3.8 g/day (0.0038 kg/day) |
| Adult body weight assumption | 60 kg |
Element groups used by the paper:
| Group | Elements |
|---|---|
| Essential but toxic in excess amount (EBTEs) | Sn, Fe, Cu, Cr, Zn, Se |
| Non-essential toxic elements (NETs) | As, Sb, Cd, Hg, Pb |
| Other elements detected/discussed | Ni, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Mn, Co, Br, Rb, Sr, Te, I, Hf, Ta, Pt, Au |
Main-PDF trophic-level summaries:
| Ecosystem | Element group | Lower trophic level | Middle trophic level | Higher trophic level | Source pattern |
|---|---|---|---|---|---|
| Offshore pelagic | EBTEs | 31.6 mg/kg | 31.0 mg/kg | 11.4 mg/kg | HTL < MTL < LTL |
| Offshore pelagic | NETs | 1.49 mg/kg | 1.86 mg/kg | 1.89 mg/kg | LTL < MTL < HTL |
| Offshore pelagic | Other elements | 7610.2 mg/kg | 10012.3 mg/kg | 6503.8 mg/kg | HTL < LTL < MTL |
| Coastal/estuarine | EBTEs | 23.6 mg/kg | 13.5 mg/kg | 8.82 mg/kg | HTL < MTL < LTL |
| Coastal/estuarine | NETs | 0.64 mg/kg | 1.99 mg/kg | 0.84 mg/kg | LTL < HTL < MTL |
| Coastal/estuarine | Other elements | 8457.1 mg/kg | 8052.8 mg/kg | 7296.3 mg/kg | HTL < MTL < LTL |
Element-order summaries reported in the main text:
| Ecosystem | Group | Increasing concentration order |
|---|---|---|
| Offshore pelagic | EBTEs | Cr < Se < Cu < Sn < Zn < Fe |
| Offshore pelagic | NETs | Pb < Sb < Cd < Hg < As |
| Offshore pelagic | Other abundant elements | Sr < Br < Si < Al < Mg < Ca < P < Cl < S < K |
| Coastal/estuarine | EBTEs | Cr < Se < Cu < Sn < Fe < Zn |
| Coastal/estuarine | NETs | Cd < Hg < Pb < Sb < As |
| Coastal/estuarine | Other abundant elements | Br < Sr < Si < Al < Mg < Ca < Cl < P < S < K |
Maximum-allowable-limit exceedance signals reported in the main text:
| Ecosystem | Element | Source MAL | Species reported above MAL |
|---|---|---|---|
| Offshore pelagic | Cr | 0.1 mg/kg wet weight | Rastrelliger kanagurta, Mobula kuhlii, Auxis thazard |
| Offshore pelagic | As | 3 mg/kg | Mobula kuhlii, Katsuwonus pelamis (1.5 kg), Rhizoprionodon acutus |
| Offshore pelagic | Cd | 0.05 mg/kg | Loligo duvauceli |
| Offshore pelagic | Pb | 0.2 mg/kg | Sardinella albella |
| Coastal/estuarine | As | 3 mg/kg | Lethrinus nebulosus, Lutjanus rivulatus |
Tuna muscle-type summaries from Figure 4 and the text:
| Species | Muscle type | EBTEs | NETs | Other elements | Hg note |
|---|---|---|---|---|---|
| Yellowfin tuna (Thunnus albacares) | White muscle | 11.5 +/- 3.65 mg/kg | 1.4 +/- 0.45 mg/kg | 10549.3 +/- 2978.4 mg/kg | The paper reports nearly equal Hg between white and red muscles |
| Yellowfin tuna (Thunnus albacares) | Red muscle | 37.1 +/- 16.6 mg/kg | 1.93 +/- 0.65 mg/kg | 11809.7 +/- 2122.6 mg/kg | The paper reports nearly equal Hg between white and red muscles |
| Skipjack tuna (Katsuwonus pelamis) | White muscle | 29.8 +/- 8.75 mg/kg | 2.45 +/- 0.45 mg/kg | 11911.9 +/- 3836 mg/kg | The paper reports higher Hg in white than red muscle |
| Skipjack tuna (Katsuwonus pelamis) | Red muscle | 76.6 +/- 6.77 mg/kg | 3.1 +/- 2.18 mg/kg | 10426.3 +/- 556.0 mg/kg | The paper reports higher Hg in white than red muscle |
Yellowfin tuna total-mercury findings:
| Finding | Value |
|---|---|
| Yellowfin tuna Hg sample count | 7 |
| Mean Hg in yellowfin tuna | 0.16 +/- 0.16 mg/kg wet weight |
| Hg range in yellowfin tuna | 0.02-0.43 mg/kg wet weight |
| Mean length/weight in the study’s Table 1 comparison row | 118 cm / 27 kg |
| Hg-body-weight regression | R2 = 85.7 |
| Hg-body-weight regression p value | 0.003 |
| ANOVA MS for Hg-body-weight relationship | 0.126 |
| ANOVA F for Hg-body-weight relationship | 29.97 |
| ANOVA DF for Hg-body-weight relationship | 1 |
Table 1 compares the study’s yellowfin-tuna Hg results with literature values:
| Mean Hg | Range | Mean length/weight | Method | Country | Ocean | Reference |
|---|---|---|---|---|---|---|
| 0.16 +/- 0.16 mg/kg | 0.02-0.43 mg/kg | 118 cm / 27 kg | Mercury analyzer (MA 3000, USA) | Sri Lanka | Indian Ocean | This study |
| 0.30 +/- 0.18 mg/kg | 0.021-0.98 mg/kg | 123.4 cm / 45.3 kg | Cold vapor system atomic absorption spectrophotometry | Sri Lanka | Indian Ocean | [24] |
| 0.26 +/- 0.29 mg/kg | - | - | Atomic absorption spectrophotometry | Sri Lanka | Indian Ocean | [19] |
| 0.51 +/- 0.33 mg/kg | - | 74.3 +/- 11.4 cm | Atomic absorption spectrophotometry | Baja California Sur, California | Eastern Pacific Ocean | [69] |
| 0.98 +/- 0.69 mg/kg | - | 92.2 +/- 19.5 cm | Atomic absorption spectrophotometry | Equatorial Zone | Eastern Pacific Ocean | [70] |
