Regoli, F., D. Pellegrini, A.M. Cicero, M. Nigro, M. Bededetti, S. Gorbi, D. Fattorini, G. D’Errico, M. Di Carlo, A. Nardi, A. Gaion, A. Scuderi, S. Giuliani, G. Romanelli, D. Berto, D. Trabucco, P. Guidi, M. Bernardeschi, V. Scarcelli, G. Frenzilli (2014) A multidisciplinary weight of evidence approach for environmental risk assessment at the Costa Concordia wreck: Integrative indices from Mussel Watch, Marine Environmental Research v(96), pg. 92-104, http://dx.doi.org/10.1016/j.marenvres.2013.09.016.
Headlining international news on January 13, 2012 was the devastating grounding of the Costa Concordia cruise ship on a submerged rock near the entrance of Giglio Harbor, Giglio Island, Tuscany, Italy (Figure 1). Unfortunate events like this require immediate response to potential environmental impacts, both immediate and long term, as a result of chemicals entering the water column and sediment. Assessing a wreckage site is complicated due to the unknown nature of released chemicals and the complexity in which they interact with the environment. Investigations led by the National Civil Protection and the Italian Institute for Environmental Protection and Research (ISPRA) focused on the biological and chemical oceanographic approaches for monitoring of the water column and sediment. Information from various studies is entered into a complicated algorithm called Sediqualsoft designed to weight the value of different results to produce an overall environmental evaluation surrounding the wreckage site.
The research focused on in Regoli et al. (2014) is the Mussel Watch. Mussel Watch is a year-long investigation of caged Mytilus galloprovinciali focused on the early detection of toxicological effects of anthropogenic pollutants that may have been released into the marine environment as a result of the wreck. Mytilus galloprovinciali are used because there are no native populations in that area, essentially making the mussels a control organism. In previous works, Mytilus galloprovinciali have proven to adapt easily to varying environmental conditions (i.e. changes in organic and inorganic pollutant concentrations), and the reactions of the molecular and cellular systems to these changes are preserved in such a way that a time-integrated analysis can be accomplished. During the year the experiments were performed, both the emergency phase (oil and fuel removal) and part of the “Parbuckling project” (an effort to refloat and tow away the wreck, completed July 23, 2014) were occurring, potentially introducing multiple pollutants to the environment that are also important to monitor. Some of the pollutants analyzed in the tissues of the mussels include: trace metals, polycyclic aromatic hydrocarbons (PAH’s), volatile and aliphatic hydrocarbons (C6-C10 and C10-C40), polychlorinated biphenyls (PCBs), organo-chlorinated pesticides (OCPs), and brominated flame retardants (BFRs).
Mussels used in this research were taken from 8 meters of water at Caldane (the reference site) and transplanted to the wreck site, Giglio Porto, and the reference site (Figure 2) for seven 4-6 weeks periods at two depths (1.5 m below sea surface and 1.5 m above bottom) between February and December 2012. At the conclusion of a translocation period samples were collected from each site and depth and were frozen at subzero temperatures for chemical analysis. Analysis of tissues included gas-chromatography, high performance liquid chromatography (HPLC), inductively coupled plasma (ICP), and atomic absorption spectrophotometry (AAS), among others. Analysis of variance (ANOVA) was applied to compare the statistical significance of results from the three sites and two depths
Analyses of tissues in mussels were completed with a multiple biomarker approach. Basically this means scientists look a specific components of the cell to detect if it is responding in an abnormal way to changing conditions. For example, peroxisomes play an essential role in fat break down for energy use. When peroxisomes are exposed to organic xenobiotics the mussels response by increasing the number and volume of organelles, so scientists can use an increased organelle concentration to identify the impact of xenobiotics. In addition to perioxisomes, scientists also look at metallothioneins which are involved in homeostasis of essential metals and are more active when exposed to increased concentrations of metals.
Chemical toxicity is traced by enhanced generation of reactive oxygen species inside a cell. It can also be recognized from the response of lysosomal systems. Lysosomal systems are the organelles involved in basic cell function, food digestion, immune function, and removal of harmful compounds; toxicity affects the membrane stability of the systems. Lastly, toxins resulting in mutation of genetics are accessed from breaks in DNA strands.
All in all the wreck did not have immediate alarming impacts on the mussels studied. In summary, it was determined that many of the measured statistically significant bioaccumulated increases were correlated with recovery efforts and increased anthropogenic activity. The wreck itself did not release much pollution: trace metal results show a statistically significant increase that is prominent in the shallow cages but does not have a time dependent trend; xenobiotics had an irregular variation; and PCB’s, halogenated pesticides, and BFRs were not significantly measured for any site or depth (Figure 3). Furthermore, many changes observed can be attributed to factors like temperature, reproductive maturation, and nutrient availability.
Results of early detection studies like this one can be used to monitor potentially serious contamination events from wrecks and monitor the degree of pollution from emergency response efforts. By monitoring change in increments of time, a snapshot of when the most significant impacts occurred can be captured to increase the likelihood of identifying the cause.
Results from studies like Regoli et al. are incorporated into a Sediqualsoft model. The Sediqualsoft model uses logical flowcharts and mathematical algorithms to classify sediment quality and to judge environmental hazards in coastal areas for which there are multidisciplinary studies involved. The information from Mussel Watch will be mixed with results from studies involving native fish and invertebrates, water column and sediment chemistry, and benthic community changes, to try and give reliable information about the environment surrounding the Costa Concordia wreck.
Hello, welcome to Oceanbites! My name is Annie, I’m a marine research scientist who has been lucky to have had many roles in my neophyte career, including graduate student, laboratory technician, research associate, and adjunct faculty. Research topics I’ve been involved with are paleoceanographic nutrient cycling, lake and marine geochemistry, biological oceanography, and exploration. My favorite job as a scientist is working in the laboratory and the field because I love interacting with my research! Some of my favorite field memories are diving 3000-m in ALVIN in 2014, getting to drive Jason while he was on the seafloor in 2017, and learning how to generate high resolution bathymetric maps during a hydrographic field course in 2019!