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Mira Petrovic

Publications and source records attributed to Mira Petrovic.

18 recordsLinked to original sources
PubMed2006

Removal of a broad range of surfactants from municipal wastewater--comparison between membrane bioreactor and conventional activated sludge treatment.

Elimination of alkylphenol ethoxylates (APEO) and their degradation products (alkylphenols and alkylphenoxy carboxylates), as well as linear alkylbenzene sulfonates (LAS) and coconut diethanol amides (CDEA), was studied in a pilot plant membrane bioreactor (MBR) working in parallel to a full-scale wastewater treatment plant (WWTP) using conventional activated sludge (CAS). In the CAS system 87% of parent long ethoxy chain NPEOs were eliminated, but their decomposition yielded persistent acidic and neutral metabolites which were poorly removed. The elimination of short ethoxy chain NPEOs (NP(1)EO and NP(2)EO) averaged 50%, whereas nonylphenoxy carboxylates (NPECs) showed an increase in concentrations with respect to the ones measured in influent samples. Nonylphenol (NP) was the only nonylphenolic compound efficiently removed (96%) in the CAS treatment. On the other hand, MBR showed good performance in removing nonylphenolic compounds with an overall elimination of 94% for the total pool of NPEO derived compounds (in comparison of 54%-overall elimination in the CAS). The elimination of individual compounds in the MBR was as follows: 97% for parent, long ethoxy chain NPEOs, 90% for short ethoxy chain NPEOs, 73% for NPECs, and 96% for NP. Consequently, the residual concentrations were in the low mug/l level or below it. LAS and CDEA showed similar elimination in the both wastewater treatment systems that were investigated, and no significant differences were observed between the two treatment processes. Nevertheless, for all studied compounds the MBR effluent concentrations were consistently lower and independent of the influent concentrations. Additionally, MBR effluent quality in terms of chemical oxygen demand (COD), NH(4)(+) concentration and total suspended solids (TSS) was always superior to the ones of the CAS and also independent of the influent quality, which demonstrates high potential of MBRs in the treatment of municipal wastewaters.

Alkanesulfonic Acids↗
PubMed2006

Analysis of pharmaceuticals in wastewater and removal using a membrane bioreactor.

Much attention has recently been devoted to the life and behaviour of pharmaceuticals in the water cycle. In this study the behaviour of several pharmaceutical products in different therapeutic categories (analgesics and anti-inflammatory drugs, lipid regulators, antibiotics, etc.) was monitored during treatment of wastewater in a laboratory-scale membrane bioreactor (MBR). The results were compared with removal in a conventional activated-sludge (CAS) process in a wastewater-treatment facility. The performance of an MBR was monitored for approximately two months to investigate the long-term operational stability of the system and possible effects of solids retention time on the efficiency of removal of target compounds. Pharmaceuticals were, in general, removed to a greater extent by the MBR integrated system than during the CAS process. For most of the compounds investigated the performance of MBR treatment was better (removal rates >80%) and effluent concentrations of, e.g., diclofenac, ketoprofen, ranitidine, gemfibrozil, bezafibrate, pravastatin, and ofloxacin were steadier than for the conventional system. Occasionally removal efficiency was very similar, and high, for both treatments (e.g. for ibuprofen, naproxen, acetaminophen, paroxetine, and hydrochlorothiazide). The antiepileptic drug carbamazepine was the most persistent pharmaceutical and it passed through both the MBR and CAS systems untransformed. Because there was no washout of biomass from the reactor, high-quality effluent in terms of chemical oxygen demand (COD), ammonium content (N-NH(4)), total suspended solids (TSS), and total organic carbon (TOC) was obtained.

Anti-Bacterial Agents↗
PubMed2006

Polar pollutants entry into the water cycle by municipal wastewater: a European perspective.

