Thermodynamic and kinetic studies of As(V) removal from water by zirconium oxide-coated marine sand

Arsenic contamination of groundwater is a major threat to human beings globally. Among various methods available for arsenic removal, adsorption is fast, inexpensive, selective, accurate, reproducible and eco-friendly in nature. The present paper describes removal of arsenate from water on zirconium oxide-coated sand (novel adsorbent). In the present work, zirconium oxide-coated sand was prepared and characterised by infrared and X-ray diffraction techniques. Batch experiments were performed to optimise different adsorption parameters such as initial arsenate concentration (100–1,000 μg/L), dose (1–8 g/L), pH of the solution (2–14), contact time (15–150 min.), and temperature (20, 30, 35 and 40 °C). The experimental data were analysed by Langmuir, Freundlich, Temkin and Dubinin–Radushkevich isotherm models. Furthermore, thermodynamic and kinetic parameters were evaluated to know the mode of adsorption between ZrOCMS and As(V). The maximum removal of arsenic, 97 %, was achieved at initial arsenic concentration of 200 μg/L, after 75 min at dosage of 5.0 g/L, pH?7.0 and 27?±?2 °C. For 600 μg/L concentration, the maximum Langmuir monolayer adsorption capacity was found to be 270 μg/g at 35 °C. Kinetic modelling data indicated that adsorption process followed pseudo-second-order kinetics. The mechanism is controlled by liquid film diffusion model. Thermodynamic parameter, ΔH°, was ?57.782, while the values of ΔG° were ?9.460, ?12.183, ?13.343 and ?13.905 kJ/mol at 20, 30, 35 and 40 °C, respectively, suggesting exothermic and spontaneous nature of the process. The change in entropy, ΔS°?=??0.23 kJ/mol indicated that the entropy decreased due to adsorption of arsenate ion onto the solid adsorbent. The results indicated that the reported zirconium oxide-coated marine sand (ZrOCMS) was good adsorbent with 97 % removal capacity at 200 μg/L concentration. It is interesting to note that the permissible limit of arsenic as per World Health Organization is 10 μg/L, and in real situation, this low concentration can be achieved through this adsorbent. Besides, the adsorption capacity showed that this adsorbent may be used for the removal of arsenic from any natural water resource.     

Biotic and abiotic transformations of methyl tertiary butyl ether (MTBE)

Background Methyl tertiary butyl ether (MTBE) is a fuel additive which is used all over the world. In recent years it has often been found in groundwater, mainly in the USA, but also in Europe. Although MTBE seems to be a minor toxic, it affects the taste and odour of water at concentrations of < 30 μg/L. Although MTBE is often a recalcitrant compound, it is known that many ethers can be degraded by abiotic means. The aim of this study was to examine biotic and abiotic transformations of MTBE with respect to the particular conditions of a contaminated site (former refinery) in Leuna, Germany. Methods Groundwater samples from wells of a contaminated site were used for aerobic and anaerobic degradation experiments. The abiotic degradation experiment (hydrolysis) was conducted employing an ion-exchange resin and MTBE solutions in distilled water. MTBE, tertiary butyl formate (TBF) and tertiary butyl alcohol (TBA) were measured by a gas chromatograph with flame ionisation detector (FID). Aldehydes and organic acids were respectively analysed by a gas chromatograph with electron capture detector (ECD) and high-performance ion chromatography (HPIC). Results and Discussion Under aerobic conditions, MTBE was degraded in laboratory experiments. Only 4 of a total of 30 anaerobic experiments exhibited degradation, and the process was very slow. In no cases were metabolites detected, but a few degradation products (TBF, TBA and formic acid) were found on the site, possibly due to the lower temperatures in groundwater. The abiotic degradation of MTBE with an ion-exchange resin as a catalyst at pH 3.5 was much faster than hydrolysis in diluted hydrochloric acid (pH 1.0). Conclusion Although the aerobic degradation of MTBE in the environment seems to be possible, the specific conditions responsible are widely unknown. Successful aerobic degradation only seems to take place if there is a lack of other utilisable compounds. However, MTBE is often accompanied by other fuel compounds on contaminated sites and anaerobic conditions prevail. MTBE is often recalcitrant under anaerobic conditions, at least in the presence of other carbon sources. The abiotic hydrolysis of MTBE seems to be of secondary importance (on site), but it might be possible to enhance it with catalysts. Recommendation and Outlook MTBE only seems to be recalcitrant under particular conditions. In some cases, the degradation of MTBE on contaminated sites could be supported by oxygen. Enhanced hydrolysis could also be an alternative. - * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August to 1 September 2004, Bordeaux, France.     

