Journal Of Environmental Monitoring[JOURNAL]
Sun
200 papers
Occurrence and removal of endocrine-disrupting chemicals in wastewater treatment plants in the Three Gorges Reservoir area, Chongqing, China.
Ye X, Guo X, Cui X … +5 more , Zhang X, Zhang H, Wang MK, Qiu L, Chen S
J Environ Monit · 2012 Aug · PMID 22695474 · Publisher ↗
Concentrations of six endocrine-disrupting compounds (EDCs), bisphenol A (BPA), estrone (E(1)), 17β-estradiol (E(2)), estriol (E(3)), 17α-ethynylestradiol (EE(2)) and diethylstilbestrol (DES), were assessed in influents,...
Concentrations of six endocrine-disrupting compounds (EDCs), bisphenol A (BPA), estrone (E(1)), 17β-estradiol (E(2)), estriol (E(3)), 17α-ethynylestradiol (EE(2)) and diethylstilbestrol (DES), were assessed in influents, effluents and excess sludge in ten municipal wastewater treatment plants (WWTPs) in the Three Gorges Reservoir (TGR) area, Chongqing, China. Three types of activated sludge treatment processes, oxidation ditch (OD), reversed anaerobic-anoxic-oxic (rA(2)/O) technology and sequential batch reactor (SBR), were used in the surveyed WWTPs. These WWTPs were all combined landfill leachate-sewage treatment plants. All analytes were extracted by solid-phase extraction (SPE) in the dissolved phase and by accelerated solvent-based extraction (ASE) in sludge. Gas chromatography-mass spectrometry (GC-MS) was employed for the analysis of EDCs. Among these EDCs, BPA was the most frequently detected and abundant compound (100.0-10566.7 ng L(-1), 15.5-1210.7 ng L(-1) and 85.0-2470.4 ng g(-1) with respect to the influents, effluents and excess sludge samples). The greatest levels of steroidal estrogens in municipal influents were observed in E(3) which were all >100 ng L(-1), followed by E(1) (42.2-110.7 ng L(-1)) and E(2) (7.4-32.7 ng L(-1)), and in the effluents and sludge were E(1) > E(3) > E(2) which were all <31 ng L(-1) and 105 ng g(-1), respectively. Regarding synthetic estrogens, EE(2) was frequently detected in the influents, occurring below 50 ng L(-1), while DES was not detected at all. A high correlation coefficient was observed between the leachate-sludge ratio and concentrations of influent EDCs, and it was statistically significant (i.e., R > 0.65, P < 0.05), but removal efficiency of the EDCs did not show significant differences with OD, rA(2)/O and SBR processes. Furthermore, modification of treatment technology as well as operational parameters, such as hydraulic retention time (HRT), sludge retention time (SRT) and disinfection process (DP), were recommended to further eliminate the residual EDCs.
Hygienic guidance values for wipe sampling of antineoplastic drugs in Swedish hospitals.
Hedmer M, Wohlfart G
J Environ Monit · 2012 Jul · PMID 22692549 · Publisher ↗
The use of antineoplastic drugs in health care steadily increases. Health care workers can be occupationally exposed to antineoplastic drugs classified as carcinogenic or teratogenic. Monitoring of surface contamination...
The use of antineoplastic drugs in health care steadily increases. Health care workers can be occupationally exposed to antineoplastic drugs classified as carcinogenic or teratogenic. Monitoring of surface contamination is a common way to assess occupational exposure to antineoplastic drugs, since wipe sampling is used as a surrogate measure of dermal exposure. Since no occupational limits for antineoplastic drugs in work environments exist, 'hygienic guidance values' (HGVs) should be used instead. HGVs are practicable, achievable levels, not health based, and can be calculated from exposure data from representative workplaces with good occupational hygiene practices. So far, guidance values for surface monitoring of antineoplastic drugs only exist for pharmacies where antineoplastic drugs are prepared. The objective was to propose HGVs for surface monitoring of cyclophosphamide (CP) and ifosfamide (IF) in Swedish hospitals where antineoplastic drugs are administered to patients. In total, 17 workplaces located at six hospitals in Sweden were surveyed by wipe sampling. Wipe samples were collected, worked up and then analyzed with liquid chromatography tandem mass spectrometry. Surface contamination of CP and IF was found on 80% and 73% of the sampled surfaces, thus indicating that there is potential for health care workers to be exposed to CP and IF via the skin. The median surface load of CP was 3.3 pg cm(-2) (range <0.05-10,800 pg cm(-2)). The corresponding value for IF was 4.2 pg cm(-2) (range <0.13-95,000 pg cm(-2)). The highest surface loads were found on the floors. The proposed HGVs were set at 90th percentile values, and can be applicable to hospital workplaces where patients are treated with CP or IF. Surface monitoring combined with HGVs is a useful tool for health care workers to regularly benchmark their own surface loads which could control and reduce the occupational exposure to CP and IF in hospital workplaces. Thus, the occupational safety of the health care workers will be increased.
