In November 2012, upon being Talvivaara adjacent waters in fish tissue was observed only minor changes in the gills. Food Safety Authority Evira made initial inquiries showed no significant heavy metals or minerals deposits.
Tissue studies were sought information on research water roach, perch and mateiden, in the alternative, for other species of fish gills, liver and kidney condition. Acute tissue damage signs that tell of, inter alia, the acidic water and heavy metals from damage, was not found. Stone River särjillä found kidusepiteelin hypertrophy, which is probably a result of infestations. Certainly can not be ruled out due to leakage in the Talvivaara irritation partly due to overgrowth.
Fish meat were 83 samples were studied heavy metals, arsenic, mercury, cadmium, chromium, lead, nickel and uranium. For the same samples were analyzed for trace elements in aluminum, copper, manganese and selenium. The analyzes did not reveal background values in excess concentrations. In preliminary analyzes of bone was observed accumulation of uranium in the spine.
In the general area of the species of fish
The compared species common in the area. The roach is known to be more sensitive to changes in the acidity of the water and burbot. Talvivaara mine waters below the waste water has been found to arise from the deeper reaches, therefore, is made in the study as a typical pohjakalana.
Natural Fish may avoid adverse conditions for themselves, so the fish will be purchased by the fish does not necessarily say the changes caused by pollution. On the other hand research area for swimming fish pristine areas. Now the analyzed fish produce, however, the background material, which was later carried out sampling of tissue changes and heavy metal concentrations in long-term changes can be compared.
Since the accumulation of metals in fish is slow, the results are expected. Any deposits and tissue damage monitoring will continue.
This stage of research Evira considers that the Kainuu ELY Centre in November 2012 issued by the Talvivaara surrounding water bodies to use the recommendations of refinements drinking water and recreational use, as well as eating fish is still a need to follow.
Continue the exploratory fisheries
Finnish Game and Fisheries Research Institute (Novo) was carried out in exploratory fisheries in the Talvivaara mine waste water affected 15 to 27/11/2012 Food Safety Authority Evira and Kainuu ELY Centre in collaboration with the research plan accordingly.
EXPLORATORY were Oulujoki the side of the Rock River, Rock Lake, and Kolmisoppi Jormasjärvi Vuoksi, as well as the side of Stone River, Stone Lake and Flat Lake. In addition, a possible leak caught outside the Oulu River basin Kivesjärvessä, Paltamo.
RKTL has launched a sampling plan, a new koekalastuskierroksen in January 2013 for chemical analysis. Verkkokoekalastukset subjected to the same areas as the lake in November 2012. In addition, fish samples collected from the reference areas, which are not water of impact. The third round of sampling is planned for the open water season and the samples studied both histologically and chemically.
