Leaching of antimony from polyethylene terephthalate (PET) bottles into mineral water

The Sb leaching from polyethylene terephthalate (PET) package material into 10 different brands of still (non-carbonated) and sparkling (carbonated) Hungarian mineral water purchased in supermarkets was investigated by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). The Sb concentration measured in PET package materials varied between 210 and 290 mg/kg. Generally, the Sb concentration of still mineral water was lower than that of sparkling in the case of identical storage time. For modelling improper storage conditions, storage time (10-950 days), temperature (22 °C-70 °C), illumination (dark vs. 23 W daylight lamp for 116 h) as well as bottle volume (0.5, 1.0 and 1.5 L) were taken into consideration. Under certain extreme light and temperature storage conditions, the Sb concentration of some samples exceeded the concentration value of 2 ng/mL. The extent of Sb leaching from the PET recipients of different brands of mineral water can differ by even one order of magnitude in experiments conducted under the same conditions. Thus, the adequate selection of the polymer used for the production of the PET bottle for the solar water disinfection (SODIS) procedure seems to ensure low Sb levels in the water samples.     

Relationship of the raw water quality to mutagens detectable by the Ames Salmonella/microsome assay in a drinking-water supply

Mutagenic activity of non-volatile compounds in dichloromethane extracts of a drinking-water supply derived by conventional treatment (flocculation, sedimentation, sand filtration and chlorination) of river water, was related to the concentration of volatile halogenated hydrocarbons. Limited relationship also existed between mutagenic activity and the total organic carbon content of both the raw and treated water. The dry mass of extracts from neither raw nor treated water correlated with these parameters. Mutagenic activity of the treated water increased during spring, possibly as a result of the first showers of the rainy season washing mutagen precursors into the river, rising temperature, and actively growing algae increasing the concentration of mutagen precursors in the river. After increased river flow, mutagenic activity of the treated water decreased and reached a stable summer level. Mutagenic activity was not detected in the raw water, which indicates that mutagens in partially purified wastewater effluents discharged into the river about 40 km upstream, were removed or inactivated in the river environment. Properties of the drinking-water extracts showed that the mutagens formed during treatment of the water supply consisted mainly of neutral organic compounds inducing frameshift mutations without liver activation. Although the specific activity of mutagens in the extracts does not indicate that the treated water constituted a health hazard, the results illustrate that regular surveillance of potential carcinogens in drinking-water derived by conventional treatment of water subject to pollution may be important.     

Detection of potential carcinogens and toxicants in tap and reclaimed water by the golden hamster cell transformation assay

A transformation assay using primary golden hamster embryonic cells was used for detection of potential carcinogens in water. The system also gave an indication of toxicants present in water and proved to be highly sensitive, because no concentration or extraction procedures were required as in the case of the Ames Salmonella/microsome assay.

Direct reclamation of secondary treated wastewater proved to be highly effective when tested by the golden hamster transformation assay. Reclaimed water showed less transforming activity than a high quality tap water derived from conventional treatment of surface water.     

Analysis of the antioxidant butylated hydroxytoluene (BHT) in water by means of solid phase extraction combined with GC/MS

The antioxidant 3,5-di-tert-butyl-4-hydroxy-toluene (BHT) is widely used as an additive to increase the tenability of food and plastics. BHT is degraded to 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO) in mammals, as well as in the natural environment such as in water and soils. BHT-CHO has been studied extensively in terms of their potential toxicities. The present investigation was carried out to quantify BHT and BHT-CHO in river, ground, rain and drinking water obtained from several locations in Germany. Apart from the compounds mentioned above, 1,2-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)ethane (2-BHT), which is a dimer of BHT, was also detected in the extracts of some ground water samples. The applied analytical method is based on solid phase extraction (SPE) to concentrate trace compounds from water samples followed by gas chromatography/mass spectrometry (GC/MS) of the extracts. A total of 51 of the respective water samples were used for extraction purposes and analyte recoveries were all > or = 80%. The determination limit for BHT was 5 ng l(-1) and for BHT-CHO 16 ng l(-1). The standard deviations for the analytical procedure were 6% for BHT and 10% for BHT-CHO. The use of the antioxidant BHT in Germany has resulted in water concentrations of 7-791 ng l(-1) in the rivers Rhine, Elbe, Main, Oder, Nidda and Schwarzbach. The degradation product BHT-CHO was also detected in the river water samples at concentrations between 29 and 223 ng l(-1). The concentrations of BHT measured in German rivers are lower compared to values measured in the USA and Japan 20 years ago. In ground water, levels for BHT varied from non-detectable up to 2156 ng l(-1) and for BHT-CHO from non-detectable up to 674 ng l(-1). Both compounds were also detected in rain water in Frankfurt/Main at a concentration of 1797 ng l(-1) for BHT and 59 ng l(-1) for BHT-CHO.     

