Overview
Pereira and colleagues reviewed mercury contamination in the Ria de Aveiro coastal lagoon in Portugal, including historical chlor-alkali contamination in Laranjo bay. The occurrence-relevant table summarizes total mercury in macroalgae, benthic fauna, and fish muscle from Laranjo bay, the broader Ria de Aveiro, and nearby Atlantic waters. The source reports total mercury (Hg) only; it does not measure methylmercury.
Key numbers
Table 3 reports mercury contamination in biotic environmental compartments. Macroalgae are reported in µg Hg g−1, dwt; benthic fauna and fish muscle are reported in µg Hg g−1, wwt.
| System | Matrix or species | Source-reported total Hg |
|---|---|---|
| Laranjo | Enteromorpha sp., macroalga | 0.37 ± 0.45 |
| Laranjo | Gracilaria sp., macroalga | 0.34 ± 0.25 |
| Laranjo | Fucus sp., macroalga | 0.47 ± 0.1 |
| Ria | Enteromorpha sp., macroalga | 0.09 ± 0.08 |
| Ria | Gracilaria sp., macroalga | 0.04 ± 0.04 |
| Ria | Fucus sp., macroalga | 0.05 ± 0.04 |
| Laranjo | Scrobicularia plana, benthic fauna | 0.37 ± 0.26 |
| Laranjo | Carcinus maenas, benthic fauna | 0.33 ± 0.17 |
| Ria | Scrobicularia plana, benthic fauna | 0.03 ± 0.01 |
| Ria | Carcinus maenas, benthic fauna | 0.09 ± 0.01 |
| Ria nearshore | Donax vittatus, benthic fauna | 0.0085 ± 0.0006 |
| Ria nearshore | Spisula solida, benthic fauna | 0.014 ± 0.005 |
| Laranjo | Dicentrarchus labrax, fish muscle | Range 0.03-1.7 |
| Ria | Dicentrarchus labrax, fish muscle | Occasionally >0.5 |
| Ria nearshore | Echiichthys vipera, fish muscle | 0.085 ± 0.026 |
| Ria nearshore | Trigla lucerna, fish muscle | 0.043 ± 0.012 |
| Ria nearshore | Dicologlossa cuneata, fish muscle | 0.12 ± 0.04 |
The abstract states that macrophyte harvesting for human direct or indirect use and consumption of mussels, crabs, and sea bass from Laranjo bay may constitute a health risk. The discussion notes that all studied biota species showed higher mercury contamination in Laranjo bay than in the broader Ria de Aveiro and nearshore areas. Salt-marsh plant values also appear in Table 3, but they are not routed here as food-product occurrence values.
Methods (brief)
The paper is a review of several Ria de Aveiro studies rather than a new sampling campaign. It collates abiotic and biotic mercury findings from water, sediments, suspended particulate matter, macroalgae, salt-marsh plants, benthic fauna, fish muscle, and nearby terrestrial soils. The occurrence table cites underlying studies by Coelho et al., Pereira et al., Pato et al., and Abreu et al.; the page records the review table as secondary evidence and leaves primary-study extraction to source-specific ingests where those papers are available.
Implications
This source supplies Portugal-specific total-mercury context for seafood, shellfish, fish, and edible/harvested macroalgae near a historically contaminated chlor-alkali system. It is useful for routing broad Ria de Aveiro evidence but should not be used as methylmercury evidence and should not be treated as a primary market survey. Downstream use should keep dry-weight macroalgae values separate from wet-weight shellfish and fish-muscle values.
Update history
The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git.
| Commit | Date | Change | Description |
|---|---|---|---|
| b01ec52c31 | 2026-08-04 | major | 1 section added |
| 3171d069e3 | 2026-08-02 | major | 1 section added |
| 90a2f9a38e | 2026-07-30 | major | 1 section added and 1 removed |
| eaa8eeeedf | 2026-07-27 | major | 1 section added and 1 removed |
| aca5e2155a | 2026-06-09 | major | 1 section added |
