A review of common parameters and descriptors used in studies of the impacts of heavy metal pollution on marine macroalgae: identification of knowledge gaps and future needs

Abstract

This study presents a systematic review to assess the main similarities and gaps in efforts to evaluate the impacts of heavy metals on benthic marine seaweeds. A total of 91 studies were compiled, the main parameters (abiotic, biological, ecotoxicological, and heavy metals) and descriptors of which were evaluated by quantitative and qualitative analyses. Our results indicate the importance of diversifying searches by including different languages (i.e. English, Portuguese and Spanish). Most of the studies were field characterizations, with few abiotic parameters and/or seasonality evaluations being employed. In contrast, the assessment of ecotoxicological parameters was highly frequent, which seems incoherent considering the absence of data to support the use of these results in biomonitoring applications. The genera Sargassum, Ulva and Enteromorpha were widely studied worldwide, apart from a small fraction of studies assessing higher levels of biological organization. Moreover, the use of different parameters and descriptors by the evaluated studies precludes making conclusive or reliable comparisons. These findings highlight the importance of greater efforts to construct a concise baseline of knowledge using similar parameters so that global evaluations of the impacts of heavy metals on photosynthetic organisms can be undertaken.

Marine Pollution - Emerging Issues and Challenges

“…Other metals, including Hg, Pb, Cd and Cr are detrimental to marine organisms even at low concentrations. As pollutants, heavy metals have known effects on the physiological and individual performance of seaweeds (Baumann et al, 2009;Costa et al, 2020), invertebrates (Fowles et al, 2018) and invertebrates with knock on effects on fishes Tamburini et al In sheltered locations, heavy metals are particularly hazardous pollutants in the marine environment because they do not degrade and can bioaccumulate through the food chain with potential detrimental effects to human health via consumption of contaminated seafood (Lavoie et al, 2018). Rare earth elements (e.g.…”

Analysis of intra-thallus and temporal variability of trace elements and nitrogen in Fucus vesiculosus: Sampling protocol optimization for biomonitoring

“…Black and Mitchell, 1952), macroalgae have become one of the most commonly used biomonitors of trace elements worldwide (Bonanno and Orlando-Bonaca, 2018;García-Seoane et al, 2018). However, many basic aspects of this monitoring technique have not been fully addressed so far, despite that they can affect the interpretation of the results obtained in biomonitoring studies (Costa et al, 2020;Al-Homaidan et al, 2021). Two important aspects that are frequently overlooked are the variability in the concentrations of pollutants within the thallus of the algae and the temporal variability within a given site.…”