Study on transfers of uranium, thorium and decay products from grain, water and soil to chicken meat and egg contents.
Jeambrun M, Pourcelot L, Mercat C … +4 more , Boulet B, Loyen J, Cagnat X, Gauthier-Lafaye F
J Environ Monit · 2012 Aug · PMID 22689007 · Publisher ↗
Activity concentrations of the uranium and thorium series radionuclides were determined in chicken meat and eggs as well as in soil, water and other dietary intakes of poultry at five sites of the French territory. These...
Activity concentrations of the uranium and thorium series radionuclides were determined in chicken meat and eggs as well as in soil, water and other dietary intakes of poultry at five sites of the French territory. These data allow the calculation of transfer coefficients which enrich the database given by the technical report series no. 472 of the IAEA. In egg contents, the highest activity concentrations (in mBq kg(-1) fresh weight) are for (226)Ra, ranging between 136 and 190 and are much lower for uranium (between 0.51 and 1.30 for (238)U). In chicken meat, (238)U activity concentration is higher than in egg contents and ranges between 1.7 and 9.7. Concerning (232)Th, its activity concentration is lower than uranium and ranges between 0.5 and 4.9. Daily ingested activity concentration by the animals was assessed taking into account the activity concentrations measured in the grains, in the soil and in the drinking water. The activity concentration in grains and the daily intakes allow the calculation of concentration ratios and transfer coefficients for chicken meat and egg contents. In chicken meat the transfer coefficients (d kg(-1)) range between 0.0018 and 0.0073 for (238)U and between 0.0008 and 0.0028 for (232)Th. In egg contents they range from 0.00018 to 0.0018 for (238)U and are much higher for radium isotopes (0.10-0.23 for (226)Ra and 0.07-0.11 for (228)Ra).
Regulation of the dissolved phosphate concentration of a mountainous stream, Kitakyushu, southwestern Japan.
Koga M, Yoshimura K
J Environ Monit · 2012 Jul · PMID 22673628 · Publisher ↗
The phosphate concentration in mountainous stream water can be a measure of the forest condition, because its concentration will be low when the biomass in the forest is increasing and vice versa when the forest is decli...
The phosphate concentration in mountainous stream water can be a measure of the forest condition, because its concentration will be low when the biomass in the forest is increasing and vice versa when the forest is declining. To investigate the seasonal change in the dissolved phosphate concentration of the mountainous stream water of the Yamakami River, Kitakyushu, from June 2009 to August 2010, and the regulation mechanism of the phosphate concentration, solid-phase spectrophotometry, which can be applicable to natural water without any pretreatment procedures, was employed for the determination of phosphate at μg P L(-1) levels in natural water. The phosphate concentrations in the mountainous stream waters at 6 sites ranged from 2.2 to 13 μg P L(-1), and those from the catchment area of the steady state forest were 5.3 ± 1.6 (±1 SD) μg P L(-1). Changes in the concentration were fairly small even during a storm runoff. The average phosphate concentration of rain was 2.8 ± 0.7 μg P L(-1), about half of the concentration in the stream water. The rate of runoff in forest areas is generally considered to be about 50% of the total precipitation. For a forest under a climax condition, the phosphate concentration is estimated to be regulated by the fallout and evapotranspiration (α = 0.05). At one of the sites, an upstream tributary, where a fairly big landslide occurred before July in 2009, the phosphate concentration was the highest, suggesting that the biomass may still be decreasing. For all of the six sites examined, a characteristic seasonal change in phosphate concentration was observed, reflecting the local budget between the biological decomposition of plant matter and the consumption by the biomass. The increase in the phosphate concentration during late spring and early summer may result from the extensive decomposition of plant litter mainly supplied in autumn and of plant matter relating to spring blooming such as fallen flowers, pollen and immature fruits. The proposed method using the phosphate concentration in surface stream waters without the period of the seasonal change mentioned above is expected to be very helpful in diagnosing the condition of forests.
