Contamination by Organochlorine Pesticides in the Estuaries of Southeast China* 06 A

Persistent organic pollutants(POPs) such as organochlorine pesticides are of global concern due to their widespread occurrence and persistence. This paper reports recent research studying the distribution and fate of organochlorine pesticides in the Jiulong River, the Minjiang River and the Pearl River estuaries in Southeast China. Eighteen organochlorine pesticides were extracted from water, pore water and sediment samples, followed by analysis by GC-ECD. The results showed that the contamination levels were similar in these three estuaries.The levels of the total organochlorine pesticides in porewater were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. Among the hexachlorocyclohexane (HCH) compounds, β-HCH was found to be the most important isomer. The analysis of 1, 1,1-trichloro-2,2-bis-chlorophenyl-ethane(DDT) and its metabolites showed that 1, 1-dichloro-2[o-chlorophenyl]-2[p-chlorophenyl]-ethylene (DDE) was dominant in the group.Koywords Organochlorine insecticides, DDT, Lindane, Jiulong River Estuary, Minjiang River Estuary, Pearl River Estuary, Water, Sediment     

Occurrence of pharmaceutical metabolites and transformation products in the aquatic environment of the Mediterranean area

The presence of pharmaceutically active substances (PhACs) in aquatic ecosystems is of great concern due to their constant occurrence in different water systems and potential negative effects on the quality of water and living organisms. After consumption, PhACs are excreted as the parent compound, and/or as free or conjugated metabolites, which might finally arrive to surface and ground waters after their incomplete removal (and possible degradation) in the wastewater treatment plants (WWTP). A large amount of data about parent PhACs in water has been reported in the literature in the last decade; however, there is a lack of information about the presence of their metabolites and transformation/degradation products (TPs). Recent publications report that PhACs found in water are only the “top of the iceberg” in relation to the environmental impact associated to the consumption of PhACs. From a scientific-technological point of view, the overall study of PhACs is a challenge and requires to advance with respect to current knowledge and analytical capacities, considering several key aspects, such as the reliable identification and quantification of the compounds, the improvement of the removal efficiency by the WWTPs, the study of their behaviour in the environment (e.g. persistence and biodegradability), and the environmental risk assessment, considering not only the parent PhACs but also their transformation/metabolism products. In this work, it is intended to delve into this problem, presenting a detailed overview on metabolites and TPs of PhACs in environmental waters from the Mediterranean area. Analytical and environmental problems associated to the determination of these compounds are briefly commented, ending the paper with the main conclusions and expected future trends in relation to this field.     

Occurrence patterns of pharmaceuticals in water and wastewater environments

The occurrence of pharmaceuticals and their metabolites and transformation products in the environment is becoming a matter of concern, because these compounds, which may have adverse effects on living organisms, are extensively and increasingly used in human and veterinary medicine and are released continuously into the environment. A variety of pharmaceuticals have been detected in many environmental samples worldwide. Their occurrence has been reported in sewage-treatment-plant effluents, surface water, seawater, groundwater, soil, sediment and fish. This paper provides an overview of recent scientific research on the sources, occurrence, and fate of pharmaceuticals in water and wastewater.     

水环境中胞内外抗生素抗性基因分析的DNA提取方法及污染现状研究进展

新型污染物抗生素抗性基因(Antibiotic resistance genes,ARGs)对公共健康产生了严重威胁,其在水环境中的长期存在和传播引起了广泛重视。胞内与胞外ARGs在水环境中的分布规律和环境行为差异明显,对其污染状况进行研究有助于全面了解水环境中ARGs的传播特性。该文总结了5种常见水样微生物DNA提取方法及其在胞内和胞外ARGs检测研究中的应用状况,比较了污水系统、淡水系统及海水系统等典型水环境中胞内和胞外ARGs的污染状况和迁移传播特性。为进一步探究水环境中ARGs的分布特征与传播机制提供了技术手段及污染现状等基础信息,对控制ARGs在水环境中的传播扩散具有重要意义。     

Occurrence and distribution of selected pharmaceutical compounds on sewage-impacted section of River Acheloos,Western Greece

