Vičarová et al. 2016 — Heavy metals in common carp from three Czech reservoirs
Vičarová and colleagues measured cadmium, lead, and total mercury in the dorsal muscle and liver of 75 common carp (Cyprinus carpio L.), 25 from each of three reservoirs (Pilská, Domaninský, Matějovský) in the Bohemian-Moravian Highlands of the Czech Republic, caught by anglers between April 2013 and September 2014. Cadmium and lead were determined by electrothermal high-resolution continuum-source atomic absorption spectrometry; total mercury by cold-vapour AAS on an AMA 254 analyser. All tissue concentrations are expressed on a fresh-weight basis. Cadmium accumulated preferentially in the liver (means up to 258.1 µg/kg FW at Domaninský), while mercury accumulated preferentially in the dorsal muscle (up to 72.4 µg/kg FW at Domaninský), a tissue-distribution pattern the authors associate with clean rather than heavily contaminated localities. Lead was highest at the Pilská reservoir (muscle 253.3 µg/kg FW, liver 262.7 µg/kg FW), which the authors attribute to legacy traffic-related deposition near a busy road. In all edible muscle samples, cadmium, lead, and mercury complied with the EU maximum limits (Cd 50, Pb 300, Hg 500 µg/kg). The authors conclude that common carp from these reservoirs pose no health risk for human consumption, because the elevated cadmium occurs in liver, which is not commonly eaten.
Key numbers
All fish-tissue values are expressed in µg/kg fresh weight (FW). Table 5 reports means ± SE (the table caption states SE; the Methods section states SD — a reporting inconsistency in the source, noted but not resolvable from the text). Muscle n=25 and liver n=25 per reservoir.
Muscle tissue, mean ± SE (µg/kg FW), Table 5:
- Pilská: Cd 3.6 ± 2.9; Pb 253.3 ± 56.1; tHg 30.6 ± 5.0
- Domaninský: Cd 38.0 ± 21.0; Pb 66.1 ± 29.8; tHg 72.4 ± 19.9
- Matějovský: Cd 0.5 ± 0.1; Pb 13.84 ± 7.500; tHg 18.9 ± 2.0
Liver tissue, mean ± SE (µg/kg FW), Table 5:
- Pilská: Cd 81.0 ± 26.5; Pb 262.7 ± 15.2; tHg 11.5 ± 2.5
- Domaninský: Cd 258.1 ± 47.2; Pb 78.0 ± 33.6; tHg 18.9 ± 7.6
- Matějovský: Cd 49.9 ± 34.0; Pb 14.8 ± 1.9; tHg 8.2 ± 2.0
Tissue-distribution findings:
- Cadmium was statistically higher (P < 0.05) in liver than in muscle, accumulating preferentially in the liver.
- Mercury was statistically higher (P < 0.05) in muscle than in liver, a pattern the authors read as characteristic of clean localities (in heavily contaminated localities Hg deposits preferentially in liver).
- Lead was highest at Pilská in both tissues; no statistically significant muscle-vs-liver lead difference was found at Domaninský or Matějovský.
Sub-group of carp livers with elevated cadmium (50 of the 75 livers), mean ± SE (µg/kg FW):
- Domaninský: 17 samples, Cd 456.0 ± 204.4
- Pilská: 19 samples, Cd 115.0 ± 7.4
- Matějovský: 14 samples, Cd 117.1 ± 1.2
- The authors note carp liver is not intended for human consumption, so these higher values do not pose a consumer health risk.
Reservoir water, mean ± SE (µg/L), n=9 (Table 4):
- Pilská: Cd < LOD; Pb 0.94 ± 0.62; tHg 0.29 ± 0.05
- Domaninský: Cd 0.19 ± 0.06; Pb < LOD; tHg 4.53 ± 0.31 (re-sampled 0.32 ± 0.04 on 20 Oct 2014)
- Matějovský: Cd < LOD; Pb < LOD; tHg 0.15 ± 0.09
- The 4.53 µg/L Hg in Domaninský water (sampled 13 Sep 2014) is flagged by the authors as a likely transient spike linked to recent clearing of the upstream Skalský reservoir; the 20 Oct re-sample (0.32 µg/L) was consistent with the other localities.
Reservoir sediment, mean ± SE (µg/kg dry weight), n=9 (Table 4):
- Pilská: Cd 1.10 ± 0.01; Pb 98.1 ± 3.6; tHg 23.7 ± 1.3
- Domaninský: Cd 2.38 ± 0.13; Pb 14.3 ± 1.0; tHg 13.0 ± 4.4 (re-sampled 12.5 ± 1.2 on 20 Oct 2014)
- Matějovský: Cd 0.95 ± 0.03; Pb 6.25 ± 0.56; tHg 12.0 ± 2.5
Regulatory comparison (EC maximum limits cited by the authors):
- Cd 0.05 mg/kg (50 µg/kg), Pb 0.30 mg/kg (300 µg/kg), Hg 0.50 mg/kg (500 µg/kg) fish and fishery products, per EC Reg. 629/2008 and EC Reg. 1005/2015.
- All edible muscle Cd, Pb, and Hg values were below these limits in every reservoir.
