Biljana Škrbić

Determination of 81 pharmaceutical drugs by high performance liquid chromatography coupled to mass spectrometry with hybrid triple quadrupole-linear ion trap in different types of water in Serbia.

The aim of the work was to study the occurrence of pharmaceuticals in waste, surface, underground, and drinking water samples collected in Serbia. A multi-residue method for the analysis of 81 pharmaceutical drugs from different therapeutic classes in the various types of water was applied. Twenty-five composite water samples were prepared using solid-phase extraction and the presence of 81 pharmaceutical compounds in the extracts was analyzed by ultra-high performance liquid chromatography coupled to mass spectrometry with hybrid triple quadrupole-linear ion trap (UPLC-QqLIT-MS/MS). Forty seven compounds of 81 drugs were found in four different types of analyzed water. The highest concentrations of ibuprofen of 20.1 μg L(-1), 10,11-epoxycarbamazepine of 16.2 μg L(-1), 2-hydroxycarbamazepine of 15.9 μg L(-1) and acetaminophen of 15.7 μg L(-1) were found in municipal waste water sample. Results revealed the presence of salicylic acid in 41.67% of water samples, carbamazepine in 36.11%, propranolol and irbesartan in 30.56%. The obtained results were discussed in relation to the relevant data available in literature. This is the first attempt to assess the occurrence of these 81 pharmaceutical residues in water samples in Serbia.

Removal of water turbidity by natural coagulants obtained from chestnut and acorn

The ability of seed extracts of several species of chestnut and acorn to act as natural coagulants was tested using a synthetic turbid water. Active components were extracted from ground seeds of Horse chestnut and acorns of some species of family Fagaceae: Common oak, Turkey oak, Northern red oak and European chestnut. All investigated extracts had coagulation capabilities and their amounts depended on pH values and initial turbidities. The seed extracts from European chestnut and Common oak acorn were the most efficient expressing the highest coagulation activities, about 80% and 70%, respectively, in both low and medium investigated water turbidities at the lowest coagulant dose 0.5 ml/L.

Assessment of perfluoroalkyl substances in food items at global scale

This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from Brazil, 35 from Saudi Arabia, 174 from Spain and 36 from Serbia) among the most widely consumed foodstuffs in these geographical areas. These countries were chosen as representatives of the diet in South America, Western Asia, Mediterranean countries and South-Eastern Europe. The analysis of foodstuffs was carried out by turbulent flow chromatography (TFC) combined with liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS) using electrospray ionization (ESI) in negative mode. The analytical method was validated for the analysis of different foodstuff classes (cereals, fish, fruit, milk, ready-to-eat foods, oil and meat). The analytical parameters of the method fulfill the requirements specified in the Commission Recommendation 2010/161/EU. Recovery rates were in the range between 70% and 120%. For all the selected matrices, the method limits of detection (MLOD) and the method limits of quantification (MLOQ) were in the range of 5 to 650 pg/g and 17 to 2000 pg/g, respectively. In general trends, the concentrations of PFASs were in the pg/g or pg/mL levels. The more frequently detected compounds were perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA). The prevalence of the eight-carbon chain compounds in biota indicates the high stability and bioaccumulation potential of these compounds. But, at the same time, the high frequency of the shorter chain compounds is also an indication of the use of replacement compounds in the new fluorinated materials. When comparing the compounds profile and their relative abundances in the samples from diverse origin, differences were identified. However, in absolute amounts of total PFASs no large differences were found between the studied countries. Fish and seafood were identified as the major PFASs contributors to the diet in all the countries. The total sum of PFASs in fresh fish and seafood was in the range from the MLOQ to 28ng/g ww. According to the FAO-WHO diets composition, the daily intake (DI) of PFASs was calculated for various age and gender groups in the different diets. The total PFASs food intake was estimated to be between 2300 and 3800 ng /person per day for the different diets. Finally, the risk intake (RI) was calculated for selected relevant compounds. The results have indicated that by far in no case the tolerable daily intake (TDI) (150, 1500, 50,000, 1,000,000, 150, 1500 ng/kg body weight, for perfluorohexanesulfonate (PFHxS), fluorotelomer alcohol (FTOH), perfluorobutanesulfonic acid (PFBS), perfluorobutanoic acid (PFBA), PFOS and PFOA, respectively) was exceeded.

