Measurement / residue studyindependent cross-checkabstract checked I-FSH-106 standard review
Metals in sea fish from Damietta, Egypt
Health hazard assessment and cooking effects on toxic metals in marine fish from the mediterranean sea at the Damietta Coast, Egypt.
Overview
Makroum AH et al.. Sci Rep 2026 · PMID 41526512 · DOI 10.1038/s41598-025-33257-3
Lead and total arsenic were above limits in many samples; mercury was within limits.
Does the study support the specific claim? Partly · Methodological quality: low
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Measure metals in local sea fish.
- How was the study done?
Chemical analysis of 240 fish.
- How many people, animals or samples were studied?
Mullet, sardine, sand smelt.
- What was actually found?
Arsenic and lead concerns; mercury low.
- How large was the observed effect?
See results.
- What do the results mean in everyday life?
Sea fish from polluted coasts can contain lead.
- What are the study's limitations?
Total arsenic overstates risk.
- What does it say about Elawady's specific claim?
Sea fish is not automatically clean.
- Do the results apply to Germany and Europe?
Low.
- What can explicitly not be concluded from this study?
National representativeness.
Scientific in-depth review
1. Full reference
- Authors
- Makroum AH et al.
- Journal
- Sci Rep
- Year
- 2026
- Identifier
- PMID 41526512 DOI 10.1038/s41598-025-33257-3
- Verification
- verified – PubMed efetch 2026-10-26; Crossref checked
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
Authors declare no competing interests
2. Research question
Toxic metals in marine fish from the Damietta coast and the effect of cooking
3. Study design and population
- Study design
- Measurement / residue study – Exposure measurement and health risk assessment
- Population
Thinlip grey mullet, sardine, sand smelt
- Country
Egypt
- Period
not stated in abstract
- Sample size
240 fish (80 per species)
4. Methods and endpoints
- Exposure / intervention
As, Hg, Pb, Cd
- Comparator
Permissible limits
- Endpoints
Concentrations, THQ, cancer risk
- Statistical methods
Means ± SE; THQ; cancer risk
5. Actual results
- Results
Mean (mg/kg) As/Hg/Pb/Cd: mullet 2.29/0.119/0.651/0.042; sardine 1.68/0.098/1.011/0.049; sand smelt 1.87/0.055/0.965/0.052. '100% of fish samples exceeded the permissible limit for As, while Hg levels were within the safe limits for all tested samples.' THQ exceeded limits for As and Pb; arsenic cancer risk exceeded the threshold. Frying and grilling reduced metal levels.
- Absolute risks
not reported
- Authors' conclusion
Strict control of arsenic and lead contamination is needed.
6. Strengths
- Egyptian marine fish
- Reasonable sample size
7. Weaknesses
- Total arsenic used; most arsenic in marine fish is non-toxic arsenobetaine, so arsenic risk is probably overestimated
- Single coastal area; wild or farmed origin of mullet not stated in the abstract
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- some concerns
- Rationale
Total-arsenic risk calculation.
9. Assessment of the statistical interpretation
10. Relevance to the specific claim
C-FSH-14: Egyptian coastal sea fish are not automatically 'clean' (lead); mercury was within limits in these small species.
11. Independent contrary findings
12. Transferability to Germany and Europe
Low.
13. Overall methodological judgement
Egypt-specific evidence that coastal sea fish can carry lead; mercury low in small species.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | low |
| Risk of bias | some concerns |
| Precision of results | moderate |
| Directness | direct |
| Reproducibility | partly replicated |
| Consistency with the overall evidence | mixed |
| Regional transferability | high |
| Adequacy of the interpretation (by the archive) | not applicable |