Responses of zebra and quagga mussels to copper and tribytiltin exposure: Bioconcentration, metabolic and cardiac biomarkers.

One of the top ecological priorities is to find sensitive indicators for pollution monitoring. This study focuses on the bioconcentration and responses (condition index, survival, oxygen consumption, heart rates, and oxidative stress and neurotoxic effect biomarkers) of mussels from the Volga River basin, Dreissena polymorpha and Dreissena bugensis, to long-term exposure to toxic chemicals such as tributyltin (TBT, 25 and 100 ng/L) and copper (Cu, 100 and 1000 μg/L). We found that TBT was present in the tissues of zebra and quagga mussels in comparable amounts, whereas the bioconcentration factor of Cu varied depending on its concentration in water.

Year-Round Presence of Microcystins and Toxin-Producing in the Water Column and Ice Cover of a Eutrophic Lake Located in the Continuous Permafrost Zone (Yakutia, Russia).

This study aimed to test the hypothesis of the year-round presence of toxigenic and cyanotoxins in the water and ice of the shallow eutrophic Lake Ytyk-Kyuyol located in the continuous permafrost zone. Three independent approaches-mass-spectrometry, molecular methods and light microscopy-were applied in the study. The cyanobacterial biomass ranged from 1.

A microcosm approach for evaluating the microbial nonylphenol and butyltin biodegradation and bacterial community shifts in co-contaminated bottom sediments from the Gulf of Finland, the Baltic Sea.

Pollution of aquatic ecosystems with nonylphenol (NP) and butyltins (BuTs) is of great concern due to their effects on endocrine activity, toxicity to aquatic organisms, and extended persistence in sediments. The impact of contamination with NP and/or BuTs on the microbial community structure in marine sediments was investigated using microcosms and high-throughput sequencing. Sediment microcosms with NP (300 mg/kg) and/or BuTs (95 mg/kg) were constructed.

Organotin compounds (OTs) in surface sediments, bivalves and algae from the Russian coast of the Barents Sea (Kola Peninsula) and the Fram Strait (Svalbard Archipelago).

Organotin pollution in components of benthic ecosystems was investigated in 2019 in the Barents Sea (South shore, Kola Peninsula) and the Fram Strait (Icefjord, Svalbard Archipelago). Six species of organotin compounds (OTs), including monobutyltin, dibutyltin, tributyltin, tetrabutyltin, triphenyltin and tricyclohexyltin, were measured in the surface sediments, bivalve molluscs (Ciliatocardium ciliatum, Macoma calcarea, Chlamys islandica) and macrophyte algae (Saccharina latissima, Palmaria palmata, Ulvaria obscura, Fucus serratus, Fucus distichus). The results obtained showed moderate contamination of the studied samples with OTs.

Organotin Compounds (OTCs) in Saccharina latissima (Phaeophyceae) from the Barents Sea.

The degree of contamination of Saccharina latissima, the dominant species among macrophyte algae in the sublittoral zones of the Kola Bay and Eastern Murman of the Barents Sea, with organotin compounds (monobutyltin, dibutyltin, tributyltin, tetrabutyltin, triphenyltin, and tricyclohexyltin) has been assessed. The results show a moderate degree of contamination of the studied samples with organotin compounds. The total concentration of six tin compounds was 17-74 ng/g (dry weight) in algal samples.

First observation of microcystin- and anatoxin-a-producing cyanobacteria in the easternmost part of the Gulf of Finland (the Baltic Sea).

The aim of this study was to obtain the first data on the occurrence and distribution of potentially toxic cyanobacteria and cyanotoxins in the Russian Easternmost part of the Gulf of Finland of the Baltic Sea. Studied samples were collected from 2012 to 2017 and three independent approaches - HPLC-HRMS, PCR and light microscopy were applied for cyanotoxins analysis and detection of toxigenic cyanobacteria. Aphanizomenon flos-aquae Ralfs ex Born.

Participation of the Green Algae Ulvaria obscura in Bioremediation of Sea Water from Oil Products.

Participation of green algae in bioremediation of sea water from oil products (OPs) has been studied. Decrease in the content of OPs in water is accompanied by their accumulation by the alga Ulvaria obscura (Chlorophyta). It has been assumed that neutralization of OPs in Ulvaria occurs, similarly to Fucus vesiculosus (Phaeophyta), all over the thallome: destruction of OPs starts on the alga surface by epiphytic hydrocarbonoxidizing bacteria providing absorption and subsequent degradation of OPs by plant cells.

Occurrence of PCDD/PCDFs, dioxin-like PCBs, and PBDEs in surface sediments from the Neva River and the Eastern Gulf of Finland (Russia).

A total of 26 samples of surface sediments collected in the Neva River (including the St. Petersburg city area) and in the Russian part of the Gulf of Finland were analyzed for 17 polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), 12 dioxin-like polychlorinated biphenyls (dl-PCBs), and 10 polybrominated diphenyl ethers (PBDEs). The concentrations of total PCDD/Fs and dl-PCBs in sediments ranged from < 0.

Gas chromatographic identification of chlorination products of aliphatic ketones.

Chlorinated derivatives of aliphatic ketones are a class of organic compounds poorly characterized by both mass spectra and chromatographic retention indices up to present. It is caused by objective difficulties of isolation of individual products from reaction mixtures formed in the result of non-selective chlorination of parent carbonyl compounds. Nevertheless the differences of GC retention indices for structurally analogous chlorination products of different ketones and initial substrates indicate the constancy depending on the number and position of chlorine atoms in the molecules.