1 research outputs found
Assessment of mercury and methylmercury pollution with zebra mussel (Dreissena polymorpha) in the Ebro River (NE Spain) impacted by industrial hazardous dumps
7 páginas,3 figuras, 2 tablas.Large amounts of industrial waste containing high concentrations of mercury (up to 436 μg/g)
are dumped in a reservoir adjacent to a chlor-alkali plant in Flix (Catalonia, Spain), on the
lower Ebro River. In order to assess the spatial redistribution of mercury from the point
source and its bioavailability to the aquatic food web, zebra mussels (Dreissena polymorpha)
were collected at several sites. The highest total Hg (THg) and methylmercury (MeHg)
concentrations ever reported for zebra mussels were found (THg: 0.02 to 0.81 ÎĽg/g ww; MeHg:
0.22 to 0.60 ÎĽg/g ww). At the most polluted site, close to the waste dump, the mean values
were 20 times greater than the local background level. Concentrations decreased with
increasing mussel size at all sites. The MeHg/THg ratio was ca. 60% (range: 50–80%). A
comparison of similar size classes clearly indicated the hot spots of Hg bioavailability to the
aquatic food web and downstream transport.Financial support was obtained from the Spanish Ministry of
EnvironmentandtheACA(GeneralitatdeCatalunya). L.Carrasco
acknowledges the Consejo Superior de Investigaciones CientĂficas for
an I3P fellowship. S. DĂez would like to express his gratitude for
the financial support of the MCyT through the RamĂłn y Cajal
program.Peer reviewe