Micro-nano-sized polytetrafluoroethylene (teflon) particles as a model of plastic pollution detection in living organisms.

Micro- and nano-sized particles of polytetrafluoroethylene (PTFE) were used as model (reference) particles to study the biological effects of plastic pollution. Since the PTFE molecule contains fluorine, considered as an "atomic marker" sharply distinguishing it from other common plastics, micro- and nano-particles of PTFE have a specific crystalline structure and are, therefore, well identified by the methods of polarized light microscopy (POL), Raman microspectroscopy (micro-Raman), and energy-dispersive spectroscopy (EDS). Examples of PTFE particles detection in hemolimph of the cockroach Blatella germanica, in hemolimph of the larva and in faecal pellets of imago of a fly Lucilia sp.

Steller Sea Lion () at Tuleny Island, Russia in Autumn 2018: Abundance, Composition, and Entanglement.

The Steller sea lion (SSL, ) inhabits the North Pacific Ocean off both the North American and Asian coasts. The abundance of the species in Asia declined by more than half in the second part of the 20th century. Decline recurred in the second decade of the 21th century after a short period of restoration.

Analysis of essential and non-essential trace elements in the organs of a mother-fetus pair of spotted seals (Phoca largha) from the Sea of Japan.

Concentrations of 22 essential and non-essential trace elements (Be, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sb, Ba, Tl, Pb, Th, U, and Hg) were measured in the organs of a mother-fetus pair (at the last trimester of pregnancy) of spotted seals from the Sea of ​Japan. The concentrations of eleven elements are reported for the first time. Eight organs of the pair were examined: lungs, heart, liver, kidneys, intestines, spleen, muscles, and bones.

Antioxidant activity of Far Eastern bivalves in their natural habitat.

The activities of the key antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GP) and glutathione reductase (GR) as well as levels of reduced glutathione (GSH) and integral antioxidant activity (IAA), were studied in the digestive glands and gills of 14 bivalve species. Species and tissue differences of the antioxidant (AO) systems of the investigated mollusks were discussed in connection with their physiological and biochemical peculiarities. This article describes the role of the AO system of mollusks in adaptation to natural habitat conditions and shows the relationship of AO activity with the maximum habitat depth (MHD) and maximum lifespan (MLS) of these species.

Assessment of mercury levels in modern sediments of the East Siberian Sea.

Mercury (Hg) is an important environmental indicator of anthropogenic pollution. In this study, the Hg content in the bottom sediments of the East Siberian Sea was observed to range from 13 to 92 ppb, with an average of 36 ppb. Facies dependence was also observed and expressed as an increase in the Hg concentration in fine-sized sediments on the shelf edge and continental slope, compared to that in the sandy silts and sands of the inner shelf.

Quantitative study of the behavior of two broadcast spawners, the sea urchins and , during mass spawning events in situ.

Background: The spatial distribution of spawners and temporal parameters of spawning in motile invertebrates with external fertilization might influence reproductive success. However, to date, data on the prespawning and spawning behaviors of broadcast spawners in the field have been scarce and mostly qualitative. The present study was intended to clarify the behavioral adaptations of two sea urchin species, and , using quantitative analysis of their behavior during mass spawning events under natural conditions.

Tumor-Associated Macrophages as Potential Targets for Anti-Cancer Activity of Marine Invertebrate-Derived Compounds.

Tumor-associated macrophages (TAMs) are M2 phenotype dominant and promote tumor growth and metastasis. The new cancer treatment strategy includes TAM targeting and is aimed primarily at reprogramming TAMs toward the M1 phenotype or reducing the number and activity of M2 macrophages. Several marine invertebrate-derived drugs, combining efficacy and a low level of side effects, were approved for use in the cancer therapy.

Distribution of floating marine macro-litter in relation to oceanographic characteristics in the Russian Arctic Seas.