The distribution and origin of mutagens in airborne particulates, detected by the salmonella/microsome assay in relation to levels of lead, vanadium and PAH

At three stations in central Copenhagen, Denmark, samples of particulate matter were collected simultaneously with different contributions from automobile exhaust products. Samples were obtained at street level, 22 m above street level and within a hospital zone; 32 samples were analysed for levels of polycyclic aromatic hydrocarbons (PAH) and elements, as well as for mutagenicity towards S. typhimurium TA1538. Two classes of mutagens were quantified: a non-polar extract rich in PAH and, other promutagens, and a polar extract containing direct acting mutagens (not requiring microsomal activation). Covariances between lead and mutagenicity, and the varying distribution of the polar and non-polar mutagens at the stations, indicate that at all stations the mutagenicity of the non-polar extract is dominated by automobile exhaust products. The polar extract is relatively less influenced by primary traffic emissions; a considerable part of the activity of this extract is attributed to secondary emissions, transformed by atmospheric reactions, and primary emissions from stationary sources.     

Three-step measurement by the Sapromat to evaluate the BOD5, the mineral imbalance and the toxicity of water samples

BOD₅-data obtained by analyzing wastewater samples, both by means of the dilution method and by means of the Sapromat technique, correlated satisfactorily (r = 0·98). However, the Sapromat technique turned out to be susceptible to certain disturbances as e.g. variability of initial microbial inoculum, lack of essential mineral nutrients and presence of toxic compounds. Therefore, a simple three-step Sapromat method is proposed. This method enables one to measure the BOD₅ and to calculate the biodegradation rate. In addition, it also allows to evaluate the possible mineral imbalance, the toxicity and/or the susceptibility to co-oxidation of the wastewater sample.     

Investigation of the microbial degradation of phenazone-type drugs and their metabolites by natural biofilms derived from river water using liquid chromatography/tandem mass spectrometry (LC-MS/MS)

The degradation of the pharmaceuticals phenazone and metamizole, two pyrazolone-derivates in widespread use, using biofilms created by natural organisms from the national park Unteres Odertal, Germany, were investigated. An analytical method based on LC-MS/MS was optimised to determine the substances phenazone and methylaminoantipyrine (MAA), the hydrolysis product of metamizole (also known as dipyrone), as well as their metabolites 1,5-dimethyl-1,2-dehydro-3-pyrazolone (DP), acetaminoantipyrine (AAA), formylaminoantipyrine (FAA) and 4-aminoantipyrine (AA). Performance characteristics of the method were evaluated in terms of recovery, standard deviation, coefficient of variation, method detection limits (MDL) and method quantification limits (MQL). Degradation studies of phenazone and MAA were conducted using a laboratory-scale continuous flow biofilm reactor fed with different nutrient media and with variable hydraulic retention times of 24 and 32 h. MAA was degraded rapidly to FAA and AA, while phenazone was not degraded under the prevailing conditions even after 32 h. By operating the bioreactor in batch mode to study the phenazone degradation potential of the biofilm under limiting nutrient conditions, an elimination rate of 85% phenazone was observed, but because of the slow elimination rate and aerobic conditions, the metabolite DP was not detected. In additional batch experiments using bacterial isolates from the natural biofilm to decompose phenazone, some bacterial strains were able to form DP from phenazone in marginal concentrations over the sampling period of eight weeks. Obviously, the microorganisms need a reasonably long time to adapt their metabolisms to enable the removal of phenazone from water samples.     

Use of semi-permeable membrane devices and solid-phase extraction for the wide-range screening of microcontaminants in surface water by GC-AED/MS

An automated GC-MS-based screening method was developed for over 400 industrial, agrochemical and household chemicals. Extracted ion chromatograms were used and the method was aimed at creating a minimum number of false positives. The compound polarity range usually associated with solid-phase extraction was extended to include very apolar, bioaccumulative, compounds by using the complementary semi-permeable membrane device technique. Real-life samples were taken at four locations in the main Dutch river systems and one in an agricultural area. Some 150 compounds were detected in the low-ng/l to low-microg/l range. Next to the target compounds, several brominated and chlorinated non-target compounds were detected by means of GC with atomic emission detection and tentatively identified using mass spectral library searching.     

