A multibiomarker approach in Mytilus galloprovincialis to assess environmental quality

Abstract

A multibiomarker approach was carried out for the first time in the South Portuguese Coast using Mytilus galloprovincialis, to assess environmental quality, establish if there are adverse biological responses associated to different sources of anthropogenic contamination and to determine spatial and seasonal trends. For this purpose the battery of biomarkers selected was: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx total and Se dependent), Cytochrome P450 component system, Glutathione-S-transferase (GST) and acetylcholinesterase (AChE), metallothionein (MT) and lead-delta-aminolevulinic acid dehydratase (ALAD), lipid peroxidation (LPO) and Condition Index (CI) along with the determination of PAHs and metals (Cd, Cu, Ni, Pb and Zn). Results show that despite the levels of both organic and metallic contaminants in these eight spots in the South Coast of Portugal not being particularly high compared with other contaminated/polluted sites worldwide, the selected battery of biomarkers responded efficiently to the environmental changes and allowed an environmental assessment between seasons and sites. Different spatial and seasonal responses were evident along the South Coast of Portugal, meaning that the contamination is not homogeneous. This does not only reflect different competition, origin and intensity of contamination, but also different environmental conditions (e.g. temperature, salinity). Along the South Portuguese Coast site 8 was the most contaminated, while site 2 was considered the least contaminated. Despite environmental factors possibly causing difficulties in the general interpretation of biomarker data, those that better responded to environmental contamination were CYP450, SOD-mit and T-GPx for the summation SigmaPAHs, MT (digestive gland) for metals (especially Cu), ALAD for Pb and LPO for both organic and metallic contamination. These biomarkers were also positively correlated with temperature in summer, revealing this as a more stressful/critical season. In future environmental contamination assessments there is no need to analyse the components b5, P418, NADH and NADPH of phase I MFO system, and MT in the gills, since their responses are not evident.

A multibiomarker approach in the clam Ruditapes decussatus to assess the impact of pollution in the Ria Formosa lagoon, South Coast of Portugal

“…The present study was undertaken at the middle region of the lagoon, in the most important shellfish bed area within this ecosystem, which accommodates one the major fishing harbours in the South Coast of Portugal. This area is known to be affected by contaminants due to intensive boat traffic and magnitude of fish products in an area of reduced hydrodynamic conditions (Bebianno et al, 2007;Coelho et al, 2002;Cravo et al, 2009;Maria et al, 2009). …”

“…Highly productive areas such as estuaries and coastal lagoons are among the most extensively modified and threatened ecosystems mainly due to urban develop--ment, industrialization and tourism. As a result, complex mixtures of contaminants are continuously released to these systems deterio--rating the water quality and imposing severe restrictions to organ--isms and possibly causing a decrease in natural resources (Cajaraville et al, 2000;Cravo et al, 2009;Monserrat et al, 2007). Such an example is the Ria Formosa lagoon, a major coastal lagoon in the Portuguese south coast particularly important for tourism and fish--eries, especially shellfish (Bebianno et al, 2007).…”

“…Such an example is the Ria Formosa lagoon, a major coastal lagoon in the Portuguese south coast particularly important for tourism and fish--eries, especially shellfish (Bebianno et al, 2007). The contaminants already known to be present in water, sediments and biota from specific sites of the lagoon include metals (Bebianno, 1995;Bebianno andSerafim, 1998, 2003;Caetano et al, 2002;Cravo et al, 2009;Serafim and Bebianno, 2001), polycyclic aromatic hydrocarbons (PAHs) (Barreira et al, 2007a, b;Bebianno et al, 2007;Bebianno and Barreira, 2009;Cravo et al, 2009), polychlorinated biphenyls (PCBs) (Barreira et al, 2005;Bebianno et al, 2007) and organotin compounds (Coelho et al, 2002;Díez et al, 2005).…”

“…Field studies that include a multibiomarker approach allow measurements of the impact of several environ--mental stressors. This approach has been very successful with invertebrates and nowadays it is a recommended tool for envi--ronmental monitoring programs (Bebianno et al, 2004;Cravo et al, 2009;Maria et al, 2009;Porte et al, 2001;Viarengo et al, 2007). Therefore, the aim of this study was to apply a suite of biomarkers in an attempt to understand the time and space contamination trend within this ecosystem and its potential adverse effect on clams.…”

“…The use of a battery of different biomarkers enables the assess--ment of a variety of responses but it does not completely replace the chemical approach (Bebianno et al, 2004;Cravo et al, 2009). There--fore, in this study selected contaminants were also analyzed in clams tissues: metals (cadmium, copper, nickel, lead, zinc), Tributyltin (TBT) and PAHs (mostly associated with boat traffic).…”