Spatial, temporal, and speciation variations of heavy metals in sediments of Nan'ao Island, a representative mariculture base in Guangdong coast, China.
Gu Y, Yang Y, Lin Q … +3 more , Li Q, Wang Z, Wang X
J Environ Monit · 2012 Jul · PMID 22673585 · Publisher ↗
Heavy metals in sediments from Baisha Bay, Nan'ao Island, one of Guangdong Province's largest mariculture bases in Southern China, were investigated. The results display that the concentrations of 6 heavy metals from sur...
Heavy metals in sediments from Baisha Bay, Nan'ao Island, one of Guangdong Province's largest mariculture bases in Southern China, were investigated. The results display that the concentrations of 6 heavy metals from surface sediments were 0.040-0.220 (Cd), 24.22-39.61 (Pb), 25.30-42.66 (Cr), 10.83-19.54 (Ni), 15.06-39.24 (Cu) and 55.12-141.73 mg kg(-1) (Zn), respectively. The highest concentrations and the greatest increasing rates of heavy metals were found in a sediment core in a fish cage culture area due to receiving sewage discharge, uneaten fish bait, and boat gasoline combustion. Cd was preferentially associated with the acid-soluble fraction and Pb mainly with the reducible fraction in surface sediments. Meanwhile, Cd and Pb displayed greatest labile fractions, indicating anthropogenic origin. A principal component analysis (PCA) revealed three groupings (Cd; Cr, Ni and Cu; Pb and Zn) that mainly result from different distributions of the metals in the various fractions. The ecological risk of the polluted sediments stemmed mainly from Cd, and from Pb and Cu to a lesser degree. It is suggested that the density of fish-stocking be controlled, periodic movement of rafts (cages) be introduced, and the total numbers of net-cages and human activities in the mariculture zones be restricted. in order to facilitate the recovery of the polluted sediment.
Removal of organic toxic chemicals using the spent mushroom compost of Ganoderma lucidum.
Liao CS, Yuan SY, Hung BH … +1 more , Chang BV
J Environ Monit · 2012 Jul · PMID 22673540 · Publisher ↗
The removal of the organic toxic chemicals di-n-butyl phthalate (DBP), di-2-ethyl hexyl phthalate (DEHP), nonylphenol (NP), and bisphenol-A (BPA) by laccase obtained from the spent mushroom compost (SMC) of the white rot...
The removal of the organic toxic chemicals di-n-butyl phthalate (DBP), di-2-ethyl hexyl phthalate (DEHP), nonylphenol (NP), and bisphenol-A (BPA) by laccase obtained from the spent mushroom compost (SMC) of the white rot fungi, Ganoderma lucidum, was investigated. The optimal conditions for the extraction of laccase from SMC required using sodium acetate buffer (pH 5.0, solid : solution ratio 1 : 5), and extraction over 3 h at 4 °C. The removal of NP was enhanced by adding CuSO(4) (1 mM), MnSO(4) (0.5 mM), tartaric acid (20 mM), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS; 1 mM), and 1-hydroxybenzotriazole (HBT; 20 mg L(-1)), with ABTS yielding a higher NP removal efficiency than the other additives. At a concentration of 2 mg L(-1), DBP, DEHP, NP, and BPA were almost entirely removed by laccase after incubation for 1 day. The removal efficiencies, in descending order of magnitude, were DBP > BPA > NP > DEHP. We believe that these findings could provide useful information for improving the efficiency of the removal of organic toxic chemicals in the environment.
Investigations of mercury concentrations in walleye and other fish in the Athabasca River ecosystem with increasing oil sands developments.
Evans MS, Talbot A
J Environ Monit · 2012 Jul · PMID 22652822 · Publisher ↗
Recent studies have reported an increasing trend of mercury concentrations in walleye (Sander vitreus) from the Athabasca River, north eastern Alberta (Canada); these studies were based on three years of comparison and a...