The occurrence of eight pharmaceutical compounds (PhCs), two metabolites and caffeine was investigated in River Acheloos, located in Western Greece, during a twelve-month monitoring period (March 2007–February 2008). Solid-phase extraction (SPE) was used for the extraction and pre-concentration of the target pollutants and gas chromatography mass spectrometry (GC–MS) for the detection and quantification. Recoveries were determined between 74.0–100.4% for distilled water and 72.6–95.1% for the river water, whereas the relative standard deviation was less than 9.4% for distilled water and 8% for the river water, respectively. The limits of detection ranged between 1–40 ng L^?1. Two pharmaceuticals (paracetamol and carbamazepine), caffeine and the metabolite (salicylic acid), have been detected in all the analysed samples. Maximum concentration levels determined in river samples reached 305 ng L^?1 recorded for paracetamol. The concentrations of target compounds were significantly higher in the samples collected at the sampling station situated after the wastewater treatment plant (WWTP) of Agrinio City compared to the samples collected in upper and lower parts of the river. Seasonal variations were attributed mainly to river flow variations and removal percentages by WWTP. Risk quotient method for median environmental concentrations revealed minimal to median risk with the exception of triclosan, ibuprofen and diclofenac, which presented high risk when maximum environmental concentrations were used.     

Distribution of trace elements in flowing surface waters: Effect of seasons and anthropogenic practices in India

This study reports the distribution of Cr, Ni, Cu and Pb in waters, sediments, macrophytes and fish of the Yamuna River’s patch in Delhi (India). This is one of the most polluted stretches of rivers in the world. Water from this river is used fosr irrigation, industrial and domestic purposes, including drinking water. The effects of season and anthropogenic practices were identified. Almost zero dissolved oxygen and high levels of lead and phosphate indicate the polluted state of the aquatic system. The enrichment factors in sediments (with respect to reference site) vary in the range of 0.60–82.9% (Cr), 1.40–90.5% (Ni), 1.00–85.3% (Cu) and 3.80–86.6% (Pb). The toxic effects due to Ni and Pb could frequently be visible in aquatic life as their values fall above the probable effect level (36 mg Kg^?1 for Ni and 91.3 mg Kg^?1 for Pb). The metal contents in the macrophyte (Eichhornia crassipes) and the fish (Oreochromis niloticus) generally increase in the summer season. Cu and Pb accumulate preferentially in E. crassipes. The fish from these waters is unsuitable for human consumption as the levels of Cr, Cu and Pb are above the recommended limits. Significant spatial variations in parameters of water and sediments were confirmed via one-way analysis of variance. The Pearson’s correlation analysis suggests a common source of some of the metals. Principal component analysis highlighted domestic, and industrial waste and coal-fired thermal power plants as the metal sources. This study might act as a benchmark for other investigations focused on similarly affected surface aquatic systems due to agricultural and industrial activities.     

SPE and HPLC monitoring of 17-β-estradiol in Egyptian aquatic ecosysetms

Solid-phase extraction and HPLC methods are described for monitoring of 17-β-estradiol residues in Egyptian aquatic ecosystems (water, fish, mollusks, sediment, and drinking water) at the Nile River, Suez Canal region, and northeast of Egypt. Molecular imprinted polymer was prepared and used in extraction. High performance liquid chromatography (HPLC) columns used were Supelcosil C₁₈ and Nucleosil C₁₈. The mobile phases used were different combinations of water and acetonitrile. The concentration of 17-β-estradiol in water, aquatic animals, and sediment samples were of 265.13–7988.12 µg/L, 0.503–96.167, and 0.775–11.884 µg/kg, respectively. Marine lake was contained with high levels of 17-β-estradiol (P < 0.05). Similarly, the Nile River downstream showed high levels of 17-β-estradiol. The detected concentrations in mollusks were significantly higher than those detected in fish. Tilapia fish did not show 17-β-estradiol. Contrarily, low concentrations were detected in the rivulet streams supplied by the Nile River. Besides, 17-β-estradiol was also detected in the sediments at low levels. Detection of 17-β-estradiol in the Egyptian ecosystems attracted attention toward heavy reliance on some esterogenic medicinal products in Egypt. The monitoring of 17-β-estradiol in other water bodies was recommended. Besides, the development of methodologies of bioremediation to eliminate 17-β-estradiol from the Egyptian and other water resources of the world was also suggested.     