Modified hardwood sawdust as adsorbent of heavy metal ions from water

The sawdust of oak and black locust hardwood was found to have good adsorption capacities for heavy metal ions. The leaching of coloured organic matters during the adsorption can be prevented by each of the following pre-treatments of adsorbents: with formaldehyde in acidic medium, with sodium hydroxide solution after formaldehyde treatment, or with sodium hydroxide only. The studies indicated that the leaching of coloured matters from modified hardwood sawdust was less than that from unmodified hardwood sawdust, namely between 70 and 94%, dependent on wood species and the method of modification. At the same time, adsorption capacities of modified adsorbents were higher than unmodified adsorbents when sodium hydroxide was applied for modification. When formaldehyde was applied for modification, the adsorption capacities of adsorbents remained unchanged. Only the application of sodium hydroxide was recommended for modification of hardwood sawdust.

Polycyclic Aromatic Hydrocarbons in Surface Soils of Novi Sad and Bank Sediment of the Danube River

Abstract Concentrations of 16 EPA polycyclic aromatic hydrocarbons (PAHs) in the surface soil samples of Novi Sad city urban area and in the Danube bank sediment sample were measured in 2001. The sampling sites were chosen in order to cover the whole city area and the results correspond to a network of six representative sampling sites. The total content of PAHs ranged from 307 to 1452 μg/kg with arithmetic mean value of 667 μg/kg and median of 382 μg/kg that represented typical PAH level of soils throughout Novi Sad urban area. Value of total PAHs content obtained in bank sediment sample along the Danube River was 975 μg/kg. Benzo(a)pyrene known to be carcinogenic formed 6–14% of the sum concentration of the identified PAHs for all investigated samples. Data were compared with the ones found for soils and river sediments throughout the world, and with target values set by Dutch authorities for unpolluted soil. The total carcinogenic potency for each sampling site was calculated and compared with the ones obtained on the base of the target concentrations. It was revealed only one sampling site with carcinogenic potency below the value calculated for unpolluted soil.

Trace Metal Distribution in Surface Soils of Novi Sad and Bank Sediment of the Danube River

Abstract Concentration of Cu, Cd, Pb, Zn, As, Mn, and Fe in the Novi Sad city urban area surface soil samples and the Danube bank sediment sample were measured in 2001. The results correspond to a network of six representative sampling sites in which the main soil properties, organic matter, water content, pH, and particle size have also been determined. The geometric mean content of Zn, Cu, Cd, and Pb obtained from soil samples throughout the Novi Sad urban area (61.32, 28.39, 0.151, and 2.70 mg/kg, respectively) was compared with the geometric mean concentration in world soils. It was revealed only one site (sampling site No. 3) with Zn and Cu content higher than the allowed ones set by Dutch authorities used for investigation of a site for possible rehabilitation (Dutch A values).

Status of hormones and painkillers in wastewater effluents across several European states—considerations for the EU watch list concerning estradiols and diclofenac

