"We found positive correlations between the levels of some metals in the waters of the Huelva estuary and those in the tissues of gilthead bream (Sparus aurata) and sole (Solea senegalensis)", Mª Dolores Galindo, a professor of Analytical Chemistry at the University of Cadiz and the head of the study published recently in the Journal of Hazardous Materials, tells SINC.
The researchers focused their analysis on the "bioavailabilty" of heavy metals in coastal waters and their impact on commercially important species, such as the two studied. The results showed elevated levels of zinc, copper and lead, both in water and sediment, although the most "available" elements for the fish were zinc, cadmium and copper.
"Numerous laboratory studies have looked at the effects of pollutants on aquatic organisms, but our research observes this phenomenon in the natural environment, in one of the few estuaries in Spain with high levels of metals contamination", says Galindo. The Huelva estuary and the Tinto and Odiel rivers which flow into it are all affected by discharges from industries and historic mining activities locally. The area, in which fishing is forbidden, is globally significant in terms of its levels of heavy metal contamination.
For this reason it is an ideal area for scientists in which to examine the effects of contaminants on the environment. The researchers, who are working on developing environmental quality criteria, studied the levels of copper, cadmium, lead and arsenic on three types of samples – water, sediments and fish tissue.
By using a statistical index (Pearson coefficient), the scientists found a link between the presence of zinc and cadmium in the water and in the tissues of the fish, above all in the gilthead bream, a species that lives in open water. There was a lower correlation in the case of the sole, which tends to be a bottom dweller, although it also contained lead. Zinc and cadmium appeared in the gills and muscles, but above all in the liver, where copper was also detected at high concentrations.
This research forms part of the project "Production and validation of environmental quality criteria in sensitive coastal ecosystems" financed by the former Ministry of Education and Science, and which also includes analysis of the levels of organic pollutants in the Huelva estuary, as well as the "hystopathological" damage to fish caused by this contamination.
The central government of Spain and the regional government of Andalusia have been developing pollution reduction policies for the estuary since 1997. The measures adopted have included waste water treatment, metal retention processes, waste treatment and reduction of discharges.
References: Juan J. Vicente-Martorell, María D. Galindo-Riaño, Manuel García-Vargas, María D. Granado-Castro. "Bioavailability of heavy metals monitoring water, sediments and fish species from a polluted estuary". Journal of Hazardous Materials 162 (2-3): 823-836, 2009.
SINC | EurekAlert!
Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research