BLUESHARKER – Blue sharks as biomonitors of Atlantic waters through an integrated biomarker assessment

Abstract/Aim
Marine ecosystems are continuously being burdened with xenobiotic contaminants released by human activities, often resulting in a decline of their resources. Long-lived and top predator marine species such as sharks tend to accumulate particularly high levels of environmental contaminants via bioaccumulation and biomagnification processes. Given their susceptibility to pollutant accumulation, their wide distribution and their importance to the ecosystems, sharks are ideal candidates to be used in marine pollution monitoring studies. Thus, BLUESHARKER will focus on the potential of blue sharks (Prionace glauca), one of the most widely distributed and the most frequently caught shark species, to be used as sentinel species for marine pollution monitoring surveys through the development and application of suitable biological biomarkers. This work will focus on linking the tissue contaminant body burdens of sharks (trace elements and persistent organic pollutants in muscle and liver) to their responses at different levels of biological organization: from molecular markers at the gene level, to biochemical parameters at the sub-cellular level related to detoxification, oxidative stress, neuronal function, immune system and energy metabolism, and histological lesions at the tissue/organ level. Moreover, as an ultimate goal, the research team will check if the correlations found between the contaminant levels and the biological responses for the other tissues can be also found in sharks’ blood and/or skin, which would enable the use of such biomarkers in a less-invasive way in marine biomonitoring programs. Ultimately, this research aims to provide a simple and fast way for assessing the physiological state and general fitness of blue sharks, which given their ecological impact as top predators, will indirectly allow inferring about the quality of the oceans. The results of this project will also be of interest to assess potential risks to human health since this shark species is highly used for human consumption. Moreover, by relating the biological responses with contaminant body burden, an improved understanding on the organisms’ mechanisms to cope with different ocean contamination scenarios will be provided, enhancing the development of a biomarker toolbox for biomonitoring marine environments. A team with different expertise is needed to capture such an integrated and multidisciplinary approach and will be assembled with senior, junior and trainee scientists with expertise in environmental toxicology, environmental chemistry, biochemistry, histology, genomics and transcriptomics, statistics and shark biology and ecology. The collaboration of scientists from different areas of expertise will promote the exchange of knowhow and the highest quality standards in the methodologies applied that will help us to achieve our goals and develop a set of tools with the potential to be used beyond the scope of the present project.

Keywords
Sharks; Toxicology; Ocean contamination; Biomarkers

Partners
Vrije Universiteit Amesterdam (Netherlands), IQOG-CSIC Madrid (Spain), Universidad de Extremadura Cáceres (Spain)

Coordinator
MARE-Polytechnic of Leiria: Sara Calçada Novais – sara.novais@ipleiria.pt

Funding
239.773,23 € (MARE-Polytechnic of Leiria)| POCI – Programa Operacional Competitividade e Internacionalização/FCT – Fundação para a Ciência e a Tecnologia // Duration 2018-2021