| 0.51 +/- 0.32 mg/kg | - | 22 kg / 109 cm | Advanced mercury analyzer (combustion analyzer ALTEC 254) | Mozambique channel | Western Indian Ocean | [71] |
| 0.70 +/- 0.49 mg/kg | - | 24 kg / 104 cm | Advanced mercury analyzer (combustion analyzer ALTEC 254) | Reunion Island | Western Indian Ocean | [71] |
| 0.77 mg/kg | 0.45-1.52 mg/kg wet weight | 29.0-50.8 kg | Inductively coupled plasma mass spectrometry | South Africa | South Atlantic | [29] |
| 2.75 +/- 0.98 mg/kg dry weight | 1.51-4.49 ng/g dry weight | 138.8 cm forked length / 58.7 kg | Cold vapor atomic absorption spectroscopy | West Africa | North Atlantic Ocean | [28] |
| 159 +/- 79 ng/g wet weight | 48-500 ng/g wet weight | 92 +/- 28 cm forked length / 16.8 +/- 13.3 kg | Cold vapor atomic absorption spectrometry | Brazil | Equatorial Atlantic Ocean | [67] |
Yellowfin-tuna risk calculations reported in the main PDF:
| Metric | Value |
|---|---|
| THQ-As | 0.22 +/- 0.07 |
| THQ-Sb | 0.019 +/- 0.003 |
| THQ-Cd | 0.0067 +/- 0.001 |
| THQ-Hg | 0.024 +/- 0.001 |
| THQ-Pb | 0.0016 +/- 0.0003 |
| Hazard index | 0.27 |
| EDI of NETs for Sri Lankan adults | 9.38 x 10^-5 +/- 1.58 x 10^-5 mg/kg bw/day |
| PTWI-As | 0.47 +/- 0.13 ug/kg bw/w |
| PTWI-Sb, PTWI-Cd, and PTWI-Pb | 0.05 +/- 0.008 ug/kg bw/w |
| PTWI-M-Hg | 0.05 +/- 0.02 ug/kg bw/w |
Methods (brief)
The authors purchased commonly consumed edible aquatic organisms from Sri Lankan local fish markets. Samples were transported on ice, dissected, and stored below -40 C. Heads, fins, and viscera were removed from small to medium specimens; approximately 200 g of muscle from the anterior dorsal region near the pectorals was collected from large fish. Tuna red and white muscles were separated for yellowfin and skipjack comparisons.
Most elements were analyzed using a Rigaku EDXL-300 energy-dispersive X-ray fluorescence spectrometer after freeze-drying, homogenization, binder mixing, and pellet preparation. Mercury was analyzed separately using a NIC MA-3000 Mercury Analyzer, with two replicates from one sample.
Stable isotope analysis was used to assign trophic-level patterns. Human-risk calculations for yellowfin tuna used 3.8 g/day yellowfin-tuna consumption for Sri Lankan adults and 60 kg body weight. The authors assumed all total Hg in yellowfin tuna was present as methylmercury for risk-assessment comparison.
Implications
This source supports broad seafood occurrence context for Sri Lankan market fish and shellfish, with a direct yellowfin-tuna total-Hg value and main-text summary signals for arsenic, cadmium, lead, chromium, and other elements across edible aquatic organisms. The main-PDF values are especially useful for fish-route context and for documenting that yellowfin-tuna Hg rose with body weight in this sample set.
The paper is not infant-formula evidence despite being located in an infant-formula methylmercury pull folder. It does not measure methylmercury directly; the MeHg risk calculation is derived from a source assumption that total Hg in tuna represents methylmercury. Species-level extraction should use the supplementary Tables S2-S3 if they are retrieved later.
Wiki pages this source may touch
- Fish — marine, predatory (tuna, swordfish, shark, king mackerel)
- Fish — marine, non-predatory (sardines, anchovies, salmon, cod)
- Fish — freshwater (tilapia, catfish, trout)
- Shellfish (shrimp, crab, lobster, clams, oysters, mussels)
- Mercury
- Methylmercury
- Arsenic, Total
- Cadmium
- Lead
- Chromium
- Copper
- Zinc
- Tin, Inorganic
- Antimony
Verification notes
- Identity check: DOI
10.3390/toxics10100585, raw handleRPMEHG_10-3390-toxics10100585, candidate cite-keywickramaarachchige2022-sri-lanka-aquatic-elements, and SHA-2567b70522aa3955dce324aada87be0f2fce09b81e276afdc181b9f4fd45a91dc72were searched before creation; no existing clean post-2026-05-14 source page was found. - Full-PDF read performed from the 19-page MDPI PDF. Main-PDF Table 1, Figures 1-5, and all main-text numeric summaries were checked once from
pdftotext -layoutand a second time against the extracted layout text before commit. The source’s supplementary Tables S1-S4 are named by the PDF but were not bundled in the local PDF. - Brand firewall: the source reports species- and muscle-level market seafood values, not branded commercial products.
- HMTc firewall: page records source facts only; no certification threshold, percentile, or pass/fail calculation is derived from this source.
Update history
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