The main objectives of this work were the acquisition of new data on floating marine macro litter (FMML) and natural floating objects in the Arctic seas, an initial assessment of the level of pollution by FMML and an analysis of potential sources. The results of this study present the first data on FMML distribution in Russian Arctic shelf seas in relation to oceanographic conditions (i.e.

Source apportionment of methane escaping the subsea permafrost system in the outer Eurasian Arctic Shelf.

The East Siberian Arctic Shelf holds large amounts of inundated carbon and methane (CH). Holocene warming by overlying seawater, recently fortified by anthropogenic warming, has caused thawing of the underlying subsea permafrost. Despite extensive observations of elevated seawater CH in the past decades, relative contributions from different subsea compartments such as early diagenesis, subsea permafrost, methane hydrates, and underlying thermogenic/ free gas to these methane releases remain elusive.

The role of the cadmium-binding protein response of the digestive gland of the Yesso scallop Mizuhopecten yessoensis (Jay, 1857) for marine environmental assessments.

The ability of Pectinidae to accumulate heavy metals and store them in their tissues allows the use of scallops for biomonitoring marine pollution. High molecular weight metallothionein (MT)-like proteins (MTlps) play a central role in this process. Two major MTlps (72 and 43 kDa) have been identified in the digestive glands of Mizuhopecten yessoensis (Yesso scallop).

Trace metals in deep-sea sediments collected from Kuril Basin (Sea of Okhotsk) and Kuril-Kamchatka Trench area.

Heavy metal concentrations in deep-sea sediments collected from Kuril Basin (Sea of Okhotsk) and Kuril-Kamchatka Trench area were analyzed. For the Kuril Basin, a geochemical natural background of these elements was identified based on a dated core. The results showed enrichment by heavy metals due to natural factors in the study area.

Migrations of young spotted seals (Phoca largha) from Peter the Great Bay, Sea of Japan/East Sea, and the pattern of their use of seasonal habitats.

We studied the migrations of young spotted seals during their annual cycle. In May 2017, we attached satellite tags (SPOT-293A) to three individuals (two underyearlings and one yearling) captured at their breeding ground in Peter the Great Bay, western Sea of Japan/East Sea. The operational time of the installed tags ranged from 207 to 333 days; a total of 27195 locations were uploaded.

Supersensitive Detector of Hydrosphere Pressure Variations.

This paper presents an instrument based on an equal-arm Michelson interferometer and a frequency-stabilized helium-neon laser. It is designed to record hydrosphere pressure variations in the frequency range from 0 (conventionally) to 1000 Hz, with accuracy of 0.24 mPa at sea depths of up to 50 m.

Distribution of atmospheric gaseous elemental mercury (Hg(0)) from the Sea of Japan to the Arctic, and Hg(0) evasion fluxes in the Eastern Arctic Seas: Results from a joint Russian-Chinese cruise in fall 2018.

The Eastern Arctic Seas and the north-western Pacific are among the most poorly investigated areas as far as Hg cycling in marine systems is concerned. Continuous measurements of gaseous elemental mercury (Hg(0)) concentrations in the marine boundary layer and Hg(0) evasion fluxes from the sea surface were performed in these regions in fall 2018. Atmospheric Hg(0) concentrations of 1.

Polycyclic Aromatic Hydrocarbons in the Estuaries of Two Rivers of the Sea of Japan.

The seasonal polycyclic aromatic hydrocarbon (PAH) variability was studied in the estuaries of the Partizanskaya River and the Tumen River, the largest transboundary river of the Sea of Japan. The PAH levels were generally low over the year; however, the PAH concentrations increased according to one of two seasonal trends, which were either an increase in PAHs during the cold period, influenced by heating, or a PAH enrichment during the wet period due to higher run-off inputs. The major PAH source was the combustion of fossil fuels and biomass, but a minor input of petrogenic PAHs in some seasons was observed.

