Baseline Trace Metals in Seagrass, Algae, and Mollusks in a Southern Tyrrhenian Ecosystem (Linosa Island, Sicily)

Abstract

Trace elements were analyzed in organisms collected at five sampling stations along coastal areas of Linosa Island, Sicily (southern Tyrrhenian Sea, Italy). Concentrations of Cd, Cr, Cu, Pb, and Zn were measured in Posidonia oceanica L. Delile tissues, the two brown algae Padina pavonica (L.) Thivy and Cystoseira sp., and the two gastropod mollusks Monodonta turbinata Born and Patella caerulea L. Seawater samples were also collected at each site to assess soluble metal concentrations and to gain relevant information on their bioaccumulation ability. Data were processed by multivariate techniques, such as principal component analysis (PCA) and linear discriminant analysis on PCA factors. The scoreplots obtained showed that the pollutant distribution is more significantly correlated with species than with sites. For seaweeds, P. oceanica was associated with higher Cd, Cu, and Zn levels; Padina species had higher Cr concentrations, and Cystoseira had higher Pb levels. For mollusks, Monodonta species had high concentrations of Cu and Cr and Patella species were associated with Cd. Some general metal bioaccumulation patterns are described but no one sampling site was more contaminated than the others. The hypothesis of Linosa island serving as a reference ecosystem for baseline trace metal levels in southern Tyrrhenian areas is indeed supported by the statistical comparison among other southern Tyrrhenian ecosystems performed with Kruskall Wallis and Mann-Whitney tests. For P. oceanica leaves, P. pavonica, M. turbinata, and P. caerulea, this study confirms their usefulness as possible cosmopolitan biomonitors of trace metals in marine Mediterranean areas.

Chemical contamination along the Mediterranean French coast using Posidonia oceanica (L.) Delile above-ground tissues: a multiple trace element study

“…This sequence completes and confirms the sequence commonly observed in P. oceanica: Zn > Ni > Cu > Cd, Pb > Cr (Pergent-Martini, 1994;Warnau et al, 1995;Schlacher-Hoenlinger and Schlacher, 1998;Campanella et al, 2001;Conti et al, 2010).…”

“…These findings are in agreement with previous studies: PergentMartini (1994) for Cr, Fe, Cu, Zn, Cd and Pb; Campanella et al (2001) for Cr, Zn, Cd and Pb, but not for Cu; Kljakovic-Gaspic et al (2004) for Cd and Pb; Lafabrie et al (2008) for Cr, Co, Ni, Cd and Pb; Conti et al (2010) for Cr, Cu, Zn, Cd and Pb. Assimilation of TEs among rooted aquatic plants occurs through two pathways: uptake by leaves from the water column or by roots from interstitial water.…”

“…For the particular case of Cu, the systematic but quite limited upper level in SAL (as opposed to BAL) could be explained by an increase in metabolic activity during growth, when Cu (an essential micronutrient) is needed, as mentioned by Conti et al (2010). Physiological metrics vary with the tissue age and are influenced by the presence of epiphytes.…”

Metals in molluscs and algae: A north–south Tyrrhenian Sea baseline

“…Recently, gastropod molluscs have contributed to the more complete understanding of bioaccumulation and ingestion by humans in marine Mediterranean areas [11][12][13][14].…”

“…Additionally, bioaccumulation may not be toxic to one (or more) species [1][2][3][4]7,8] but may be an index of human exposure, particularly when the species is known to be indigenous food (e.g., Patella); besides, the selected species have high concentration factors (CFs) and are sedentary, easily identifiable, ubiquitous and can be used as a good biomonitors of baseline seawater trace metal pollution [11][12][13][14].…”