Particulates and Metallic Elements Monitoring at Two Sampling Sites (Harbor,Airport) in Taiwan

This study characterized the dry deposition flux and dry deposition velocity (Vd) of metallic elements attached on particulate matter. Specifically, large particles (>10 μm), coarse particles (10 μm～2.5 μm), and fine particles (<2.5 μm) were studied at the Gong Ming Junior High School (Taichung Airport) and Taichung Harbor sampling sites in central Taiwan. Ambient air samples were collected to determine total suspended particulate matter (TSP), dry deposition plate (DDP), Vd, coarse particulate matter (PM_2.5–10) and fine particulate matter (PM_2.5), and metallic elements concentrations at the Airport and Taichung Harbor sites between June 17, 2013, and November 14, 2013. The results revealed that the average TSP, DDP, Vd, PM_2.5–10, and PM_2.5 particulate at the Airport were 54.55 (μg/m³), 902.25 (μg/m²-min), 17.11 (m/sec), 0.003 (μg/m³), and 0.010 (μg/m³), respectively; while these values at Taichung Harbor were 63.66 (μg/m³), 539.69 (μg/m²-min), 9.94 (m/sec), 0.003 (μg/m³), and 0.014 (μg/m³), respectively. In addition, the results showed that the average Cu and Pb concentrations were higher than Cr, Ni, and Cd for both the airport and harbor sampling sites. Furthermore, Cr, N, Cu, Cd, and Pb had the highest average concentrations versus those reported for other study areas, with one exception: The results obtained in Kacanik, Kosovo, during 2005. The average metallic elements concentrations order was Cu > Pb > Cr > Ni > Cd.     

Determination of antibiotics in sewage from hospitals, nursery and slaughter house, wastewater treatment plant and source water in Chongqing region of Three Gorge Reservoir in China

Sewage samples from 4 hospitals, 1 nursery, 1 slaughter house, 1 wastewater treatment plant and 5 source water samples of Chongqing region of Three Gorge Reservoir were analyzed for macrolide, lincosamide, trimethoprim, fluorouinolone, sulfonamide and tetracycline antibiotics by online solid-phase extraction and liquid chromatography-tandem mass spectrometry. Results showed that the concentration of ofloxacin (OFX) in hospital was the highest among all water environments ranged from 1.660 μg/L to 4.240 μg/L and norfloxacin (NOR, 0.136-1.620 μg/L), ciproflaxacin (CIP, ranged from 0.011 μg/L to 0.136 μg/L), trimethoprim (TMP, 0.061-0.174 μg/L) were commonly detected. Removal range of antibiotics in the wastewater treatment plant was 18-100% and the removal ratio of tylosin, oxytetracycline and tetracycline were 100%. Relatively higher removal efficiencies were observed for tylosin (TYL), oxytetracycline (OXY) and tetracycline (TET)(100%), while lower removal efficiencies were observed for Trimethoprim (TMP, 1%), Epi-iso-chlorotetracycline (EICIC, 18%) and Erythromycin-H₂O (ERY-H₂O, 24%). Antibiotics were removed more efficiently in primary treatment compared with those in secondary treatment.     