The effluents of eight municipal wastewater treatment plants (WWTP) in Western Europe were analyzed by liquid-chromatography-mass spectrometry for the occurrence of 36 polar pollutants, comprising household and industrial chemicals, pharmaceuticals, and personal care products. In a long-term study of the effluents of three WWTP over 10 months, sulfophenyl carboxylates and ethylene diamino tetraacetate (EDTA) were detected above 10 microg/L on average, while benzotriazoles, benzothiazole-2-sulfonate, diclofenac, and carbamazepine showed mean concentrations of 1-10 microg/L, followed by some flame retardants, naphthalene disulfonates, and personal care products in the range of 0.1-1 microg/L. Half of the determined compounds were not significantly removed in tertiary wastewater treatment. By dividing the effluent concentration of a compound by its relative removal in WWTP a water cycle spreading index (WCSI) was calculated for each compound. We propose that this index provides a measure for the potential of a polar compound to spread along a partially closed water cycle after discharge with municipal wastewater and to occur in raw waters used for drinking water production. Polar pollutants in surface water samples of different catchments showed increasing concentration for compounds with increasing WCSI.

Europe↗
PubMed2006

Multi-residue analysis of pharmaceuticals in wastewater by ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry.

In this work, a new multi-residue method using ultra-performance liquid chromatography (UPLC) quadrupole-time-of-flight mass spectrometry (Q-TOF-MS) was developed for screening and confirmation of 29 pharmaceutical compounds belonging to different therapeutical classes: analgesics and antiinflammatories, lipid regulating agents cholesterol lowering statin agents, psychiatric drugs, anti ulcer agents, histamine H2 receptor antagonist, antibiotics and beta-blockers. UPLC uses columns packed with 1.7 microm particles and enables elution of sample components in much narrower, more concentrated bands, resulting in better chromatographic resolution and increased peak height. The typical peak width was 5-10s at base, permitting very good separation of all compounds in 10 min, which represented an approximate three-fold reduction in the analysis time in comparison to conventional high-performance liquid chromatography (HPLC). Unequivocal identification of target pharmaceutical compounds was based on accurate mass measurement of the molecular ions in the TOF mode and by performing collision induced dissociation (CID) in the Q-TOF mode in order to generate accurate mass measurement of the product ions. Using lock mass correction the accurate masses calculated for the product ions deviated from the theoretical masses by 0.2 to 1.3 mDa (root mean square (RMS) value=0.67) and 0.7-6.4 ppm (RMS=3.53), respectively. Quantitation was carried out working in the TOF mode using the narrow window extracted ion chromatograms (nwXICs) of each compound (extracted using a 20 mDa window) yielding relative standard deviation (RSD) from 0.5 to 5.3% (run-to-run) and from 2.1 to 9.1% (day-to-day) and instrumental detection limits (IDLs) from 1 to 200 pg. Analysis of wastewater treatment plant (WWTP) samples gave method detection limits (MDLs) ranging from 10 to 500 ng/L. The UPLC-Q-TOF method was successfully applied to analyze pharmaceutical residues in WWTP samples.

Chromatography, High Pressure Liquid↗
PubMed2006

Biodegradation studies of selected priority acidic pesticides and diclofenac in different bioreactors.

The biodegradation of selected priority acidic pesticides MCPP, MCPA, 2,4-D, 2,4-DP and bentazone and the acidic pharmaceutical diclofenac was investigated using a membrane bioreactor (MBR) and a fixed-bed bioreactor (FBBR). A pilot plant MBR was fed with raw water spiked with the selected compounds. The experiment was repeated every week during four weeks to enhance the adaptation of microorganisms. In order to further study the biodegradability of these compounds, degradation studies in a FBBR were carried out. All the samples were analysed by solid phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS). The results indicate that in the MBR compounds except for bentazone were eliminated within the first day of the experiment at rates ranging from 44% to 85%. Comparing these results with the degradation rates in the FBBR showed that in the latter only MCPP, MCPA 2,4-D and 2,4-DP were degraded after a much longer adaptation phase of microorganisms.

Bacteria↗
PubMed2004

Simultaneous extraction and fate of linear alkylbenzene sulfonates, coconut diethanol amides, nonylphenol ethoxylates and their degradation products in wastewater treatment plants, receiving coastal waters and sediments in the Catalonian area (NE Spain).