Recently developed GC/MS and LC/MS methods for determining NSAIDs in water samples

Pharmaceuticals have become major targets in environmental chemistry due to their presence in aquatic environments (following incomplete removal in wastewater treatment or point-source contaminations), threat to drinking water sources and concern about their possible effects to wildlife and humans. Recently several methods have been developed for the determination of drugs and their metabolites in the lower nanogram per litre range, most of them using solid-phase extraction (SPE) or solid-phase microextraction (SPME), derivatisation and finally gas chromatography mass spectrometry (GC-MS), gas chromatography tandem mass spectrometry (GC-MS/MS) and liquid chromatography electrospray tandem mass spectrometry (LC-ES/MS/MS). Due to the elevated polarity of non-steroidal anti-inflamatory drugs (NSAIDs), analytical techniques based on either liquid chromatography coupled to mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS) after a previous derivatisation step are essential. The most advanced aspects of current GC-MS, GC-MS/MS and LC-MS/MS methodologies for NSAID analysis are presented.     

Levels, trends and risk assessment of arsenic pollution in Yangzonghai Lake, Yunnan Province, China

The arsenic contamination accident in Yangzonghai Lake, Yunnan has been of wide concern. In order to investigate the arsenic distribution and concentration trends after the accident, samples including lake water, sediments, soil, aquatic organisms and crops were collected in November 2008, as well as in February, May and September 2009. The average arsenic concentrations (arithmetic average) in lake water in the four sampling events were 176.9, 147.3, 159.3, and 161.1 μg/L, while those in the sediments were 32.87, 62.41, 62.99, and 46.96 μg/g, respectively. The highest content of total arsenic in soil in the vicinity of Yangzonghai was 23.33 μg/g, which was below the limits of the relevant national standard. The total arsenic levels in most aquatic plants were in the range of 100–200 μg/g, with Vallisneria natans (Lour.) Hara having the highest concentration of ～300 μg/g. The arsenic levels of fish and shrimps were in the range of 1.52–11.4 μg/g (dry weight).     

Atrazine and its Metabolites as Indicators of Stream-aquifer Interaction in Kansas,USA

Abstract

A survey of atrazine and its metabolites in Kansas ground water indicated that ground-water quality was impacted by stream-aquifer interaction between rivers in the Kansas River basin and their adjacent alluvial aquifers. Atrazine was detected in 19 of the 78 samples. The most common metabolite, deethylatrazine, was detected in 25 samples, 18 of which also had atrazine. The deethylatrazine/atrazine ratio (DAR) of < 1.0 indicates rapid movement of agricultural chemicals to ground water. In this study, 12 of 18 samples had DAR values < 1.0, suggesting rapid recharge to the aquifers. Hydroxyatrazine is seldom detected in ground water. In this study hydroxyatrazine was detected primarily in wells sited in alluvium of rivers. These rivers contain atrazine in varying concentrations. Results of the study suggest that stream-aquifer interaction is a process contributing to the presence of both atrazine and its metabolites in ground water in these areas.     

Pharmaceutical residues in environmental waters and wastewater: current state of knowledge and future research

Pollution from pharmaceuticals in the aquatic environment is now recognized as an environmental concern in many countries. This has led to the creation of an extensive area of research, including among others: their chemical identification and quantification; elucidation of transformation pathways when present in wastewater-treatment plants or in environmental matrices; assessment of their potential biological effects; and development and application of advanced treatment processes for their removal and/or mineralization. Pharmaceuticals are a unique category of pollutants, because of their special characteristics, and their behavior and fate cannot be simulated with other chemical organic contaminants. Over the last decade the scientific community has embraced research in this specific field and the outcome has been immense. This was facilitated by advances in chromatographic techniques and relevant biological assays. Despite this, a number of unanswered questions exist and still there is much room for development and work towards a more solid understanding of the actual consequences of the release of pharmaceuticals in the environment. This review tries to present part of the knowledge that is currently available with regard to the occurrence of pharmaceutical residues in aquatic matrices, the progress made during the last several years on identification of such compounds down to trace levels, and of new, previously unidentified, pharmaceuticals such as illicit drugs, metabolites, and photo-products. It also tries to discuss the main recent findings in respect of the capacity of various treatment technologies to remove these contaminants and to highlight some of the adverse effects that may be related to their ubiquitous existence. Finally, socioeconomic measures that may be able to hinder the introduction of such compounds into the environment are briefly discussed.     