Sources of Volatile Organic Compounds in a University Building

A total of 34 volatile organic compounds (VOCs) were measured in the indoor of laboratories, offices and classrooms of the Chemical Engineering Department of Hacettepe University in Ankara in 2 week-day passive sampling campaigns. The average concentrations ranged from 0.77 to 265 μg m^?3 at the different indoor sites, with the most abundant VOC found to be toluene (119.6 μg m^?3), followed by styrene (21.24 μg m^?3), 2-ethyltoluene (17.11 μg m^?3), n-hexane (10.21 μg m^?3) and benzene (9.42 μg m^?3). According to the factor analysis, the evaporation of solvents used in the laboratories was found to be the dominant source.     

Trace metals in Ganges soft-shell turtle (Aspideretes gangeticus) from two barrage: Baloki and Rasul, Pakistan

The concentration of nine metals was measured in liver, kidney, heart, muscle, plastron, and carapace of Aspideretes gangeticus from Rasul and Baloki barrages, Pakistan. The results indicated that metal concentration were significant different among tissues of Ganges soft-shell turtles. However, higher concentrations of Co (5.12 μg/g) and Ni (1.67 μg/g) in liver, Cd (0.41 μg/g) in heart, Fe (267.45 μg/g), Cd (2.12 μg/g) and Mn (2.47 μg/g) in kidney, Cd (0.23 μg/g), Cu (2.57 μg/g), Fe (370.25 μg/g), Mn (5.56 μg/g), and Pb (8.23 μg/g) in muscle of A. gangeticus were recorded at Baloki barrage than Rasul barrage. Whereas mean concentrations of Pb (3.33 μg/g) in liver, Co (1.63 μg/g), Cu (11.32 μg/g), Pb (4.8 μg/g) and Zn (144.69 μg/g) in heart, Co (4.12 μg/g) in muscle, Ni (1.31 μg/g), Pb (2.18 μg/g), and Zn (9.78 μg/g) in carapace were recorded higher at Rasul barrage than Baloki barrage. The metals followed the trend Fe > Zn > Ni > Cu > Mn > Pb > Cr > Co > Cd. Metals of toxicological concern such as Cr, Pb, and Cd were at that level which can cause harmful effects to turtles. The results provide baseline data of heavy metals on freshwater turtle species of Pakistan.     

Health risks of environmental exposure to metals and herbicides in the Pardo River,Brazil

Mixture of metals and herbicides in rivers may pose relevant risks for the health of surrounding communities. Humans may be exposed to river pollution through intake of contaminated water and fish, as well as irrigated agricultural products. The aim of this study was to assess the human health risks of environmental exposure to metals and herbicides through water and fish intake in the Pardo River. Metals (Al, As, Be, Cd, Cr, Cu, Pb, Mn, Hg, Ni, Tl, Sn, V, and Zn) were analyzed in river water and in edible fish. Herbicides (ametryn, atrazine, diuron, hexazinone, simazine, and tebuthiuron) were analyzed in river water. Seasonal variances were also studied. Aluminum, Cd, Cu, Mn, Pb, and Zn levels in river water were higher than the USEPA benchmarks. Non-carcinogenic risks due to pollutants mixture exposure were above the limit, and carcinogenic risks of As exposure were >10^?6 in the sampling points during the rainy season. Metal levels in fish were lower than the Brazilian legislation and do not pose a threat to public health. Herbicides were detected in four sampling points, with atrazine concentrations (range 0.16–0.32 μg/L) below the Brazilian standard (2.0 μg/L), but above the European Union standard (0.1 μg/L). Considering the water supply needs of cities located in the Pardo River Basin and the persistence of metals and herbicides, the present study indicated that there was a seasonal influence on non-carcinogenic and carcinogenic risks to human health, especially in the rainy season. Studies for water treatment plants implantation should consider the risks of exposure to persistent substances, in order to protect the population.     