The efficiency of six wastewater treatment plants (WWTPs) in the Catalonian region to remove several classes of ionic and non-ionic surfactants was investigated, using solid-phase extraction (SPE) followed by liquid chromatography-mass spectrometry (LC-MS). Occurrence and distribution of linear alkylbenzene sulfonates (LASs), coconut diethanol amides (CDEAs), nonylphenol ethoxylates (NPEOs) and their degradation products were studied in coastal areas receiving WWTP effluents. For the analysis of sediment samples pressurized liquid extraction (PLE) followed by SPE extract clean-up and LC-MS detection was used for simultaneous extraction of all target compounds. Concentrations of parent long ethoxy chain NPEOs in raw water entering WWTPs ranged from 60 to 190 microg/L. In effluents concentrations ranged from 2.8 to 6.6 microg/L, which corresponded to an average primary elimination of 93-96%. Nonylphenol (NP) was found in concentrations from 0.2 to 18 microg/L in WWTP influents and up to 5 microg/L in the treated water, showing a clear declining trend with respect to concentrations reported in the last 5 years. The elimination of LASs and CDEAs varied depending on the WWTP and was higher than 85% in well operated WWTPs with secondary treatment and only 56% (for CDEAs) and 30% (for LAS) in WWTPs with primary treatment. Levels up to 86 mg/kg of LAS, 1.7 mg/kg of NP, 400-760 microg/L for NPEOs and NPECs were detected in sediments at sampling points near the discharge of WWTP effluents, clearly showing that in coastal area receiving WWTP effluents surfactants and their degradation products are widespread contaminants.

Amides↗
PubMed2004

Estrogenic potential of halogenated derivatives of nonylphenol ethoxylates and carboxylates.

Halogenated derivatives of nonylphenol and of its alkylates are generated during drinking water disinfection and treatment procedures. In this paper we analyze the potential of these compounds to interact with the estrogen receptor and to activate hormone-regulated gene promoters. We used the recombinant yeast assay (RYA) and the human breast cancer cell MCF7 proliferation assay for both estrogenic and antiestrogenic activities and the enzyme-linked receptor assay to examine in vitro binding to the receptor. Many nonylphenol derivatives were very weak estrogens in our functional tests when compared to nonylphenol while retaining a substantial affinity for the estrogen receptor in vitro. Antiestrogenicity tests demonstrated that brominated nonylphenol and most of the carboxylated compounds studied here behaved as estrogenic antagonists in the RYA. We also detected an increased cytotoxicity for the carboxylated derivatives in both yeast and mammalian cells. We conclude that derivatization may mask the apparent estrogenicity of nonylphenol, but the resulting compounds still represent a potential hazard since they are still able to bind the estrogen receptor and to influence the physiological response to estrogens. Our results also illustrate the advantage of combining different methods to assay estrogenicity of unknown substances.

Binding, Competitive↗
PubMed2003

Application of chemometric methods to the investigation of main microcontaminant sources of endocrine disruptors in coastal and harbour waters and sediments.

Identification, resolution and distribution of main microcontaminant sources of endocrine disruptors in Spanish harbours, coastal waters and sediments are investigated using chemometric methods. We investigated eighteen different endocrine disruptor chemical compounds, including non-ionic surfactants, their degradation products and linear alkylbenzene sulfonates, found in a total number of 74 samples (35 water samples and 39 sediment samples) over a period of 16 months from March 1999 to July 2000, and in 32 different geographical sites along the Spanish Mediterranean Coast (e.g. Barcelona, Tarragona, Almeria Harbour, Malaga and the Bay of Cadiz). Main environmental contamination sources of these endocrine disruptor compounds were investigated and interpreted according to their chemical composition and according to their resolved geographical distribution profiles.

Geologic Sediments↗
PubMed2003

Integrated procedure for determination of endocrine-disrupting activity in surface waters and sediments by use of the biological technique recombinant yeast assay and chemical analysis by LC-ESI-MS.