Recent studies have reported an increasing trend of mercury concentrations in walleye (Sander vitreus) from the Athabasca River, north eastern Alberta (Canada); these studies were based on three years of comparison and attributed the mercury increase to expanding oil sands developments in the region. In order to conduct a more comprehensive analysis of mercury trends in fish, we compiled an extensive database for walleye, lake whitefish (Coregonus clupeaformis), northern pike (Esox lucius) and lake trout (Salvelinus namaycush) using all available data obtained from provincial, federal, and industry-funded monitoring and other programs. Evidence for increasing trends in mercury concentrations were examined for each species by location and year also considering fish weight and length. In the immediate oil sands area of the Athabasca River, mercury concentrations decreased (p < 0.001) in walleye and lake whitefish over 1984-2011. In western Lake Athabasca and its delta, mercury concentrations decreased (p < 0.0001) in northern pike (1981-2009) although no trend was evident for walleye (1981-2005) and lake trout (1978-2009). Mercury concentrations in lake trout from Namur Lake, a small lake west of the oil sands area, were higher in 2007 than 2000 (p < 0.0001); it is difficult to ascribe this increase to an oil sands impact because similar increases in mercury concentrations have been observed in lake trout from similar sized lakes in the Northwest Territories. While mercury emissions rates have increased with oil sands development and the landscape become more disturbed, mercury concentrations remained low in water and sediments in the Athabasca River and its tributaries and similar to concentrations observed outside the development areas and in earlier decades. Our fish database was assembled from a series of studies that differed in study purpose, design, and analytical methods. Future monitoring programs investigating mercury trends in fish should be more rigorous in their design.
Apportioning variability of polycyclic aromatic hydrocarbons (PAHs) and chlordanes in indoor and outdoor environments.
Zhu X, Jia C
J Environ Monit · 2012 Jul · PMID 22652751 · Publisher ↗
Measurements of semi-volatile organic compounds (SVOCs) in air are subject to substantial variability and uncertainty. This study apportions total variance of polycyclic aromatic hydrocarbons (PAHs) and chlordanes to var...
Measurements of semi-volatile organic compounds (SVOCs) in air are subject to substantial variability and uncertainty. This study apportions total variance of polycyclic aromatic hydrocarbons (PAHs) and chlordanes to variability and uncertainty components. Concentrations of PAHs and chlordanes were measured inside and outside of 116 residences in three large cities in the U.S. during 1999-2000. Total variance was apportioned to between-city, between-tract, between-residence, and seasonal variation, as well as measurement uncertainty using variance component analysis and log-transformed data for frequently detected compounds. Outdoors, seasonal variation was the greatest portion (44-67%) of total variance, and city effects were significant (19-24%). Indoors, seasonality dominated variability of PAH measurements (>50%). Gas-phase PAHs varied more within city than between cities; particulate-phase PAHs varied significantly between cities but were largely homogeneous within cities. Gas-phase chlordanes showed larger intra-urban variation (63%) than seasonal variation (18%). Measurement uncertainty was generally below 10% with a few exceptions occurring at very low concentrations. Results indicate a need to collect multiple-season samples to account for the large temporal variation between seasons. Samples from centrally located monitoring stations could be representative of ambient SVOCs. Variance component analysis is useful to weigh influential factors in SVOC concentrations, identify and apportion sources, evaluate method performance, and design effective monitoring programs.
Indoor air in schools and lung function of Austrian school children.
Wallner P, Kundi M, Moshammer H … +7 more , Piegler K, Hohenblum P, Scharf S, Fröhlich M, Damberger B, Tappler P, Hutter HP
J Environ Monit · 2012 Jul · PMID 22652689 · Publisher ↗
The Children's Environment and Health Action Plan for Europe (CEHAPE) of WHO focuses (inter alia) on improving indoor environments where children spend most of their time. At present, only little is known about air pollu...
The Children's Environment and Health Action Plan for Europe (CEHAPE) of WHO focuses (inter alia) on improving indoor environments where children spend most of their time. At present, only little is known about air pollution in schools and its effect on the lung function of school children. Our project was set up as an Austrian contribution to CEHAPE. In a cross-sectional approach, differences in indoor pollution in nine elementary all-day schools were assessed and 34 of these pollutants were analyzed for a relationship with respiratory health determined by spirometry using a linear regression model. Overall 596 children (aged 6-10 years) were eligible for the study. Spirometry was performed in 433 children. Socio-economic status, area of living (urban/rural), and smoking at home were included in the model as potential confounders with school-related average concentration of air pollutants as the variable of primary interest. A negative association with flow volumes (MEF(75)) was found for formaldehyde in air samples, benzylbutylphthalate and the sum of polybrominated diphenylethers in school dust. FVC and FEV(1) were negatively associated with ethylbenzene and xylenes in air samples and tris(1,3-dichlor-2-propyl)-phosphate on particulates. Although, in general, the quality of school indoor air was not worse than that reported for homes, effects on the respiratory health of children cannot be excluded. A multi-faceted strategy to improve the school environment is needed.