Acute toxicity of copper,lead, cadmium,and zinc to early life stages of white sturgeon (Acipenser transmontanus) in laboratory and Columbia River water

Populations of white sturgeon (Acipenser transmontanus) are in decline in North America. This is attributed, primarily, to poor recruitment, and white sturgeon are listed as threatened or endangered in several parts of British Columbia, Canada, and the United States. In the Columbia River, effects of metals have been hypothesized as possible contributing factors. Previous work has demonstrated that early life stage white sturgeon are particularly sensitive to certain metals, and concerns over the level of protectiveness of water quality standards are justified. Here we report results from acute (96-h) toxicity tests for copper (Cu), cadmium (Cd), zinc (Zn), and lead (Pb) from parallel studies that were conducted in laboratory water and in the field with Columbia River water. Water effect ratios (WERs) and sensitivity parameters (i.e., median lethal accumulations, or LA50s) were calculated to assess relative bioavailability of these metals in Columbia River water compared to laboratory water, and to elucidate possible differences in sensitivity of early life stage white sturgeon to the same concentrations of metals when tested in the different water sources. For Cu and Pb, white sturgeon toxicity tests were initiated at two life stages, 8 and 40 days post-hatch (dph), and median lethal concentrations (LC50s) ranged between 9–25 μg Cu/L and 177–1,556 μg Pb/L. LC50s for 8 dph white sturgeon exposed to Cd in laboratory water and river water were 14.5 and 72 μg/L, respectively. Exposure of 8 dph white sturgeon to Zn in laboratory and river water resulted in LC50s of 150 and 625 μg/L, respectively. Threshold concentrations were consistently less in laboratory water compared with river water, and as a result, WERs were greater than 1 in all cases. In addition, LA50s were consistently greater in river water exposures compared with laboratory exposures in all paired tests. These results, in combination with results from the biotic ligand model, suggest that the observed differences in toxicity between river water exposures and laboratory water exposures were not entirely due to differences in water quality and metal bioavailability but rather in combination with differences in fish sensitivity. It is hypothesized that differences in concentrations of calcium in the different water sources might have resulted in differences in acquired sensitivity of sturgeon to metals. Canadian water quality guidelines, US national criteria for the protection of aquatic life, and water quality criteria for the state of Washington were less than LC50 values for all metals and life stages tested in laboratory and Columbia River water. With the exception, however, that 40 dph white sturgeon exposed to Cu in laboratory water resulted in threshold values that bordered US national criteria and criteria for the state of Washington.     

Presence of microbial and chemical source tracking markers in roof-harvested rainwater and catchment systems for the detection of fecal contamination

Microbial source tracking (MST) and chemical source tracking (CST) markers were utilized to identify fecal contamination in harvested rainwater and gutter debris samples. Throughout the sampling period, Bacteroides HF183 was detected in 57.5 % of the tank water samples and 95 % of the gutter debris samples, while adenovirus was detected in 42.5 and 52.5 % of the tank water and gutter debris samples, respectively. Human adenovirus was then detected at levels ranging from below the detection limit to 316 and 1253 genome copies/μL in the tank water and debris samples, respectively. Results for the CST markers showed that salicylic acid (average 4.62 μg/L) was the most prevalent marker (100 %) in the gutter debris samples, caffeine (average 18.0 μg/L) was the most prevalent in the tank water samples (100 %) and acetaminophen was detected sporadically throughout the study period. Bacteroides HF183 and salicylic acid (95 %) and Bacteroides HF183 and caffeine (80 %) yielded high concurrence frequencies in the gutter debris samples. In addition, the highest concurrence frequency in the tank water samples was observed for Bacteroides HF183 and caffeine (60 %). The current study thus indicates that Bacteroides HF183, salicylic acid and caffeine may potentially be applied as source tracking markers in rainwater catchment systems in order to supplement fecal indicator analyses.     