Hair analysis as a new tool to monitor adherence to long-term therapy to statins

Statins are cholesterol-lowering medications which are widely prescribed as first-line treatment for hyperlipidemia, against high blood cholesterol aimed at reducing the risk of atherosclerotic diseases. Notwithstanding their undoubted efficacy, the needed long-term treatment with these drugs is characterized by a high percentage of dropout. Consequently, an effective tool to verify the patients’ compliance to statin therapy is needed. In this context, the analysis for drugs and drug metabolites in the hair may represent an almost ideal tool because, according to a sound body of forensic toxicological literature, concentrations in the hair matrix reflect the chronic intake of drugs and pharmaceuticals. In this light, in the present study, a novel, specific and sensitive ultra-performance liquid chromatography–tandem mass spectrometry method has been developed to determine six statins and their metabolites (namely atorvastatin, (p)α-OH-atorvastatin-lactone, (o)α-OH-atorvastatin-lactone, rosuvastatin, N-desmethyl rosuvastatin and pravastatin) in human hair. After optimization, the method was successfully validated in terms of selectivity, linearity, sensitivity, precision, accuracy, stability and matrix effect. Moreover, the practical applicability of this method for verifying adherence to statin therapy was assessed by testing samples of hair collected from subjects under long-term therapy with statins.     

LC/MS study of the UV filter hexyl 2‐[4‐(diethylamino)‐2‐hydroxybenzoyl]‐benzoate (DHHB) aquatic chlorination with sodium hypochlorite

The fate of modern personal care products in the environment is becoming a matter of increasing concern because of the growing production and assortment of these compounds. More and more chemicals of this class are treated as emerging contaminants. Transformation of commercially available products in the environment may result in the formation of a wide array of their metabolites. Personal care products in swimming pools and in drinking water reservoirs may undergo oxidation or chlorination. There is much data on the formation of more toxic metabolites from original low toxicity commercial products. Therefore, reliable identification of all possible transformation products and a thorough study of their physicochemical and biological properties are of high priority. The present study deals with the identification of the products of the aquatic chlorination of the hexyl 2‐[4‐(diethylamino)‐2‐hydroxybenzoyl]‐benzoate ultraviolet filter. High‐performance liquid chromatography/mass spectrometry (HPLC/MS) and HPLC/MS/MS with accurate mass measurements were used for this purpose. As a result, three chlorinated transformation products were identified. Copyright © 2013 John Wiley & Sons, Ltd.     

Rapid monitoring and sensitive determination of DDT and its metabolites in water sample using solid-phase extraction followed by ion mobility spectrometry

Dichlorodiphenyl trichloroethane (DDT) as an organochlorine compound has been globally used as a pesticide for controlling soil-dwelling insects and treating diseases such as malaria and typhus. The degradation products of DDT and its metabolites have also negative effects on the environment. The present study has investigated the determination of DDT and its metabolites in water sample using ion mobility spectrometry (IMS) as a rapid and sensitive detection technique. For this purpose, DDT and its metabolites were extracted using reverse phase solid-phase extraction (SPE) from water samples. The samples were then recovered by eluting with methanol and finally, quantified using the corona discharge IMS technique. Injection and oven temperatures and the effect of dopant were optimized as experimental parameters influencing both detection and determination efficiencies. Degradation of DDT in IMS drift tube was studied and reduced mobility values of DDT and its metabolites were calculated. The developed method was validated using water sample to obtain good results for the determination of DDT at low levels (1 ng ml^?1) while spiked recoveries were obtained to be between 95.0–96.7%. The proposed method based on IMS proved to be a simple, inexpensive, rapid and sensitive procedure for the fast monitoring and determination of DDT and its main metabolites in water sample.     

Liquid chromatographic determination of per- and polyfluoroalkyl substances in environmental river water samples

Contaminants of emerging concern (CECs) such as per- and polyfluoroalkyl substances (PFAS) have attracted significant interest from researchers, policymakers, and water treatment facilities. This is because PFAS are highly persistent in the environment and tend to be bio-accumulative thus causing adverse effects on terrestrial and aquatic life. Therefore, there is a need for simpler and fast methods for the determination of PFAS in water sources. This work aims at the application of dispersive magnetic solid-phase extraction (DMSPE) for the enrichment of PFAS in various surface water samples. Magnetic Fe₃O₄@MIL-101 (Cr) was used as an adsorbent in MSPE. Fe₃O₄@MIL-101(Cr) was used for the first time for the preconcentration and extraction of PFAS in various river water samples. The concentrations of target analytes in water samples were determined using high performance liquid chromatography-diode array detector and ultra-high performance liquid chromatography-tandem mass spectrometry analysis. The combination of optimized DMSPE with HPLC-DAD and UHPLC-MS/MS provided wide linear range (1–5000 ng/L and 0.05–2000 ng/L, low limits of detection (0.3–0.66 ng/L and 0.011–0.04 ng/L) and limits of quantification (1.0–2.2 ng/L and 0.04–0.12 ng/L). Moreover, acceptable intraday and interday precision based on the relative standard deviation (RSD) lower than 5% were obtained. The developed method showed remarkable practicability for the analysis of ultra-trace PFAS in water samples.     