Chlorinated and brominated dibenzo-p-dioxins and dibenzofurans in surface sediment from Taihu Lake, China.
Zhou L, Li H, Yu Z … +5 more , Ren M, Zeng X, Peng P, Sheng G, Fu J
J Environ Monit · 2012 Jul · PMID 22641387 · Publisher ↗
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in surface sediment samples from Taihu Lake--an important water supply of the Yangtze River D...
Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in surface sediment samples from Taihu Lake--an important water supply of the Yangtze River Delta, China--were investigated in the present study. Concentrations of PCDD/Fs ranged from 0.91 to 4.8 pg TEQ g(-1) dw (mean: 2.9 pg TEQ g(-1) dw, TEQ: Toxic Equivalent), which were all higher than the threshold effect level established by interim sediment quality guidelines in Canada (0.85 pg TEQ g(-1) dw). The levels of PBDD/Fs ranged from 0.16 to 1.6 pg TEQ g(-1) dw (mean: 0.52 pg TEQ g(-1) dw) and accounted for 5-33% (mean: 14%) of the total PCDD/Fs and PBDD/Fs TEQ. Comparatively, the abundance of sedimentary PCDD/Fs in the three regions (Meiliang Bay, Gonghu Bay, and Xukou Bay) showed a decreasing trend from the inflow region to the outflow region, while no significant difference was observed among their 2,3,7,8-PBDD/Fs levels, which suggested that the sources of PCDD/Fs and PBDD/Fs differed in this area. Principal component analysis suggested that the historical production/usage of pentachlorophenol and sodium pentachlorophenate was the dominant source of PCDD/Fs in the sediment of these regions. Although the specific sources of PBDD/Fs in the sediment of Taihu Lake were unclear, it was suspected to be due to atmospheric deposition; however, an additional study is needed to confirm this.
Iodide-assisted total lead measurement and determination of different lead fractions in drinking water samples.
Zhang Y, Ng DQ, Lin YP
J Environ Monit · 2012 Jul · PMID 22622848 · Publisher ↗
Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead c...
Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead contamination and human exposure due to drinking water consumption. The USEPA method for total lead measurement (no. 200.8) is often used to analyze lead levels in drinking water. However, in the presence of high concentration of the tetravalent lead corrosion product PbO(2), the USEPA method was not able to fully recover particulate lead due to incomplete dissolution of PbO(2) particles during strong acid digestion. In this study, a new procedure that integrates membrane separation, iodometric PbO(2) measurement, strong acid digestion and ICP-MS measurement was proposed and evaluated for accurate total lead measurement and quantification of different lead fractions including soluble Pb(2+), particulate Pb(II) carbonate and PbO(2) in drinking water samples. The proposed procedure was evaluated using drinking water reconstituted with spiked Pb(2+), spiked particulate Pb(II) carbonate and in situ formed or spiked PbO(2). Recovery tests showed that the proposed procedure and the USEPA method can achieve 93-112% and 86-103% recoveries respectively for samples containing low PbO(2) concentrations (0.018-0.076 mg Pb per L). For samples containing higher concentrations of PbO(2) (0.089-1.316 mg Pb per L), the USEPA method failed to meet the recovery requirement for total lead (85-115%) while the proposed method can achieve satisfactory recoveries (91-111%) and differentiate the soluble Pb(2+), particulate Pb(II) carbonate and PbO(2).
Insights into ozone deposition patterns from decade-long ozone flux measurements over a mixed temperate forest.
Neirynck J, Gielen B, Janssens IA … +1 more , Ceulemans R
J Environ Monit · 2012 May · PMID 22622798 · Publisher ↗
Long-term fluxes of ozone (O(3)) were measured over a mixed temperate forest using the aerodynamic gradient method. The long-term average O(3) flux (F) was -366 ng m(-2) s(-1) for the period 2000-2010, corresponding to a...