Survey of cyanobacterial toxins in Czech water reservoirs—the first observation of neurotoxic saxitoxins

The environmental occurrence and concentrations of cyanobacterial toxins (cyanotoxins) were investigated in the Czech Republic. Concentrations of microcystins (MCs), cylindrospermopsin (CYN) or saxitoxins (STXs) were determined immunochemically by ELISA assays in 30 water samples collected from the surface layers of 19 reservoirs during the summer season of 2010. MCs were detected in 18 reservoirs and 83 % of samples, with median and maximal concentration being 1.5 and 18.6 μg/L, respectively. The high frequency of MC occurrence coincided with prevalence of cyanobacterium Microcystis sp., which was detected in 87 % samples, followed by Dolichospermum (Anabaena) sp. observed in 33 % samples. CYN was detected by ELISA only in one sample at a concentration of 1.2 μg/L. STXs presence was indicated for the first time in Czech water reservoirs when the toxins were found at low concentrations (0.03–0.04 μg/L) in two samples (7 %) collected from two different reservoirs, where STXs co-occurred with MCs and eventually also with CYN. In both STX-positive samples, the phytoplankton community was dominated by Microcystis sp., but Dolichospermum sp. and/or Aphanizomenon sp. were also present as putative producers of STX and/or CYN. Cyanotoxins commonly occurred in Czech water reservoirs, and MCs frequently at concentrations possibly associated with human health risks. MCs were the most prevalent and abundant cyanotoxins, but also other cyanotoxins were detected, though sporadically. Further research and regulatory monitoring of cyanotoxins other than MCs is therefore required.     

Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in Sediment Cores of Selected Creeks in Delta State,Nigeria

The spatial and seasonal distribution and concentrations of polycyclic aromatic hydrocarbons (PAHs) were investigated in core sediments of Ubeji, Ifie, and Egbokodo creeks in the Niger Delta, Nigeria. A total of 222 core sediment samples were collected during the wet season (August 2010) and the dry season (January 2011). The samples were dried, Soxhlet extracted, fractionated, and injected into a gas chromatograph with flame ionization detector (GC-FID). The concentrations of PAHs ranged from not detected to 2,654 μg/kg (wet season) and not detected to 3,513 μg/kg (dry season). In general, the concentrations of PAHs for a number of stations in this study are comparable to sites with high anthropogenic activities in the Niger Delta. The toxicity risk assessment based on the total BaP equivalent quotient of the seven carcinogenic PAHs (BaA, Chry, BbF, BkF, BaP, DBA, and Iper) was 97.416 μg/kg and did not exceed the method B cleanup level for benzo(a)pyrene (137 μg/kg), according to toxic equivalency factors, which implied that PAHs in sediments of the present study currently have minimal adverse effects. This study provided information on the concentrations and profiles of PAHs sediment cores, which is useful for source diagnosis, environmental quality management, contamination history, and environmental forensic studies.     

Simultaneous determination of eight metabolites of organophosphate and pyrethroid pesticides in urine

A simultaneous method for quantifying eight metabolites of organophosphate pesticides and pyrethroid pesticides in urine samples has been established. The analytes were extracted using liquid–liquid extraction coupled with WCX solid phase extraction (SPE) cartridges. Eight metabolites were chemically derivatized before analysis using gas chromatography–tandem mass spectrometry (GC–MS–MS). The separation was performed on a HP-5MS capillary column (30 m × 0.25 mm × 0.25 µm) with temperature programming. The detection was performed under electro-spray ionization (ESI) in multiple reaction monitoring (MRM) mode. An internal standard method was used. The extraction solvent, types of SPE cartridges and eluents were optimized by comparing the sample recoveries under different conditions. The results showed that the calibration curves of the five organophosphorus pesticides metabolites were linear in the range of 0.2–200 μg/L (r² ≥ 0.992) and that of the three pyrethroid pesticides metabolites were linear in the range of 0.025–250 μg/L (r² ≥ 0.991). The limits of detection (LODs, S/N ≥ 3) and the limits of quantification (LOQs, S/N ≥ 10) of the eight metabolites were 0.008–0.833 μg/L and 0.25–2.5 μg/L, respectively. The recoveries of the eight metabolites ranged from 54.08% to 82.49%. This efficient, stable, and cost-effective method is adequate to handle the large number of samples required for surveying the exposure level of organophosphorus and pyrethroid pesticides in the general population.     