Correlation of the siboglinid (Annelida: Siboglinidae) distribution to higher concentrations of hydrocarbons in the Sea of Okhotsk.

Siboglinids are a characteristic feature of reducing environments. More than 75% of all siboglinids were found in the Sea of Okhotsk at a depth of less than 400 m, while some species are known to inhabit the abyssal depth in other regions. Among the six species of siboglinids encountered in the Sea of Okhotsk, only two are widespread: Siboglinum caulleryi and Oligobrachia dogieli.

Clustering of floating tracers in weakly divergent velocity fields.

This work deals with buoyant tracers floating at the ocean surface, where the geostrophic velocity component is two dimensional and rotational (nondivergent) and the ageostrophic component can contain rotational and potential (divergent) contributions that are comparable in size. We consider a random kinematic flow model and study the process of clustering, that is, aggregation of the floating tracer in localized spatial patches. In the long-time limit and in the cases of strongly and weakly divergent flows, the existing analytical theory predicts the process of exponential clustering, which is the emergence of spatial singularities containing all the available tracer.

Different Macrophage Type Triggering as Target of the Action of Biologically Active Substances from Marine Invertebrates.

Macrophages play a fundamental role in the immune system. Depending on the microenvironment stimuli, macrophages can acquire distinct phenotypes characterized with different sets of the markers of their functional activities. Polarization of macrophages towards M1 type (classical activation) is involved in inflammation and the related progression of diseases, while, in contrast, alternatively activated M2 macrophages are associated with the anti-inflammatory mechanisms.

Signatures of Molecular Unification and Progressive Oxidation Unfold in Dissolved Organic Matter of the Ob-Irtysh River System along Its Path to the Arctic Ocean.

The Ob-Irtysh River system is the seventh-longest one in the world. Unlike the other Great Siberian rivers, it is only slightly impacted by the continuous permafrost in its low flow. Instead, it drains the Great Vasyugan mire, which is the world largest swamp, and receives huge load of the Irtysh waters which drain the populated lowlands of the East Siberian Plain.

Entanglement of northern fur seals (Callorhinus ursinus) in marine debris on Tyuleniy Island (Sea of Okhotsk) in 1998-2013.

The systematic annual observations of the northern fur seal rookery on Tyuleniy (= Robben) Island, Sea of Okhotsk, were started in 1958. Since 1975, all seals entangled in marine debris have been registered. Some of the data on this issue, collected on the island in the late 20th century, were published earlier.

Long-term study of behaviors of two cohabiting sea urchin species, and , under conditions of high food quantity and predation risk in situ.

Background: In the predator-sea urchin-macrophyte trophic cascade, the ecological effect of sea urchins as grazers depends both on their density and the changes in foraging activity, which are influenced by various disturbing factors. However, the complete duration of the alarm reactions of echinoids has not been studied until now. Here, we tested a hypothesis that two cohabiting sea urchins, and , which differ morphologically, might display different behavioral responses to high hydrodynamic activity and predation.

Organochlorine pesticides (HCH and DDT) in blubber of spotted seals (Phoca largha) from the western Sea of Japan.

In 2014-2019, a total of 31 blubber samples were collected from spotted seals (Phoca largha) in the western Sea of Japan. The samples were analyzed by gas chromatography to determine level of organochlorine pesticides (OCPs). The concentration of hexachlorocyclohexane and its isomers (∑HCH) ranged from 389 to 50,070 ng/g lipid weght; the concentration of dichlorodiphenyltrichloroethane and its metabolites (∑DDT), ranged from 62,720 to 1,110,930 ng/g lipid wt.

Whispering gallery waves localized near circular isobaths in shallow water.

Sound propagation in an area of shallow sea with circular isobaths and the bottom depth increasing towards their curvature center is considered. Such an area could be part of a bay, a lagoon, or a lake with bowl-like bottom relief. The possible formation of whispering gallery waves localized in the vicinity of curved isobaths is considered.