Present technologies for wastewater treatment do not sufficiently address the increasing pollution situation of receiving water bodies, especially with the growing use of personal care products and pharmaceuticals (PPCP) in the private household and health sector. The relevance of addressing this problem of organic pollutants was taken into account by the Directive 2013/39/EU that introduced (i) the quality evaluation of aquatic compartments, (ii) the polluter pays principle, (iii) the need for innovative and affordable wastewater treatment technologies, and (iv) the identification of pollution causes including a list of principal compounds to be monitored. In addition, a watch list of 10 other substances was recently defined by Decision 2015/495 on March 20, 2015. This list contains, among several recalcitrant chemicals, the painkiller diclofenac and the hormones 17β-estradiol and 17α-ethinylestradiol. Although some modern approaches for their removal exist, such as advanced oxidation processes (AOPs), retrofitting most wastewater treatment plants with AOPs will not be acceptable as consistent investment at reasonable operational cost. Additionally, by-product and transformation product formation has to be considered. The same is true for membrane-based technologies (nanofiltration, reversed osmosis) despite of the incredible progress that has been made during recent years, because these systems lead to higher operation costs (mainly due to higher energy consumption) so that the majority of communities will not easily accept them. Advanced technologies in wastewater treatment like membrane bioreactors (MBR) that integrate biological degradation of organic matter with membrane filtration have proven a more complete elimination of emerging pollutants in a rather cost- and labor-intensive technology. Still, most of the presently applied methods are incapable of removing critical compounds completely. In this opinion paper, the state of the art of European WWTPs is reflected, and capacities of single methods are described. Furthermore, the need for analytical standards, risk assessment, and economic planning is stressed. The survey results in the conclusion that combinations of different conventional and advanced technologies including biological and plant-based strategies seem to be most promising to solve the burning problem of polluting our environment with hazardous emerging xenobiotics.

Principal component analysis of indicator PCB profiles in breast milk from Poland

Principal component analysis (PCA) was applied to a data set containing the levels of indicator polychlorinated biphenyls (PCBs) in human milk of mothers living in the Wielkopolska region, Poland, in order to investigate the information captured in the PCB patterns and to elucidate the relationship between PCB concentrations in milk and donor characteristics. According to the obtained PCA results milk fat content was the most influential factor affecting the PCB levels in milk of the Wielkopolska cohort. The lifestyle data collected from the questionnaire completed by the donors appeared to have no influence on PCB concentrations in breast milk. The score plots revealed the PCB contents of milk were quite low and uniform with a few outliers, without discrimination observed either between the primipareous and secundipareous females or between donors from the urban and rural areas. Comparison of the PCB levels and profiles of human milk from the Wielkopolska region and from various European and Asian locations made by PCA reflected a generally low background exposure and indicated the possible reasons for the outlying of some samples. In order to enhance the chances of observing the relationship between donor habits and PCB levels in breast milk it was suggested that the questionnaire be redesigned to gather information about vegetable product consumption and indoor air exposure.

Ranking and similarity for quantitative structure–retention relationship models in predicting Lee retention indices of polycyclic aromatic hydrocarbons

Quantitative structure-(chromatographic) retention relationship (QSRR) models for prediction of Lee retention indices for polycyclic aromatic hydrocarbons (PAHs) were gathered from the literature and the predictive performances of models were compared. Numerous Lee retention indices (46) were served as a reliable basis for ranking by a recently developed novel method of ordering based on the sum of ranking differences (SRD) [TrAC, Trends Anal. Chem. 29 (2010) 101-109], by which the best model can be selected easily. Two kinds of references for ranking were accepted, average (consensus) and the experimental retention indices. Leave-many-out cross validation of the SRD procedure provides an easy way to group similar models. Significant differences among models can be revealed by using Wilcoxons matched pair test. Principal component analysis (PCA) and cluster analysis (CA) arranged the models in three groups, i.e. similarities among models are manifested. The classical exploratory techniques and cross-validation (CV) justified the findings based on SRD ranking, i.e. the seven fold CV can be applied for pattern recognition. Generalized pair correlation method (GCPM) provided very similar grouping pattern to the procedures based of sum of ranking differences. The two methods (SRD and GPCM) exert astonishingly similar grouping (pattern recognition) though their background philosophy and way of calculation are totally different.

Pre-treatment and extraction techniques for recovery of added value compounds from wastes throughout the agri-food chain

The enormous quantity of food wastes discarded annually forces a look into alternatives for this interesting feedstock. Thus, food bio-waste valorisation is one of the current imperatives of society. This review is the most comprehensive overview of currently existing technologies and processes in this field. It tackles classical and innovative physical, physico-chemical and chemical methods of food waste pre-treatment and extraction for the recovery of added value compounds and detection by modern technologies and is an outcome of the COST Action EUBIS, TD1203 Food Waste Valorisation for Sustainable Chemicals, Materials and Fuels.