Residues of organochlorine and organophosphorus pesticides in sugarcane crop soils and river water

The presence of residual organochlorine and organophosphorus pesticides was evaluated at different periods of sugarcane cultivation in agricultural soil and water samples from the town of Tlaltizapan, which is located in the state of Morelos in Mexico, to determine the presence and persistence of these compounds and their possible effects on the region. The compounds p,p′-DDE, p,p′-DDD (metabolites of p,p′-DDT), γ-HCH and heptachlor were found in more of 95% of the sampling zones in the three monitoring periods performed along 2 years. The highest concentration detected (129.6 μg/kg _{dry soil}) was for α-HCH, but its frequency of detection was ～5%. The low detection frequency of α-HCH and the high concentration values of γ-HCH indicate the repeated use of technical-grade HCH and Lindane (γ-HCH) in the region. Among the organophosphorus pesticides, ethyl parathion was the compound with the highest soil concentration, at ～2000 μg/kg_{dry soil}, during the initial monitoring. However, this compound was detected in the second monitoring with a concentration of ～4 μg/kg_{dry soil}, but it was not detected in the third, indicating that is was not accumulated in the environment. The heptachlor was the compound most commonly found in all water samples, within a range of 0.45–1.25 ng/L. The presence of this organochlorine compound in the water samples indicated a possible migration from the soil to water bodies due to soil erosion. The presence of organophosphorus compounds was not detected in the water samples, which could be attributed to the moderate persistence of these compounds and their consequent degradation before arriving at the water bodies.     

Methyl tert-butyl ether (MTBE) in finished drinking water in Germany

In the present study 83 finished drinking water samples from 50 cities in Germany were analyzed for methyl tert-butyl ether (MTBE) content with a detection limit of 10 ng/L. The detection frequency was 46% and the concentrations ranged between 17 and 712 ng/L. Highest concentrations were found in the community water systems (CWSs) of Leuna and Spergau in Saxony-Anhalt. These CWSs are supplied with water possibly affected by MTBE contaminated groundwater. MTBE was detected at concentrations lower than 100 ng/L in drinking water supplied by CWSs using bank filtered water from Rhine and Main Rivers. The results from Leuna and Spergau show that large groundwater contaminations in the vicinity of CWSs pose the highest risk for MTBE contamination in drinking water. CWSs using bank filtered water from Rhine and Main Rivers are susceptible to low MTBE contaminations in finished drinking water. All measured MTBE concentrations were below proposed limit values for drinking water.     

Tea bag filter paper as a novel protective membrane for micro-solid phase extraction of butachlor in aqueous samples

An innovative, cost-effective, simple, and environmental friendly tea bag filter paper protected micro-solid phase extraction (μ-SPE) technique was developed for the first time with the aim to miniaturize and minimize the use of organic solvents for the extraction and determination of butachlor in aqueous samples. The μ-SPE device was produced by packing 3.0 mg of an easily synthesized new sorbent, hydroxyl-functionalized polypyrrole (OH-PPY), inside a small tea bag filter paper sachet (1.0 cm × 0.5 cm) that served as a protective envelope. Both the extraction and desorption procedures were facilitated by sonication. Due to the high porosity and the fast water absorption of the tea bag filter paper, the analyte could easily diffuse through and enhance the interaction with the sorbent. Under the optimized conditions for the GC-ECD and the μ-SPE, the limit of detection (S/N ≥ 3) was 2.0 μg L^?1 while the limit of quantitation (S/N ≥ 10) was 10.0 μg L^?1. The recoveries of the butachlor spiked at 0.050, 0.10, and 0.50 μg mL^?1 ranged from 77.9 ± 3.0 to 112.5 ± 2.9%. The proposed method was successfully applied for the determination of butachlor in water samples from paddy cultivation sites. The levels found were from non-detectable to 24.71 ± 0.37 μg L^?1.     