Investigation of interaction strategies between pyrazolone dyes and poly(acrylamide-co-acrylic acid)

The removal of dyes from waste water before their discharge into aquatic ecosystems is of substantial concern. Amongst functional macromolecules, the combination of polymers with dyes is a research field of enormous potential with regard to high-performance materials. The present study investigates interactions strategies between P(AM-co-AA) polymer with pyrazolone azo dyes in water as green solvent. These interactions were confirmed by FTIR spectroscopy, Ultra-visible spectroscopy, EDAX analysis, and FE-SEM analysis. Polymer P(AM-co-AA) has porous structure in which dyes present in the water get absorb hence it is use to remove pyrazolone dyes from water.

     

Gas–liquid chromatography–tandem mass spectrometry methodology for the quantitation of estrogenic contaminants in bile of fish exposed to wastewater treatment works effluents and from wild populations

Fish can be exposed to a complex mixture of chemical contaminants arising from the exposure to wastewater treatment works (WwTWs) effluents. Some of these contaminants are estrogenic and have been associated with feminisation of male fish and the presence of populations containing intersex individuals. However the detection of trace levels (ng/L) of estrogenic chemicals surface waters can be difficult and does not give information on the exposure of aquatic organisms to these contaminants. In this study we assessed whether the analysis of estrogenic substances that bioconcentrate in fish bile can be used to detect the exposure of fish to feminising contaminants in receiving waters and effluents, and thus facilitate their monitoring of these substances in aquatic environments. Estrogenic metabolites in bile were deconjugated using enzymatic hydrolysis and partially purified by solid phase extraction. Steroidal and xenoestrogens were derivatized to their trimethylsilyl ethers and quantified by gas–liquid chromatography–mass spectrometry (GC–MS/MS) using multiple reaction monitoring. The method was validated using spiked bile samples from immature female rainbow trout (Oncorhynchus mykiss) as well as bile from sexually mature roach (Rutilus rutilus) that had been exposed to either tap water or an undiluted estrogenic effluent for 10 days or captured from a river site downstream of a WwTWs effluent discharge. The mean recovery of target analytes from spiked bile was between 86 and 99% and the limit of detection was between 0.1 and 0.7 ng/mL bile for bisphenol A (BPA), 17β-estradiol (E2), estrone (E1) and 17α-ethinylestradiol (EE2), and 11, 60 and 327 ng/mL bile for branched nonyl chain isomeric mixtures of 4-nonylphenolethoxylate (NP1EO), 4-nonylphenol (NP) and 4-nonylphenoldiethoxylate (NP2EO), respectively. All target analytes were detected in bile from roach exposed directly to a WwTWs effluent, with concentrations between 6–13 μg/mL bile for NP, 18–21 μg/mL for NP1EO, 75–135 μg/mL for NP2EO, 0.7–2.5 μg/mL for BPA, E2 and E1 and 17–29 ng/mL for EE2. With the exception of NP2EO, all analytes were detected in at least 2 out of the 5 fish sampled from the River Thames. BPA and NP1EO were detected in all three reference fish held in tap water indicating possible contamination from laboratory plastics. The work shows that analysis of 20–100 μL quantities of bile could be a useful approach in detecting exposure to mixtures of estrogenic contaminants taken up by fish from WwTW effluents and has the potential for monitoring the efficacy of remediation strategies that may be adopted for reduction of these endocrine disrupting chemicals in the aquatic environment.     

