Preliminary results of beluga whale skin analysis

Preliminary results of beluga whale skin analysis

13 August 2013

Genetic analysis and organic contamination tests have been carried out on tissue samples from beluga whales off the Solovki Islands breeding grounds in the Onega Bay of the White Sea.


In the summer 2011, the participants of the expedition ―Beluga Whale of the White Sea Shirshov Institute of  Oceanology, 4 samples of the beluga whale of the Solovetskie breeding aggregation were collected. Three samples were collected, using a crossbow off Cape Beluzhy and one was collected from a dead beluga whale stranded off Cape Pechak in the south of Solovetsky Island. Genetic test and test for organic contamination of the obtained beluga whale tissues were performed with financial support provided by the International Fund for Animal Welfare (IFAW) and with assistance provided by the Marine Mammal Council.


The genetic test of the samples collected was per-formed in A.N. Severtsov Institute of Ecology and Evolution, RAS. Full-fledged results were obtained only for three tissue samples collected with a crossbow. The fourth sample collected from the stranded carcass were in a decomposed condition owing to which it was pos-sible to obtain from it only mitochondrial DNA. It was revealed that all the three animals from Cape Beluzhy had the same mitochondrial haplotype that is the most widespread (85%) and in the beluga whale samples from the mouth of the Varzuga River (the Kandalaksha Bay of the White Sea) captured by the researchers from A.N. Severtsov Institute in the October, 2011. Microsatellite analysis revealed that neither comparison of 3 (Cape Beluzhy) and 8 (Varzuga Riverа) for 19 nor 3 (Cape Beluzhy) or 12 (Varzuga River) for 9 loci any differences were found. Thus, tentative conclusion (owing to small samples) is that no genetic differences between July beluga whales of the Solovetskie breeding aggregations and October ones from the Varzuga River. Presumably, all the animals belong to the same population (genetic commonness), represented by a single set of mother lines. It is noteworthy that all the beluga whales captured in the mouth of the Varzuga River were males.


The test for organic pollution of the tissues was per-formed in the Federal State Budget Enterprise «Re-search and Production Association ―Typhoon, Chemical Analytical Center of the Federal Service for Hydrometeorology and Monitoring of the Environment of the city of Obninsk. In addition, due to the small mass of the (0.7 cm3) tests were made for the content of only three classes of compounds, biphenyls and toxaphenes. In addition, due to the small mass of the samples collected by means of the crossbow, the results of the tests may be not correct enough for limited sensitivity of the analytical equipment (those samples mainly contain the cellular tissue of the skin and a small percentage of lipids). A reliable sample the results of the test of which could be considered are the tissues collected from a beluga whale carcass stranded off Cape Pechak.


According to the specialists who performed that work, the pollution of the tissues with persistent organic pollutants (POP) for the sample collected from the beluga carcass is anomalously high. Some high levels of bi-phenyl content were found. Polychlorynated biphenyls (PChB) are the product of a largecapacity chemical production were widely used in the 1950s-70s inlargescale units as transformers, condensers. The presence of high concentrations of PChB in beluga whale tissues can be accounted for by getting the industrial effluents of the city of Severodvinsk and the city of Arkhangelsk into the closed water area of the White Sea.


Of interest is shown by the sample from the dead beluga whale is the level of pollution with brominated anti-pyrenes. This is a relatively new compound used in the manufacture of plastics. A high concentration of lipophilic POP should be noted, which are very poorly extracted from the body, and with age are accumulated in the animal body.


Availability of notable amount of mirex and number of chlordane is also found. Chlordane is toxic to fish, birds, and in humans they affect the immune system and are potential carcinogens. Mirex is not toxic to humans but is a potential carcinogen. Pesticides, which include mirex and chlordane are normally specific and are used against certain types of pests. In particular, include mirex and chlordane are normally specific and are used against certain types of pests. In particular, mirex and some chlordanes are special agents to control ants and termites. In the USSR and RF those agents were not manufactured and their application on the White Sea coast or their bringing out with the rivers from the European part is out of the question. Mirex and chlordanes were used actively in India and South China. Those compounds being clearly identified in the represented sample, their appearance may be accounted for by their global transfer from the South-Eastern Asia.


It should be taken into account that the content of POP in the tissues is also dependent on the sex of the animal. Normally after parturition and nursing, the content of POP in the female tissues sharply decreases, which should be taken into account in assessing the level of pollution. In addition, the age of the animal should be determined.


The presented findings are only tentative, the sample being small. It is necessary to continue studies in the White Sea.