Evaluation and validation of a novel Arxula adeninivorans estrogen screen (nAES) assay and its application in analysis of wastewater, seawater, brackish water and urine

A novel Arxula adeninivorans yeast estrogen screen (nAES) assay has been developed for detection of estrogenic activity in various liquid samples such as wastewater, seawater, brackish water and swine urine. Two bio-components were engineered to co-express the human estrogen receptor α (hERα) and an inducible reporter gene; either the non-conventional phytase gene (phyK, derived from Klebsiella sp. ASR1) or the non-conventional tannase gene (ATAN1, derived from Arxula). Both reporters were put under the control of an Arxula derived glucoamylase (GAA) promoter, which was modified by the insertion of two estrogen-responsive elements (EREs). The Arxula transformation/expression platform Xplor® 2, which lacks resistance markers and E. coli elements, was used to select stable mitotic transformants. They were then analyzed for robustness and suitability as the bio-component for the nAES assay. Two types of the nAES assay based on the reporter proteins phytase and tannase (nAES-P, nAES-T) were used in this work. The nAES-P type is more suitable for the analysis of seawater, brackish water and urine whereas the nAES-T type exhibited higher robustness to NaCl. Both assay types have similar characteristics for the determination of estrogen in sewage and urine samples e.g. 6-25 h assay period with detection and determination limits and EC₅₀ values for 17β-estradiol of 2.8 ng L^− 1, 5.9 ng L^− 1, 33.2 ng L^− 1 (nAES-P) and 3.1 ng L^− 1, 6.7 ng L^− 1 and 39.4 ng L^− 1 (nAES-T). Substrate specificity and analytical measurement range (AMR) for both assay types are also similar. These characteristics show that the nAES assay based on non-conventional salt tolerant yeast is applicable for a high throughput estrogen analysis in the environmental and regulatory control sectors.     

承压水沿煤层底板递进导升突水机理的模拟与观测

完整底板和非完整底板的注水试验表明,底板深处的耗水早于浅部,显示底板的破裂发生在采前。相似材料模拟具一定导升高度的底板在采动中的变化揭示了同样的规律,底板的原位测试发现承压水在采前出现了向上入侵的现象, 二次应力给导升的发展提供条件,递进导升是突水的一种机理。     

超快速液相色谱-串联质谱法检测人血清中雌酮、雌二醇及雌三醇的方法学研究

建立灵敏、可靠、稳定的柱前衍生化超快速液相色谱-串联质谱(ultra-fast liquid chromatography-mass spectrometry,UFLC-MS/MS)方法检测人血清中超微量雌酮、雌二醇和雌三醇。方法:取200μL血清样品,采用两步液萃取法,通过丹磺酰氯衍生化后进行样品分析,以雌二醇-d3作为内标。采用Welch Ultimate UHPLC XB-C18色谱柱(2.1mm×50mm,1.8μm),乙腈-水(含0.1%甲酸)为流动相,梯度洗脱,流速0.20mL/min,柱温40℃,进样量10μL。在电喷雾离子(electrospray ionization,ESI)源正离子模式下,选择多反应监测(multiple reaction monitoring,MRM)模式。经检测,雌酮、雌二醇、雌三醇及内标的检测离子对分别为:m/z为504.0→171.0、m/z为506.0→171.0、m/z为522.0→171.0和m/z为509.0→171.0。结果:丹磺酰氯衍生法可大幅度提高雌酮、雌二醇、雌三醇在ESI源下的离子化效率,血清中3种成分的线性范围均为0.01~5.00μg/L,定量下限均达到10ng/L,样品回收率50%以上,批内、批间准确度与精密度均小于15%,满足生物样品的分析要求。结论:该方法灵敏度高、重现性好,可以用于临床血清样品中雌激素水平的定量分析。     

Effect of fats, mineral oils and creosote on the extraction—atomic absorption determination of copper, iron, lead and manganese in water

The effect of five mineral oils, two fats and creosote on the extraction—atomic absorption spectrophotometric determination of copper, iron, lead and manganese in water was investigated. Pure mineral oils, fats and creosote gave 100±15% recovery, but soluble oil gave low results for copper and iron. At a soluble oil concentration of 12.5 mg 1⁻¹, the recoveries of copper and iron were, respectively 41 and 72%.     