Drugs of abuse and their metabolites in waste and surface waters by liquid chromatography-tandem mass spectrometry

A solid‐phase extraction and liquid chromatography‐tandem mass spectrometry (SPE/LC‐MS‐MS) method was developed and validated for the simultaneous determination of nicotine, five drugs of abuse (morphine, cocaine, codeine, methadone, and 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine) and four metabolites (dihydrocodeine, 6‐acetylmorphine, 11‐nor‐carboxy‐Δ⁹‐tetrahydrocannabinol, and benzoylecgonine) in water samples. A Fused‐Core? particle column was used as an alternative to sub‐2‐μm particles in chromatographic separations to work with low backpressures and high efficiencies in short analysis times. Drugs were extracted from waste and surface water with SPE using Oasis MCX cartridges. Electrospray (ESI) in positive and negative mode and tandem MS selected reaction monitoring mode were used for identification and quantification. Calibration by linear regression analysis with deuterated internal standards was used to compensate the matrix effects. Limits of detection were found as low as 0.5–1 ng/L (surface water) and 1–50 ng/L (wastewater). The method was applied to the analysis of different kinds of samples. Wastewater from a sewage treatment plant was collected from three sampling points (after primary, secondary, and tertiary treatments) for a week. The analysis of the samples revealed a significant presence of these drugs in samples from primary treatments, where maximum concentrations of nicotine (1105 ng/L) and benzoylecgonine (3336 ng/L) were found. Most of the compounds showed values between 相似文献   

Organophosphate esters in water,suspended particulate matter (SPM) and sediments of the Minjiang River,China

As organic pollutants of emerging concern, organophosphate esters (OPEs) have shown toxicity to organisms after entering the water environment. However, research on OPEs in freshwater in Southwest China is very limited. The levels, distribution and partitioning behavior of OPEs in the Minjiang River and their influencing factors is still unknown. In this study, six OPEs, tri-n-butyl phosphate (TnBP), tri(2-chloroethyl)-phosphate (TCEP), trichloropropyl phosphate (TCPP), triphenyl phosphate (TPhP), tributoxyethyl phosphate (TBEP), and tris(2-ethylhexyl)-phosphate (TEHP), were determined in surface water, suspended particle matter (SPM) and sediments of the Minjiang River. The results showed that the average concentrations of Σ₆OPEs in surface water, SPM and sediments of the Minjiang River were 199.32 ± 124.95 ng/L, 38463.79 ± 45641.89 ng/g dry weight (dw) and 76.45 ± 28.00 ng/g dw, respectively. High concentrations of OPEs were detected in SPM samples, indicating that more attention should be paid to pollution in SPM. It is worth noting that the variation trend of OPEs in SPM was almost opposite to that in water but basically similar to that in sediment. The proportions of alkyl OPEs in Σ₆OPEs increased from surface water to SPM and sediments. Alkyl OPEs were the main pollutants in SPM (10.44%–80.88% of Σ₆OPEs, mean of 54.52%) and sediments (59.08%–81.30% of Σ₆OPEs, mean of 68.91%), whereas chlorinated OPEs were the most abundant components in surface water (43.16%–75.99% of Σ₆OPEs, mean of 55.50%). The water-sediment partition coefficient (logK_OC) of OPEs was 4.97–7.58, while the water-SPM partition coefficient was 6.71–10.00. No significant correlations were found between logK_OW and logK_OC. K_OW was not the main factor affecting the distribution of OPEs in the Minjiang River, China.     

Retrospective LC-QTOF-MS analysis searching for pharmaceutical metabolites in urban wastewater

The presence of pharmaceuticals in the environment is a matter of major concern because of their wide consumption and their potential negative effect on the water quality and living organisms. After human and/or veterinary consumption, pharmaceuticals can be excreted in unchanged form as the parent compound and/or as free or conjugated metabolites. These compounds seem not to be completely removed during wastewater treatments and might finally arrive to surface and ground waters. Consequently, both parent pharmaceuticals and metabolites are target analytes to be considered in analytical methodologies. The satisfactory sensitivity in full-acquisition mode, high-resolution, exact mass measurements and MS/MS capabilities of hybrid quadrupole time-of-flight (QTOF) mass spectrometry make of this technique a powerful analytical tool for the identification of organic contaminants. In this study, the use of QTOF-MS with the aid of specialised processing-data application managers has allowed the retrospective analysis of pharmaceuticals metabolites in urban wastewater without the need for additional injection of sample extracts. Around 160 metabolites have been investigated in wastewater samples previously analysed only for parent compounds using LC-QTOF under MS(E) mode (simultaneous recording of two acquisition functions, at low and high collision energy). The retrospective analysis was applied to search for pharmaceutical metabolites in parent-positive effluent wastewaters from the Spanish Mediterranean region. Five metabolites, such as clopidogrel carboxylic acid or N-desmethyl clarithromycin, were identified in the samples.