An integrated procedure using mass spectrometry and molecular biology for determination of estrogenicity in natural waters and sediments is reported. Solid-phase extraction (SPE) and pressurized-liquid extraction (PLE), respectively, were used for isolation of endocrine-disrupting compounds (EDC) from surface waters and sediments, followed by liquid chromatography-mass spectrometry using an electrospray interface (LC-ESI-MS). Twenty seven EDC were determined: non-ionic surfactants (nonylphenol ethoxylate), alkylphenols (e.g. nonylphenol and octylphenol), bisphenol A, phthalates, and natural and synthetic steroid sex hormones. Limits of detection varied from 0.02 to 0.22 microg L(-1) and from 1 to 10 microg kg(-1) in water and sediments, respectively. Recoveries ranged from 65 to 125% and 73 to 97% for waters and sediments, respectively. In addition to LC-ESI-MS determination, extracts obtained by SPE and PLE were analyzed by the recombinant yeast assay (RYA) to assess total estrogenic activity. This bioassay detects natural estrogens and xenoestrogens, producing a quantitative measurement of EDC irrespective of the identity of the chemical responsible for the activity. As a novelty, a relative estrogenicity factor was determined for 19 analytes with EC(50) values ranging from 10(-10) to 10(-9) mol L(-1) for synthetic estrogens, from 10(-7) to 10(-5) mol L(-1) for alkylphenol derivatives, and from 10(-5) to 10(-4) mol L(-1) for phthalates and benzothiazoles. By use of this integrated chemical-ecotoxicological approach good correlation was usually established between chemical composition and estrogenic effects for surface water and sediment samples from Portugal. Estrogenic activity observed was mainly attributed to the presence of nonylphenolic compounds (with concentrations of NP ranging from 0.1 up to 44 microg L(-1) in waters and up to 1172 microg kg(-1) in sediments), and to the sporadic presence of estrogens, detected at ng L(-1) levels.

Chromatography, High Pressure Liquid↗
PubMed2003

Occurrence and removal of estrogenic short-chain ethoxy nonylphenolic compounds and their halogenated derivatives during drinking water production.

The elimination of nonylphenol (NP), nonylphenol mono- and diethoxylates (NP1EO and NP2EO), nonylphenol carboxylates (NP1EC and NP2EC) and their brominated and chlorinated derivatives during drinking water treatment process in Sant Joan Despf waterworks in Barcelona was investigated utilizing a recently developed, highly sensitive LC-MS-MS method. The concentration of these potentially estrogenic compounds in raw water entering waterworks (taken from the Llobregat River, NE Spain) ranged from 8.3 to 22 microg/L, with NP2EC being the most abundant compound. Prechlorination reduced the concentration of short-chain ethoxy NPECs and NPEOs by about 25-35% and of NP by almost 90%. However, this reduction of concentrations was partially due to their transformation to halogenated derivatives. After prechlorination, halogenated nonylphenolic compounds represented approximately 13% of the total metabolite pool, of which 97% were in the form of brominated acidic metabolites. The efficiency of further treatment steps to eliminate nonylphenolic compounds (calculated for the sum of all short-chain ethoxy metabolites including halogenated derivatives) was as follows: settling and flocculation followed by rapid sand filtration (7%), ozonation (87%), GAC filtration (73%), and final disinfection with chlorine (43%), resulting in overall elimination ranging from 96 to 99% (mean 98% for four sampling dates). A few of the nonylphenolic compounds (NP, NP1EC, and NP2EC) were also identified in drinking water; however, the residues detected were generally below 100 ng/L, with one exception for NP2EC in November 2001 when a concentration of 215 ng/L was detected.

Estrogens, Non-Steroidal↗
PubMed2003

Liquid chromatography-(tandem) mass spectrometry of selected emerging pollutants (steroid sex hormones, drugs and alkylphenolic surfactants) in the aquatic environment.