Evaluation of the EUROSEM model for predicting the effects of erosion-control blankets on runoff and interrill soil erosion by water

The European Soil Erosion Model (EUROSEM, Morgan et al., 1998) is an event-based soil erosion model which predicts runoff and sediment discharge for different environmental conditions. Applying geotextiles or erosion-control blankets (ECB’s) on the soil surface significantly affects surface seal formation and topsoil properties and therefore controls runoff and soil erosion rates during a rainfall event. Since these within-storm changes of soil surface characteristics and hydrological conditions are not incorporated in EUROSEM, errors in runoff and soil erosion predictions may occur for soil surfaces covered with ECB’s.Therefore, the objective of this paper is to evaluate and improve the performance of a research version of the physically-based erosion model EUROSEM (EUROSEM-2010; Borselli and Torri, 2010) for simulating the effects of ECB’s on runoff and interrill soil erosion by water during intense simulated rainfall events. Results of model simulations are compared with experimental results of interrill erosion using biological (i.e. natural) ECB’s and simulated rainfall. Because ECB’s applied on the soil surface retard seal formation, the differences between observed and predicted runoff rates and sediment discharges are rather high during the first 20-30 min of the simulated rainstorm. Therefore, a simple approach is proposed to cope with the dynamic evolution of some soil characteristics, i.e. saturated hydraulic conductivity, soil erodibility and soil cohesion, during an intense rainfall event. This time-dependent approach improves the predictions of runoff rate and sediment discharge during the first 20-30 min of a rainfall event and increases the model efficiency (i.e. a measure for the goodness of fit) from 0.84 to 0.98 and from 0.48 to 0.68 for the total runoff volume and soil loss, respectively. For most conditions, the predicted final sediment discharge is still considerably larger than the observed values, which can be partly attributed to the deposition of sediment in the bare soil patches (i.e. inter-weave open areas) of the ECB’s, which is not simulated by EUROSEM in this study. This model approach increases our understanding of the effects of ECB’s on within-storm changes in hydrological conditions and soil surface characteristics.     

Regeneration of N, P and Si near the sediment/water interface of lakes from Southwestern China Plateau

Lake water, pore water, and sediments were sampled in both polluted and unpolluted lakes from Southwestern (SW) China Plateau. The results show that although the mechanisms of nutrient regeneration were similar in the polluted and unpolluted lakes, the processes, however, were much stronger in the polluted lakes. Nitrogen regeneration was mainly of organic process. Phosphorus regeneration was essentially controlled by iron redox cycling near sediment/water interface. Nutrient upward fluxes were in the order SiO2 > NH4+ > PO4(3-). This study has significance for further investigating the response of nutrient biogeochemistry to the increasing nutrient levels in aquatic environments.     

Removal of saxitoxins from drinking water by granular activated carbon, ozone and hydrogen peroxide--implications for compliance with the Australian drinking water guidelines

In a laboratory-scale trial, we studied the removal of saxitoxins from water by ozone, granular activated carbon (GAC) and H₂O₂, and considered the implications of residual toxicity for compliance with the Australian drinking water standards. Cell-free extracts of Anabaena circinalis were added to raw, untreated drinking water obtained from a water supply reservoir to provide a toxicity of 30 μg (STX equivalents) l⁻¹. Ozone alone, or in combination with H₂O₂, failed to destroy the highly toxic STX and GTX-2/3, and only partially destroyed dc-STX, and the low-toxicity C-toxins and GTX-5. In all cases, the toxicity of the water was reduced by less than 10%. GAC removed all of the STX, dc-STX and GTXs, but only partially removed the C-toxins. However, the residual toxicity was reduced to the suggested Australian drinking water guideline concentration of 3 μg (STX equivalents) l⁻¹ without O₃ pre-treatment. Modelling the spontaneous chemical degradation of residual C-toxins following treatment shows that residual toxicity could increase to 10 μg l⁻¹ after 11 d due to formation of dc-GTXs and would then gradually decay. In all, residual toxicity would exceed the Australian drinking water guideline concentration for a total of 50 d.     

Evaluation of the lactose Tergitol-7, m-Endo LES, Colilert 18, Readycult Coliforms 100, Water-Check-100, 3M Petrifilm EC and DryCult Coliform test methods for detection of total coliforms and Escherichia coli in water samples

In this study we compared the reference membrane filtration (MF) lactose Tergitol-7 (LTTC) method ISO 9308-1:2000 with the MF m-Endo LES method SFS 3016:2001, the defined substrate chromogenic/fluorogenic Colilert 18, Readycult Coliforms and Water Check methods, and ready-made culture media, 3M Petrifilm EC and DryCult Coli methods for the detection of coliforms and Escherichia coli in various water samples. When the results of E. coli detection were compared between test methods, the highest agreement (both tests negative or positive) with the LTTC method was calculated for the m-Endo LES method (83.6%), followed by Colilert 18 (82.7%), Water-Check (81.8%) and Readycult (78.4%), whereas Petrifilm EC (70.6%) and DryCult Coli (68.9%) showed the weakest agreement. The m-Endo LES method was the only method showing no statistical difference in E. coli counts compared with the LTTC method, whereas the Colilert 18 and Readycult methods gave significantly higher counts for E. coli than the LTTC method. In general, those tests based on the analysis of a 1-ml sample (Petrifilm EC and DryCult Coli) showed weak sensitivity (39.5-52.5%) but high specificity (90.9-78.8%).     