Long-term fluxes of ozone (O(3)) were measured over a mixed temperate forest using the aerodynamic gradient method. The long-term average O(3) flux (F) was -366 ng m(-2) s(-1) for the period 2000-2010, corresponding to an average O(3) concentration of 48 μg m(-3) and a deposition velocity v(d) of 9 mm s(-1). Average nocturnal ozone deposition amounted to -190 ng m(-2) s(-1), which was about one third of the daytime flux. Also during the winter period substantial O(3) deposition was measured. In addition, total O(3) fluxes were found to differ significantly among canopy wetness categories. During the day, highest deposition fluxes were generally measured for a dry canopy, whereas a rain-wetted canopy constituted the best sink at night. Flux partitioning calculations revealed that the stomatal flux (F(s)) contributed 20% to the total F but the F(s)/F fraction was subject to seasonal and diurnal changes. The annual concentration-based index AOT40 (accumulated dose over a threshold of 40 ppb) and the Phytotoxic Ozone Dose (POD(1) or accumulated stomatal flux above a threshold of 1 nmol m(-2) s(-1)) were related in a curvilinear way. The O(3) deposition was found to be largely controlled by non-stomatal sinks, whose strength was enhanced by high friction velocities (u(*)), optimizing the mechanical mixing of O(3) into the canopy and the trunk space. The long-term geometrical mean of the non-stomatal resistance (R(ns)) was 136 s m(-1) but lower R(ns) values were encountered during the winter half-year due to higher u(*). The R(ns) was also subject to a marked diurnal variability, with low R(ns) in the morning hours, when turbulence took off. We speculate that non-stomatal deposition was largely driven by scavenging of ozone by biogenic volatile organic compounds (BVOCs) and especially NO emitted from the crown or the forest floor.
Environmental digest.
J Environ Monit · 2012 May · PMID 22618471 · Publisher ↗
Abstract loading — click title to view on PubMed.
Combined toxicity of three chlorophenols 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol to Daphnia magna.
Xing L, Sun J, Liu H … +1 more , Yu H
J Environ Monit · 2012 May · PMID 22618410 · Publisher ↗
The toxicity of single and combined mixtures of 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) to Daphnia magna was studied. The toxicity ranking of these three single chloro...
The toxicity of single and combined mixtures of 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) to Daphnia magna was studied. The toxicity ranking of these three single chlorophenols (CPs) to Daphnia magna was PCP > 2,4-DCP > 2,4,6-TCP. The toxic units (TU) approach was used to estimate the combined effects in experiments, the median effective concentration (EC(50)) values were 0.87-1.21 and 0.46-0.59 for binary and ternary mixtures, respectively. Response surface models of General Linear Models (R(2) > 0.90, residual deviation < 3.25) were established for all three binary mixtures. The toxicity for ternary mixtures based on the EC(50)-value and 10% effective concentration (EC(10))-value fixed mixture ratio presented a synergism. The risk based on the single CP's toxicity test may be underestimated. In addition, four approaches (concentration addition, toxicity equivalency factors, effect summation, and independent action) were used for the calculation of combined effects of the mixture. The experimental results showed that concentration addition and toxicity equivalency factor approaches were effective methods for calculation of additive effects of mixtures from binary systems of CPs; while independent action and effect summation (low simulated tail) predicted lower toxicity than experimental results. Limitations of the traditional focus on the effects of single agents were highlighted; hazard assessments ignoring the possibility of joint action of CPs will almost certainly lead to significant underestimations of risk.
Disinfection by-product formation potentials in wastewater effluents and their reductions in a wastewater treatment plant.
Tang HL, Chen YC, Regan JM … +1 more , Xie YF
J Environ Monit · 2012 May · PMID 22596061 · Publisher ↗
Disinfection by-product formation potentials (DBPFPs) in wastewater effluents from eight wastewater treatment plants (WWTPs) were investigated. In addition, a WWTP with one primary effluent and two different biological t...
Disinfection by-product formation potentials (DBPFPs) in wastewater effluents from eight wastewater treatment plants (WWTPs) were investigated. In addition, a WWTP with one primary effluent and two different biological treatment processes was selected for a comparative study. Formation potential tests were carried out to determine the levels of DBP precursors in wastewater. WWTPs that achieved better organic matter removal and nitrification tended to result in lower DBPFPs in effluents. For the WWTP with two processes, haloacetic acid, trihalomethane, and chloral hydrate precursors were predominant DBP precursors in the primary and secondary effluents. The percent reductions of haloacetonitrile and haloketone formation potentials averaged at 96% which was high in comparison to the reductions of other classes of DBPFPs. In addition, biological treatment changed the DBPFP speciation profile by lowering the HAAFP/THMFP ratio. The eight plant survey and the comparative analysis of the WWTP with two processes implied that besides nitrification, there may be other confounding factors impacting DBPFPs. Oxic and anoxic conditions, formation and degradation of soluble microbial products had impacts on the DBPFP reductions. This information can be used by water and wastewater professionals to better control wastewater-derived DBPs in downstream potable water supplies.