Assessment of pesticide contamination in Akkar groundwater,northern Lebanon

According to its high production and value, Akkar is considered as the second agricultural region in Lebanon. Groundwater constitutes the principal source of water in Akkar including drinking water of local inhabitants in Akkar. As such, the contamination of groundwater by organic pollutants can impact directly the population health. In this study, we evaluated the contamination status of groundwater in this region. Three classes of pesticides including 19 organochlorine (OC) pesticides, 8 organophosphorus (OP) pesticides, and 6 organonitrogen (ON) pesticides were monitored in 15 groundwater samples collected from different villages on the Akkar plain. Samples were extracted by using solid phase extraction (SPE) and analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The results showed high contamination of Akkar groundwater by OCs with levels that can reach 58.9 μg/L. They were detected in the majority of the sample and represent 95–100% of ∑pesticides. Our results showed the recent use of these molecules with an average level of 0.3 and 0.39 μg/L for ∑HCHs and DDTs, respectively. Their concentrations were higher than those observed in the same region in 2014 and other regions elsewhere. OPs were also detected at high levels and among them, methylparathion was the predominant OP detected (44.6 μg/L). For ONs, lower levels were measured in all samples with a mean value of 5.6 μg/L. As a conclusion of this work, groundwater on the plain of Akkar was remarkably contaminated by the studied pesticides; indefinitely, more efforts should be taken to manage the pesticide use in this region, assess, and reduce their effects on human health. In the future, the application of organic farming can be a great solution to the groundwater contamination problem.     

Occurrence and behaviour of pharmaceutical compounds in a Portuguese wastewater treatment plant: Removal efficiency through conventional treatment processes

Wastewater treatments can eliminate or remove a substantial amount of pharmaceutical active compounds (PhACs), but there may still be significant concentrations of them in effluents discharged into surface water bodies. Beirolas wastewater treatment plant (WWTP) is located in the Lisbon area and makes its effluent discharges into Tagus estuary (Portugal). The main objective of this study is to quantify a group of 32 PhACs in the different treatments used in this WWTP. Twelve sampling campaigns of wastewater belonging to the different treatments were made in 2013–2014 in order to study their removal efficiency. The wastewaters were analysed by solid phase extraction (SPE) and ultra-performance liquid chromatography coupled with tandem mass detection (UPLC–MS/MS). The anti-diabetics were the most frequently found in wastewater influent (WWI) and wastewater effluent (WWE) (208 and 1.7 μg/L, respectively), followed by analgesics/antipyretics (135 μg/L and < LOQ, respectively), psychostimulants (113 and 0.49 μg/L, respectively), non-steroidal anti-inflammatory drugs (33 and 2.6 μg/L, respectively), antibiotics (5.2 and 1.8 μg/L, respectively), antilipidemics (1.6 and 0.24 μg/L, respectively), anticonvulsants (1.5 and 0.63 μg/L, respectively) and beta blockers (1.3 and 0.51 μg/L, respectively). A snapshot of the ability of each treatment step to remove these target PhACs is provided, and it was found that global efficiency is strongly dependent on the efficiency of secondary treatment. Seasonal occurrence and removal efficiency was also monitored, and they did not show a significant seasonal trend.     