Among the various compounds considered as emerging pollutants, alkylphenolic surfactants, steroid sex hormones, and pharmaceuticals are of particular concern, both because of the volume of these substances used and because of their activity as endocrine disruptors or as causative agents of bacterial resistance, as is the case of antibiotics. Today, the technique of choice for analysis of these groups of substances is liquid-chromatography coupled to mass spectrometry (LC-MS) and tandem mass spectrometry (LC-MS-MS). In the last decades, this technique has experienced an impressive progress that has made possible the analysis of many environmental pollutants in a faster, more convenient, and more sensitive way, and, in some cases, the analysis of compounds that could not be determined before. This article reviews the LC-MS and LC-MS-MS methods published so far for the determination of alkylphenolic surfactants, steroid sex hormones and drugs in the aquatic environment. Practical considerations with regards to the analysis of these groups of substances by using different mass spectrometers (single quadrupole, ion trap and triple quadrupole instruments, etc.), interfaces and ionization and monitoring modes, are presented. Sample preparation aspects, with special focus on the application of advanced techniques, such as immunosorbents, restricted access materials and molecular imprinted materials, for extraction/purification of aquatic environmental samples and extracts are also discussed.

Chromatography, Liquid↗
PubMed2002

Recent advances in the mass spectrometric analysis related to endocrine disrupting compounds in aquatic environmental samples.

An overview of mass spectrometric methods used for the determination of endocrine disrupting compounds (EDCs) in environmental samples is presented. Among the EDCs we have selected five groups of compounds that are of priority within European Union and US research activities: alkylphenols, polychlorinated compounds (dioxins, furans and biphenyls), polybrominated diphenyl ethers, phthalates and steroid sex hormones. Various aspects of current LC-MS and GC-MS methodology, including sample preparation, are discussed.

Endocrine Glands↗
PubMed2002

Column-switching system with restricted access pre-column packing for an integrated sample cleanup and liquid chromatographic-mass spectrometric analysis of alkylphenolic compounds and steroid sex hormones in sediment.

A novel methodology based on column switching LC-MS, using restricted access material (RAM), for an integrated sample clean-up and analysis of endocrine disrupting compounds in sediment samples is described. The use of RAM precolumns, that combines size exclusion and reversed-phase retention mechanisms, enables fast on-line clean-up of sediment extracts and sensitive determination of alkylphenolic compounds, bisphenol A and steroid sex hormones at low ppb level (LODs=0.5-5 ng/g). Different LiChrospher ADS RAM precolumns (Merck, Germany) with C4, C8 and C18, respectively, modification of inner pore surface were tested. ADS C4 precolumns gave the best results in terms of recovery, selectivity and sensitivity, eliminating efficiently matrix components and consequently reducing ion suppression effects. Except for the most polar compounds, all compounds exhibit complete recovery with RSD from 0.87 to 15%. A complete analysis, including efficient pressurized liquid extraction (PLE) of target compounds, on-line clean-up, chromatographic separation and MS detection takes approximately 2 h, which is a significant improvement in comparison to the methods reported previously.

Chromatography, Liquid↗
PubMed2002

Pressurized liquid extraction followed by liquid chromatography-mass spectrometry for the determination of alkylphenolic compounds in river sediment.

A new methodology based on pressurized liquid extraction (PLE) followed by LC-MS is presented for the simultaneous and unequivocal determination of alkylphenol ethoxylates (APEOs) and their degradation products, alkylphenols (APs) and alkylphenoxy carboxylates (APECs), in sediment samples. The protocol, applicable to a full range of APEO oligomers and degradation products, permits the sensitive and selective determination of APEOs (nEO = 1-15), APECs (nEO = 0-1) and APs at low ppb levels (LODs = 1-5 microg/kg) in sediment samples. Optimization of the operational parameters of PLE clearly demonstrates that significant thermal losses of APs occur during extraction at elevated temperatures. The loss of octylphenol (OP) at 100 degrees C was 61.2% and of nonylphenol (NP) 40.0%, whereas other compounds were completely recovered. Thus, to avoid losses due to the volatility of alkylphenols, a low extraction temperature should be applied. The conditions that gave the best results for all target compounds were as follows: extraction solvent mixture, methanol-acetone (1:1, v/v); temperature, 50 degrees C; pressure, 1500 p.s.i.; two static cycles. Using PLE and a subsequent clean-up with solid-phase extraction (SPE), the simultaneous extraction of APEOs, APs and APECs from sediment samples was achieved yielding recoveries >70% and producing low MS background noise. The developed methodology was applied on a routine basis to the analysis of alkylphenolic compounds in sediment samples. APEOs and their persistent degradation products were detected in significant concentrations in sediments from Portuguese rivers, especially at sites situated in the proximity of industrial plants (mainly the textile industry). The total concentration of alkylphenolic compounds (APEOs+APs+APECs) ranged from 155 to 2400 microg/kg. Of all the alkylphenolic compounds, NP comprised 40 to 50% with concentrations up to 1172 microg/kg.