Source apportionment in oil spill remediation.
Muñoz J, Mudge SM, Loyola-Sepulveda R … +2 more , Muñoz G, Bravo-Linares C
J Environ Monit · 2012 May · PMID 22588176 · Publisher ↗
A pipe rupture during unloading led to a spillage of 350-700 tonnes of Caño Limon, a light sweet crude oil, into San Vicente Bay in 2007. Initial clean-up methods removed the majority of the oil from the sandy beaches al...
A pipe rupture during unloading led to a spillage of 350-700 tonnes of Caño Limon, a light sweet crude oil, into San Vicente Bay in 2007. Initial clean-up methods removed the majority of the oil from the sandy beaches although some oil remained on the rocky shores. It was necessary for the responsible party to clean the spilled oil even though at this location there were already crude oil hydrocarbons from previous industrial activity. A biosolvent based on vegetable oil derivatives was used to solubilise the remaining oil and a statistical approach to source apportionment was used to determine the efficacy of the cleaning. Sediment and contaminated rock samples were taken prior to cleaning and again at the same locations two days after application of the biosolvent. The oil was extracted using a modified USEPA Method 3550B. The alkanes were quantified together with oil biomarkers on a GC-MS. The contribution that Caño Limon made to the total oil hydrocarbons was calculated from a Partial Least Squares (PLS) analysis using Caño Limon crude oil as the source. By the time the biosolvent was applied, there had already been some attenuation of the oil with all alkanes <C(16) removed. After treatment, more of the mid-chain length compounds had been removed leading a skew towards the longer chain length compounds in the samples. The steranes provided a good indication of the source of the oil in this case and the contribution that Caño Limon made to the total oil ranged from 0% to 74%. The total hydrocarbon concentrations were lower after cleaning indicating an efficacy of 90% although the reduction in Caño Limon oil was smaller. This was sufficient to make further remediation unnecessary.
Polychlorinated biphenyls (PCBs) analysis using a miniaturized high-resolution time-of-flight mass spectrometer "MULTUM-S II".
Shimma S, Miki S, Toyoda M
J Environ Monit · 2012 May · PMID 22588150 · Publisher ↗
In this study, we conducted polychlorinated biphenyls (PCBs) analysis using fast gas chromatography (GC)/high-resolution mass spectrometry (HRMS). Mass spectrometry (MS) was performed with a miniature multi-turn time-of-...
In this study, we conducted polychlorinated biphenyls (PCBs) analysis using fast gas chromatography (GC)/high-resolution mass spectrometry (HRMS). Mass spectrometry (MS) was performed with a miniature multi-turn time-of-flight (TOF) analyzer called "MULTUM-S II". MULTUM-S II is truly a portable high resolution mass spectrometer. The mass spectrometer's high resolution capability is due to its theoretical infinite flight path utilizing perfect space and time focusing within a closed flight orbit. Mass resolution above 10 000 was easily achievable employing this portable system. This mass resolution is comparable to magnetic sector mass spectrometers, which have traditionally performed PCB analyses in the past. At a resolution of 10 000, a limit-of-detection of 1 ppb was determined using a heptachlorinated biphenyl standard sample. Using this fast GC/HRMS, 66 PCB congeners were analyzed within 5 min. In addition experiments aimed at confirming interference of PCB signal peaks and matrix peaks in diluted dielectric coolant fluids were performed. We found that the PCB signal peaks were detected without matrix interference via high mass resolution.
Assessing the impact of chloroacetanilide herbicides and their metabolites on periphyton in the Leyre River (SW France) via short term growth inhibition tests on autochthonous diatoms.
Roubeix V, Fauvelle V, Tison-Rosebery J … +3 more , Mazzella N, Coste M, Delmas F
J Environ Monit · 2012 May · PMID 22588122 · Publisher ↗
The Leyre River is the main tributary to the Bassin d'Arcachon lagoon. Herbicides belonging to the chloroacetanilide class have been found in the river (S-metolachlor and acetochlor) as well as some of their metabolites...