Simultaneous determination of estrogenic odorant alkylphenols,chlorophenols, and their derivatives in water using online headspace solid phase microextraction coupled with gas chromatography-mass spectrometry

A simple online headspace solid-phase microextraction (HS-SPME) coupled with the gas chromatography-mass spectrometry (GC-MS) method was developed for simultaneous determination of trace amounts of nine estrogenic odorant alkylphenols and chlorophenols and their derivatives in water samples. The extraction conditions of HS-SPME were optimized including fiber selection, extraction temperature, extraction time, and salt concentration. Results showed that divinylbenzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was the most appropriate one among the three selected commercial fibers, and the optimal extraction temperature, time, and salt concentration were 70 °C, 30 min, and 0.25 g/mL, respectively. The developed method was validated and showed good linearity (R ²?>?0.989), low limit of detection (LOD, 0.002–0.5 μg/L), and excellent recoveries (76–126 %) with low relative standard deviation (RSD, 0.7–12.9 %). The developed method was finally applied to two surface water samples and some of these target compounds were detected. All these detected compounds were below their odor thresholds, except for 2,4,6-TCAS and 2,4,6-TBAS wherein their concentrations were near their odor thresholds. However, in the two surface water samples, these detected compounds contributed to a certain amount of estrogenicity, which seemed to suggest that more attention should be paid to the issue of estrogenicity rather than to the odor problem.     

Hematological and histopathological changes in silver catfish Rhamdia quelen (Siluriformes) exposed to clomazone herbicide in the Madre River,Santa Catarina State,Southern Brazil

This study evaluated the influence of the clomazone herbicide (2-[(2-chlorophenyl)methyl]-4,4-dimethyl-3-isoxazolidinone) contamination on the hematological parameters and histological changes in gills and liver of silver catfish (Rhamdia quelen) from Madre River, Santa Catarina State, Southern Brazil. Fish were collected between March 2010 and January 2012 at two different sites of the Madre River, one site receiving residual water (contaminated site) from rice culture (n = 49) and another that do not receive residual water (reference site) (n = 48). The herbicide clomazone analysis detected 3.40 ± 1.70 μg/L in the contaminated site and 1.1 ± 0.33 μg/L in the reference site. Fish from contaminated site showed increased (P < 0.05) number of monocytes suggesting the possible defense response as a result of chronic exposure to clomazone. On the other hand, no difference was found in the hematocrit percentage, red blood cell count, total thrombocyte number, white blood cell count, lymphocytes, and neutrophils number. Fish from both sites showed histopathological changes in gills and liver, possibly caused by chronic exposure to contamination. The influence of herbicide sub doses on fish health is also discussed.     

Distribution,sources, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface water in industrial affected areas of the Three Gorges Reservoir,China

Water samples were collected from wastewater treatment plant (WWTP), drain water (DW), major tributaries (MT), and main course of the Yangtze River (MY) in areas of three industrial parks (IPs) in Chongqing city in the Three Gorges Reservoir (TGR). Sixteen EPA priority polycyclic aromatic hydrocarbon (PAH) pollutants were quantified to identify the effects of industrial activities on water quality of the TGR. The results showed that 11 individual PAHs were quantified and 5 PAHs (naphthalene (Nap), acenaphthylene (Acy), benzo[k]fluoranthene (BkF), indeno[1,2,3-cd]pyrene (InP), and benzo[g,h,i]perylene (BgP)) were under detection limits in all of the water samples. Three-ring and four-ring PAHs were the most detected PAHs. Concentrations of individual PAHs were in the range of not detected (nd) to 24.3 ng/L. Total PAH concentrations for each site ranged from nd to 42.9 ng/L and were lower compared to those in other studies. The mean PAH concentrations for sites WWTP, DW, MT, and MY showed as follows: DW (25.9 ng/L) > MY (15.5 ng/L) > MT (14.0 ng/L) > WWTP (9.3 ng/L), and DW contains the highest PAH concentrations. Source identification ratios showed that petroleum and combustion of biomass coal and petroleum were the main sources of PAHs. The results of potential ecosystem risk assessment indicated that, although PAH concentrations in MT and MY are likely harmless to ecosystem, contaminations of PAHs in DW were listed as middle levels and some management strategies and remediation actions, like strengthen clean production processes and banning illegal sewage discharging activities, etc., should be taken to lighten the ecosystem risk caused by PAHs especially risks caused by water discharging drains.