Jun 25, 2019 - Science and innovations
A Discussion on the Concentration of Pesticides in Marine Organisms was Held in FEFU
The concentration of organochlorine pesticides (OCPs) in mussel tissues in the Russian Far East, which were globally used in agriculture in the middle of the 20th century, increased by ten or more times. This was reported by an ecotoxicologist from the Far Eastern Federal University (FEFU), Vasily Tsygankov. The scientist noted that the OCPs penetrate the ecosystems of the Sea of Japan, the Sea of Okhotsk and the Bering Sea. A review article covering the results of research on organochlorine pesticides for 2010–2017 was published in Water Research.

Vasily Tsygankov clarified that, according to new, yet to be published experimental results, the concentration of organochlorine pesticides (OCPs) in Far Eastern mussels decreased by almost three times. Similar fluctuations in pesticide content are also characteristic of other species of marine animals: molluscs, fish, seabirds, and mammals, in whose fatty tissues toxicants are heavily concentrated. Pesticides enter marine organisms from coastal waters, where their concentration may be particularly high.

The presence of OCPs in the environment is a serious danger to all living things that are at the top of the food chain, not only for animals but also for humans, noted the study's author. The reason is that the biomagnification process takes place: pesticides in higher concentrations accumulate among representatives of higher trophic levels as a result of feeding on organisms of lower trophic levels, which contain a low amount of toxicants.

“This can lead to poisoning and even death. It has been established that OCPs suppress the endocrine and immune systems of marine animals, lead to various deviations and genetic changes in the population, and provoke the occurrence of tumours. These are good enough reasons for every one of us to think about new standards for monitoring pesticides in the environment, particularly in the Russian Far East.” said Vasily Tsygankov, assistant professor of food science and technology, head of the eco-biotechnology laboratory at the FEFU School of Biomedicine.

The scientist explained that we are talking about the simultaneous, systematic and ever continuous study of different types of marine animals. Its results will be the basis for conclusions about whether the situation with pesticides is getting better or getting worse. It is possible that different regions will have different pictures.

OCPs are the most persistent organic pollutants. They decompose extremely slowly and therefore easily spread and accumulate in aquatic ecosystems of different parts of the world even many decades after their application. Even at the lowest concentrations, OCPs adversely affect the marine biota, especially zooplankton and crustaceans. Pesticides often accumulate in coastal waters, from where they get into the organisms of molluscs, fishes, seabirds, and mammals, in the fatty tissues in which they are heavily concentrated.

The main sources from which the OCPs enter the environment, the scientist called leaks from storages and warehouses, agricultural fields of countries that continue to use them, atmospheric phenomena, sea currents and the migration of marine animals - for example, Pacific salmon.

Vasily Tsygankov stressed that the spread of toxic OCPs on a global scale was proven by the fact that they were found both in the Arctic and in the Antarctic.

FEFU has been studying the OCPs in the environment of the Far East for nearly 10 years. Previously, FEFU scientists determined that pesticides accumulate in marine organisms with a high content of fat tissue, as well as in marine animals with a longer life cycle.

The study was conducted with the support of the Russian Science Foundation (№18-14-00120).