Studying living things can prove to be highly significant when evaluating contamination suffered by a specific environment. A research team from the University of the Basque Country (UPV/EHU), with Dr. Nestor Etxebarria as director, is involved in this monitoring of contaminants.
As Dr. Etxebarria explains, “it is known that ports are contaminated; what we are investigating is to what extent the contaminants therein reach aquatic organisms”. The project, Comprehensive evaluation of contamination in sediments at ports along the northern Spanish coast, using chemical, biochemical and ecotoxicological tools, is within the remit of the lines of research by the Analytical Research and Innovation (IBEA) research team led by Professor Juan Manuel Madariaga, and aided by doctors Alberto de Diego, Gorka Arana, Aresatz Usobiaga and Olatz Zuloaga.
Biomonitoring of metals and organic substances
Chemists at UPV/EHU, working together with a team of marine biologists from the University of Vigo and a similar team from AZTI-Tecnalia, have been analysing the harbours at this Galician city, as well as those in Bilbao and the port of Pasajes: their waters, the sediments and living creatures therein. They measure the concentration of contaminants and analyse the biological consequences that these cause in the aquatic organisms, using biomonitoring.
“We take mussels from clean waters and place them at points we wish to analyse in order to see how much and what kind of contamination is accumulated”, stated Dr Etxebarria. “The Galician biologists are in charge of studying the consequences of the contaminants on the mussels; we measure the concentration of the contaminants received by the mussels”, he added.
The object of the research is to answer questions such as: where is each kind of contamination located? What is the chemical origin of each? Of all the contaminants, the UPV/EHU team have only managed to analyse a few, amongst which is tributyltin (TBT) metal, used in the past for painting the hulls of vessels. “Today TBT is banned but it is highly durable and it can still be found in waters”, stated Dr Etxebarria. Organic substances have also been studied, such as polyaromatic carbohydrates (PAH) from ships fuel, the phtalates used in making plastics or the polychloride biphenyls (PCBs) derived from oils. “These last are similar to dioxines and in the past were used in very powerful transformers. They are also prohibited, but are still present in the water”, said Dr. Etxebarria.
Biological and chemical sampling
Each year Vigo, Bilbao and Pasajes are visited and simples are taken over two or three days. Five or six zones at each port are analysed, one of which is believed to be clean, i.e. as a control, and the other four or five contaminated. “We place 20 or 30 mussels mounted on plastic supports and inside gauzes, and submerge them at a depth of two metres”, explained Dr. Etxebarria, “after a certain period, we collect them for analysis of level and type of contamination accumulated”.
But using living beings to measure contamination also has its risks. “In some cases the contamination is high and the mussels can die”, states Dr Etxebarria. This is why the UPV/EHU team has created a new method for monitoring contaminants: “by using polymeric mountings, we simulate chemically what the mussels do, i.e. accumulate contaminants”. Moreover, in this way, it is possible to systemise the sampling.
Evaluation of the tools
The research led by Nestor Etxebarria is to finish in 2009, but they already have some provisional results. “The situation in the port of Bilbao is quite homogenous; we have taken samples in the areas of Getxo, Santurce and the exterior port (Bilbao, in the Basque Country) and the results are similar in each case. On the other hand, in Vigo (Galicia) we detected wide differences from one zone to another, for example between water near a shipyard and the open sea”, Dr Etxebarria said.
Apart from carrying out a diagnosis of port waters, another aim of the project is to evaluate the methodology and tools of the sampling. The European Directive on water obliges government bodies to monitor contaminants in all canals and along all coasts. “We wish to know if our methodology and the sampling tools that we have developed are useful for this purpose”, said Dr Etxebarria. “On the one hand, we have seen that zones supposedly clean are not as clean as we thought; it is necessary to redefine the selection of these clean zones. On the other, we are also perfecting the tool that chemically simulates the role of the mussels, in order to carry out even more precise sampling”, he concluded.
Garazi Andonegi | alfa
How does the loss of species alter ecosystems?
18.05.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig
Excess diesel emissions bring global health & environmental impacts
16.05.2017 | International Institute for Applied Systems Analysis (IIASA)
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
24.05.2017 | Physics and Astronomy
24.05.2017 | Physics and Astronomy
24.05.2017 | Event News