The Leyre River is the main tributary to the Bassin d'Arcachon lagoon. Herbicides belonging to the chloroacetanilide class have been found in the river (S-metolachlor and acetochlor) as well as some of their metabolites at higher concentrations. As the environmental toxicity of these molecules is not well known, ecotoxicological tests have been carried out on river periphyton at different levels of biological diversity: from the clone of one diatom species (Nitzschia nana) to the population of the same species (several clones) up to the multi-specific species community dominated by diatoms. Moreover, tests were performed on diatoms coming from an unpolluted upstream site and from a contaminated downstream site, in order to investigate possible tolerance acquisition to pollutants. The method consisted in measuring diatom growth inhibition at different doses of each substance from the increase of chlorophyll-a concentration after 4 days. It resulted that acetochlor was clearly more toxic than S-metolachlor at all levels of biological diversity. EC(50) values estimated from the tests suggest no effect of contaminants on diatom growth or biomass in the river. The toxicity of the metabolites appeared very low compared to that of their parent compounds. No difference in tolerance to the herbicides was demonstrated between summer diatom communities from the two sites in spite of different specific compositions. However, concerning the populations of N. nana isolated in winter following the highest herbicide concentrations in the river (about 0.5 μg L(-1)), the downstream population showed a higher tolerance to acetochlor but there was no co-tolerance to S-metolachlor. Thus, it appeared that acetochlor represents the highest toxic pressure on periphyton among the other contaminants in the Leyre River.
Enhancement effect of two ecological earthworm species (Eisenia foetida and Amynthas robustus E. Perrier) on removal and degradation processes of soil DDT.
Lin Z, Li XM, Li YT … +3 more , Huang DY, Dong J, Li FB
J Environ Monit · 2012 May · PMID 22584803 · Publisher ↗
Effects of two ecological earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus E. Perrier) with different densities (15 and 30 individuals per kg of soil) on the removal of soil 1,1,1-trichloro-2,2-b...
Effects of two ecological earthworm species (epigeic Eisenia foetida and endogeic Amynthas robustus E. Perrier) with different densities (15 and 30 individuals per kg of soil) on the removal of soil 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) with two pollution levels (2 and 4 mg kg(-1)) were investigated. Concentrations of DDT and its metabolites, including 1,1-dichloro-2,2-bis(4-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDE), and 1-chloro-2,2-bis(4-chlorophenyl)ethylene (DDMU), were monitored after 60, 180, and 360 days of incubation. The results obtained showed that both earthworm species can significantly enhance degradation of soil DDT to its metabolites. For E. foetida, the higher earthworm density showed significantly higher rate of DDT degradation than the lower one. Anaerobic reductive dechlorination was the main degradation pathway over 180 days of incubation, while the aerobic dechlorination process was promoted between 180 and 360 days of incubation. Some earthworm amended treatments showed significantly higher microbial biomass carbon and nitrogen than the control, which suggested that earthworms might enhance the microbial degradation of DDT. Both earthworm species would have the potential to be applied to enhance the remediation of agricultural lands polluted by DDT.
Distribution and risk assessment of organochlorine contaminants in surface water from River Chenab, Pakistan.
Eqani SA, Malik RN, Katsoyiannis A … +4 more , Zhang G, Chakraborty P, Mohammad A, Jones KC
J Environ Monit · 2012 May · PMID 22581020 · Publisher ↗
Concentrations in surface waters (including particulate phase) of the River Chenab ranged from 27-1100 ng L(-1) and 25-1200 ng L(-1) for OCPs and 7.7-110 ng L(-1) and 13-99 ng L(-1) for PCBs during summer and winter, res...
Concentrations in surface waters (including particulate phase) of the River Chenab ranged from 27-1100 ng L(-1) and 25-1200 ng L(-1) for OCPs and 7.7-110 ng L(-1) and 13-99 ng L(-1) for PCBs during summer and winter, respectively from 2007-2009. DDTs exhibited the highest concentration, followed by HCHs > chlordane > ∑(24)PCBs > ∑other OCPs. Different indicative ratios for organochlorines suggest that current use, long range transport and also past application of these chemicals contribute to the total burden. Statistical analysis highlighted agricultural and industrial activities and municipal waste disposal as main sources of OCPs and PCBs in the riverine ecosystem of the River Chenab. Risk Quotients (RQ(CCCs)) > 10 for DDTs and PCBs levels in collected water samples from the River Chenab suggest that risk from DDTs and PCBs is moderate to severe and fluxes calculated for OCPs and PCBs from the River Chenab to the Indus River were 7.5 tons per year and 1.0 tons per year, respectively.
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