The study on contamination of bottom sediments from the Odra River estuary (SW Baltic Sea) by tributyltin using environmetric methods.

We present the first comprehensive study on the occurrence of tributyltin (TBT) in the Odra River estuary (SW Baltic Sea) that encompasses both densely populated and urbanized agglomeration Szczecin city, and sparsely populated biosphere reserves "Natura 2000". Relationship between TBT and physicochemical parameters of bottom sediments such as granulometry total organic carbon (TOC), total nitrogen (TN), acid volatile sulfide (AVS), As, and metals: Ba, Cd, Co, Cr, Cu, Fe, Hg, Ni, Mn, Mo, Pb, Sn, and Zn was investigated in 120 samples collected in 2017 and 2018. The highest TBT concentrations were over 3000 ng g-1 (dry weight). They were observed in samples collected in the vicinity of the ship maintenance zones of the Szczecin city. Despite the EU ban on its use since 2003, TBT is still present in the environment. Environmetrics analyses such as correlation, cluster, and principal component analysis of obtained results revealed that the main source of sediments contamination by TBT, metalloids, and metals is likely related to the maritime industry: shipyards, ship maintenance as well as ports and marines. TBT is still present in the bottom sediments because of its emission to the environment with dust and paint chips formed during sandblasting cleaning of ship surfaces. The pollutant is further transported with water current to remote localization in the Szczecin Lagoon. Slow water exchange between the Szczecin Lagoon and the Baltic Sea favors accumulation of pollutants in the lagoon sediments. Therefore, it is necessary to implement environmentally friendly methods into ship maintenance and management of the materials from dredged waterways, harbors, and marinas.

Fit-for-Purpose Assessment of QuEChERS LC-MS/MS Methods for Environmental Monitoring of Organotin Compounds in the Bottom Sediments of the Odra River Estuary.

Organotin compounds (OTCs) are among the most hazardous substances found in the marine environment and can be determined by either the ISO 23161 method based on extraction with non-polar organic solvents and gas chromatography analysis or by the recently developed QuEChERS method coupled to liquid chromatography-mass spectrometry (LC-MS/MS). To date, the QuEChERS LC/MS and ISO 23161 methods have not been compared in terms of their fit-for-purpose and reliability in the determination of OTCs in bottom sediments. In the case of ISO 23161, due to a large number of interferences gas chromatography-mass spectrometry was not suitable for the determination of OTCs contrary to more selective determination by gas chromatography with an atomic emission detector. Moreover, it has been found that the derivatization of OTCs to volatile compounds, which required prior gas chromatography determination, was strongly affected by the sediments' matrices. As a result, a large amount of reagent was needed for the complete derivatization of the compounds. Contrary to ISO 23161, the QuEChERS LC-MS/MS method did not require the derivatization of OTC and is less prone to interferences. Highly volatile and toxic solvents were not used in the QuEChERS LC-MS/MS method. This makes the method more environmentally friendly according to the principles of green analytical chemistry. QuEChERS LC-MS/MS is suitable for fast and reliable environmental monitoring of OTCs in bottom sediments from the Odra River estuary. However, determination of di- and monobutyltin by the QuEChERS LC-MS/MS method was not possible due to the constraints of the chromatographic system. Hence, further development of this method is needed for monitoring di- and monobutyltin in bottom sediments.

The assessment of environmental risk related to the occurrence of pharmaceuticals in bottom sediments of the Odra River estuary (SW Baltic Sea).

The occurrence of 130 pharmaceutically active compounds (PhACs) in sediments collected from 70 sampling sites in the Odra River estuary (SW Baltic Sea) was investigated. The highest concentration levels of the compounds were found in the vicinity of effluent discharge from two main Szczecin wastewater treatment plants: "Pomorzany" and "Zdroje", and nearby the seaport and shipyard. The highest environmental risks (RQ > 1) were observed for pseudoephedrine (RQ = 14.0), clindamycin (RQ = 7.3), nalidixic acid (RQ = 3.8), carbamazepine (RQ = 1.8), fexofenadine (RQ = 1.4), propranolol (RQ = 1.1), and thiabendazole (RQ = 1.1). RQ for each compound varied depending on the sampling sites. High environmental risk was observed in 30 sampling sites for clindamycin, 22 sampling sites for pseudoephedrine, 19 sampling sites for nalidixic acid, 4 sampling sites for carbamazepine, and 3 sampling sites for fexofenadine. The medium environmental risk (0.1 < RQ < 1) was observed for 16 compounds: amisulpride, amitriptyline, amlodipine, atropine, bisoprolol, chlorpromazine, lincomycin, metoprolol, mirtazapine, moclobemide, ofloxacin, oxazepam, tiapride, tolperisone, verapamil, and xylometazoline. Due to the scarcity of toxicological data related to benthic organisms, only an approximate assessment of the environmental risk of PhACs is possible. Nevertheless, the compounds with medium and high risk should be considered as pollutants of high environmental concern whose occurrence in the environment should remain under close scrutiny.

Development and Application of a Novel QuEChERS Method for Monitoring of Tributyltin and Triphenyltin in Bottom Sediments of the Odra River Estuary, North Westernmost Part of Poland.

A Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method combined with Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) for determination of organotin compounds (OTC) has been newly developed. The novel analytical method was validated and the quality of the results was tested by the use of certificate reference material of freshwater sediment BCR 646. The method was applied in determination of OTC concentration in real samples of bottom sediments collected from the Polish part of Odra River Estuary. The samples came from locations with different anthropogenic impact. Additionally, the extraction recovery of OTC and matrix effect on MS signal response was investigated based on those real environmental samples. It was found that organic compounds and anthropogenic contaminations present in bottom sediments may affect extraction efficiency of the organotin compounds (OTC) and change the matrix effect on MS signal response. The highest concentrations of tributyltin were found in bottom sediments collected from locations in vicinity of the Szczecin harbor and shipyards. The presence of triphenyltin above limit of detection (5 ng TPhT/g of sediment) was observed only in two samples and its concentration was several times lower compared to concentration of tributyltin (from 58 ng/g to 5263 ng/g). In spite of the fact that, the application of TBT-based paints on hull of vessel entering EU ports has been banned by European Commission regulation No. 782/2003 since 2008, the OTC compounds are still present in bottom sediment and pose significant threat to the environment. This threat should be taken into account during dredging of waterways and other hydrotechnical works.