Evaluation of effect of leaching medium on the release of copper,chromium, and arsenic from treated wood

There is increasing public concern about environmental contamination from preservative treated wood due to release of toxic preservative components to the environment. Leaching of wood preservatives from treated wood in service can be affected by a number of factors such as wood and preservative treatment characteristics and properties of water and soil substrate in which treated wood is placed i.e. salinity, pH, and temperature. Laboratory leaching tests usually require distilled or deionized water for leaching procedure however treated wood is generally exposed to different types of water and soil conditions. This study evaluates the release of copper, chromium and arsenic elements from chromated copper arsenate (CCA)-treated wood exposed to either distilled water, tap water, sea water or humic acid. Leaching tests were conducted in laboratory conditions using wood blocks treated with CCA wood preservative at either low or high retention levels. Results showed that tap water resulted in less preservative release when compared to the other leaching media used in the study. Humic acid was the most effective medium causing more element leaching. The percentage of components leached was always higher in wood blocks treated at the high retention in comparison with the low retention level. Our results from the leaching tests can be important in developing more realistic standard leaching methods to evaluate preservative components to be released from treated wood.     

The uptake from fresh water and subsequent clearance of a vanadium burden by the common eel (Anguilla anguilla)

The uptake of ⁴⁸V vanadium from a solution of 10^?5M⁴⁸V-orthovanadate by freshwater elvers and the subsequent depletion of the vanadium burden was studied. At the end of the 8-week loading period, the levels of ⁴⁸V were still increasing in the liver, kidney, bone and carcase. The uptake rate for the whole fish over the 8-week period was 760 pg atom/h/100 g body wt and the depletion rate over the following 5 weeks in clean water was about one tenth of this. Liver contained the highest amount of ⁴⁸V at the end of the 8-week loading period, calculated as equivalent to 1.1 × 10⁴ g atom V/kg wet wt, and this level was unchanged at the end of the 5-week depletion period. Less than 1% of the carcase ⁴⁸V was present in the fraction of MW under 2000.     

Evaluation of the acute, chronic and teratogenic effects of a mixture of eleven pharmaceuticals on the cnidarian, Hydra attenuata

Pharmaceuticals have recently emerged as novel pollutants of potential concern in the aquatic environment where they are commonly introduced as complex mixtures via municipal effluent. In the present experiment, the freshwater cnidarian Hydra attenuata was exposed to a mixture of 11 pharmaceuticals (ibuprofen, naproxen, gemfibrozil, bezafibrate, carbamazepine, sulfapyridine, oxytetracycline, novobiocin, trimethoprim, sulfamethoxazole and caffeine) up to 10 000 times (×) the concentration found in municipal effluent. Hydra regeneration and teratogenicity was measured, having an IC₅₀ of 781× and was found to be non teratogenic with an A/D value of ∼ 1. Toxicity was investigated using both lethal (based on morphology) and sub-lethal (based on morphology, feeding behaviour, hydranth number and attachment) endpoints. The pharmaceutical mixture incurred a significant decrease in morphology at 0.1, 10 and 100× but a significant increase at 1000×. All parameters were significantly reduced at 10 000×. An EC₅₀ of 425× and 65× based on morphology and feeding respectively and a toxicity threshold (TT) of 3.2× were calculated. When compared to the toxicity of each pharmaceutical exposed individually as previously reported [Quinn B, Gagné F, Blaise C. An investigation into the acute and chronic toxicity of eleven pharmaceuticals found in wastewater effluent on the cnidarian, H. attenuata. Sci Total Environ 2008a; 389: 306-314], the compounds in the mixture were present at concentrations 2 to 3 orders of magnitude lower for the equivalent toxicity (EC₅₀ and TT). These results indicate that pharmaceuticals act additively in a mixture, having sub-lethal effects at environmentally relevant (µg/L-ng/L) concentrations and that their combined concentrations could potentially prove significantly ecotoxic to Hydra and possibly to other aquatic taxa.