Chromatography, High Pressure Liquid↗
PubMed2002

Occurrence and distribution of nonionic surfactants, their degradation products, and linear alkylbenzene sulfonates in coastal waters and sediments in Spain.

Spain is one of the European countries that still discharges untreated wastewaters and sewage sludge to the sea. A total of 35 samples of coastal waters and 39 samples of harbor sediments was analyzed. Samples were collected from several hot spots on the Spanish coast, such as the harbors of Tarragona, Almería, and Barcelona, the mouths of the Besos and Llobregat rivers, the Bay of Cadiz, and various yacht harbors at the Mediterranean coast. A generic analytical procedure based on solid-phase extraction-liquid chromatography-atmospheric pressure chemical ionization/electrospray ionization mass spectrometry (SPE-LC-APCI/ESI-MS) was employed for determining the concentrations of alcohol ethoxylates (AEO), nonylphenol ethoxylates (NPEO), coconut diethanol amides (CDEA), nonylphenoxy-monocarboxylates (NPEC), nonylphenol (NP), octylphenol (OP), and linear alkylbenzene sulfonates (LAS) in sediment and water samples. The analysis revealed the presence of considerably high concentrations of NPEOs and NP near the points of discharge of industrial and urban wastewaters. Nonylphenol was found in 47% of water samples and in 77% of all sediment samples analyzed. Values for NP ranged from <0.15 to 4.1 microg/L in seawater and from <8 to 1,050 microg/kg in sediments. Levels of AEOs and CDEAs in seawater and marine sediments are reported for the first time. Concentrations of CDEAs in sediment, which were predominated by C11 through C15 homologues, ranged from 30 to 2,700 microg/kg, while in seawater, concentrations found were up to 24 microg/L. The AEOs were found to accumulate in a bottom sediment and they were detected in all analyzed sediment samples in concentrations from 37 to 1,300 microg/kg.

Alkanesulfonic Acids↗
PubMed2002

Endocrine disruptors in sewage treatment plants, receiving river waters, and sediments: integration of chemical analysis and biological effects on feral carp.

Occurrence of alkylphenol ethoxylates or their metabolites (alkylphenols and carboxylated derivatives), as well as natural and synthetic steroids in sewage treatment plant (STP) effluents and in their receiving waters, has been related to biological effects, measured as alterations of plasma vitellogenin (VTG) concentration in natural fish populations. Water composites of STP influents, effluents, sludge, river water, sediment, and feral carps (Cyprinus carpio) were analyzed over a seven-month period in two tributaries of the Llobregat River (NE Spain). Solid-phase extraction/liquid chromatography/mass spectrometry (SPE-LC-MS) analysis revealed concentrations of up to 31 microg/L for nonylphenol ethoxylates (NPEOs), 15 microg/L for nonylphenol (NP), and 35 microg/L for nonylphenoxy carboxylate (NPE1C) in river water downstream of STPs. These compounds were also found to accumulate in river sediment with concentrations ranging from 10 to 820 microg/kg of NPEOs and from 22 to 645 microg/kg for NP. Natural and synthetic estrogens and progestogens also occurred in the water and sediments analyzed but in the ng/L and microg/kg range, respectively. Vitellogenin fluctuated among sites and sampling periods, but it was found to be increased in male carp collected downstream of the main STP. A correlation between endocrine-disrupting compounds (EDCs) in water and sediment and plasma VTG concentration in male carp was observed, especially for alkylphenolic compounds in water and sediment samples (r = 0.83-0.84 for n = 24) and for estriol and estrone in water (r = 0.78 and 0.94 for n = 9 and 8, respectively).

Animals↗