Method validation, DORM-4 reference material (fish protein), mean ± SD, mg/kg dry weight, n=5 (Table 2):
- Cd: certified 0.306 ± 0.015, found 0.304 ± 0.012
- Pb: certified 0.416 ± 0.053, found 0.415 ± 0.025
- Hg: certified 0.410 ± 0.055, found 0.408 ± 0.018
Detection limits (FW):
- Cd: 0.51 µg/kg (muscle), 0.62 µg/kg (liver); 1.09 µg/L (sediment), 0.02 µg/L (water)
- Pb: 4.93 µg/kg (muscle; the liver detection limit is garbled/omitted in the source text); 19.1 µg/L (sediment), 0.38 µg/L (water)
- tHg: 0.11 µg/kg for muscle, liver, water, and sediment
Fish size (Table 3, mean ± SD): weights 2.4–2.5 kg, lengths 47.2–48.2 cm across the three reservoirs; metal content did not significantly differ within the studied weight/length range.
Note: mercury is reported as total mercury (tHg) by thermal-decomposition cold-vapour AAS; no methylmercury speciation was performed. The Discussion references methylmercury qualitatively for heavily contaminated localities elsewhere in the Czech Republic but does not speciate the present samples.
Methods (brief)
Carp dorsal muscle and liver were separated and frozen at −20 °C. For cadmium and lead, samples were lyophilised (Power Dry LL 3000, Thermo Scientific) for 7 days, then microwave-mineralised (0.4 g lyophilised tissue + 8 mL 1:1 nitric acid; Milestone). Cd and Pb were determined by electrothermal high-resolution continuum-source atomic absorption spectrometry (HR-CS AAS, ContrAA 700, Analytik Jena) at 228.8 nm (Cd) and 283.3 nm (Pb), calibrated 0–100 µg/L (Cd) and 0–250 µg/L (Pb). Total mercury was determined by cold-vapour AAS on an AMA 254 analyser (Altec Praha) at 253.7 nm, with direct combustion of solid tissue (100 ± 0.1 mg) at 550 °C and amalgamation trapping; no chemical digestion. Concentrations were expressed in fresh weight (FW). Method validation used certified reference material DORM-4 (fish protein, NRC Canada). Statistics: one-way ANOVA with Tukey’s HSD and paired t-tests (muscle vs liver), significance P ≤ 0.05, software Statistica.cz v10. Reservoir water (filtered 0.45 µm) and air-dried sediment were sampled 13 September 2014 (Domaninský re-sampled 20 October 2014) and analysed by the same instruments.
Implications
Certification: provides total-Hg, Cd, and Pb occurrence data on a fresh-weight basis for wild-caught freshwater common carp muscle and liver from three Czech reservoirs, with paired water and sediment context. Edible muscle complied with EU maximum limits for all three analytes at all three localities; cadmium enrichment was confined to the (non-consumed) liver. Useful provenance and tissue-compartment data for freshwater-fish contamination profiles.
Courses: illustrates analyte-specific tissue partitioning in freshwater fish — cadmium concentrating in liver, mercury concentrating in muscle — and the use of the muscle-vs-liver mercury ratio as an indicator of localised contamination intensity. Also shows legacy traffic-related lead deposition (Pilská reservoir near a busy road) as a non-point contamination source.
App: Cd, Pb, and tHg muscle data (fresh weight) for wild freshwater common carp from Czech Republic reservoirs contribute to species- and product-level contamination profiles; liver values are reported separately and reflect an organ not typically consumed.
Wiki pages updated on ingest
Verification notes
Fresh-context audit subagent (2026-05-30) verdict PROMOTE; all five checks clean.
- Check 1 (numerical fidelity): confirmed exact against the PDF for all six muscle/liver rows of Table 5, both Table 4 matrices (water + sediment, including the 20 Oct re-samples), the 50-liver high-Cd sub-group, Table 2 DORM-4 validation, and the detection limits. No muscle/liver transposition; Cd-in-liver vs Hg-in-muscle direction correctly matched per reservoir. The source’s idiosyncratic “13.84 ± 7.500” Pb formatting and the omitted Pb-liver detection limit are both faithfully preserved/flagged rather than silently fixed.
- Check 2 (slug vocabulary): audit raised a ⚠️ that matrices
fish-muscle/fish-livercannot be confirmed against the taxonomy snapshot. Verified independently — the snapshot has no closed matrices list, andfish-muscle(39 source pages) andfish-liver(11 source pages) are established corpus matrices values used on sibling freshwater-fish pages (e.g. najem2024, kovacik2024). Non-defect; no change. - Check 3 (speciation/methods): tHg total-mercury convention correct (AMA 254, no MeHg speciation); the qualitative methylmercury mention in the source refers to other Czech localities, not these samples. Methods detail matches the source with no inventions.
- Check 4 (Part 12 brand firewall): clean — no brand attached to contamination values; instrument/vendor/reference-material names fall under the methods-vendor exception.
- Check 5 (Part 2 wiki/HMTc firewall): clean — no synthesis, no threshold proposals; consumer/risk statements are the authors’ own attributed conclusions.
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.
| Commit | Date | Description |
|---|---|---|
| ddfd414 | 2026-05-30 | ingest: yildirim2021-humic-fulvic-cd-garden-cress fresh from manual-fetch/seasonal-geographic-variance/auto-fetched |