Journal Of Environmental Monitoring[JOURNAL]
Sun
200 papers
High-frequency phosphorus monitoring of the River Kennet, UK: are ecological problems due to intermittent sewage treatment works failures?
Bowes MJ, Palmer-Felgate EJ, Jarvie HP … +4 more , Loewenthal M, Wickham HD, Harman SA, Carr E
J Environ Monit · 2012 Dec · PMID 23104042 · Publisher ↗
The River Kennet in southern England has exhibited excessive benthic algal growth and associated ecological problems, such as loss of macrophytes and invertebrates, since the 1980s. These ecological problems were attribu...
The River Kennet in southern England has exhibited excessive benthic algal growth and associated ecological problems, such as loss of macrophytes and invertebrates, since the 1980s. These ecological problems were attributed to regular peaks in phosphorus concentration, which were widely attributed to intermittent failures of the Marlborough sewage treatment works (STW). This study deployed high-frequency phosphorus auto-analysers to monitor the total reactive phosphorus (TRP) concentrations of Marlborough STW final effluent and the downstream River Kennet at hourly and 30 minute resolution respectively, between 2008 and 2009. This monitoring confirmed that the Marlborough STW was operating well within its 1000 μg l⁻¹ annual mean total phosphorus consent limit, with mean total P and soluble reactive P concentrations of 675 and 345 μg l⁻¹ respectively. There were two occasions where effluent TRP concentration exceeded 1000 μg l⁻¹, and only one of these resulted in a peak in TRP concentration of over 100 μg l⁻¹ in the River Kennet at Mildenhall. The other nine peaks of over 100 μg l⁻¹ in the River Kennet during the monitoring period were associated with storm events, indicating that diffuse-source inputs and remobilisation of stored within-channel phosphorus were the cause of the peaks in river concentration, rather than Marlborough STW. The value of high-frequency environmental monitoring and the problems associated with using nutrient auto-analysers in the field are discussed. Seasonal phosphorus consents for STWs could provide a useful and cost effective means to improve both water quality and river ecology in the upper River Kennet.
Dynamic groundwater monitoring networks: a manageable method for reviewing sampling frequency.
Moreau-Fournier MF, Daughney CJ
J Environ Monit · 2012 Dec · PMID 23104002 · Publisher ↗
Optimization of a water quality network through a change in sampling frequency is the only way to increase cost-efficiency without any reduction in the robustness of the data. Existing techniques define optimal sampling...
Optimization of a water quality network through a change in sampling frequency is the only way to increase cost-efficiency without any reduction in the robustness of the data. Existing techniques define optimal sampling frequency based on analysis of historical data from the monitoring network under investigation. Their application to a large network comprised of many sites and many monitored parameters is both technical and challenging. This paper presents a simple non-parametric method for reviewing sampling frequency that is consistent with highly censored environmental data and oriented towards reduction of sampling frequency as a cost-saving measure. Based on simple descriptive statistics, the method is applicable to large networks with long time series and many monitored parameters. The method also provides metrics for interpretation of newly collected data, which enables identification of sites for which a future change in sampling frequency may be necessary, ensuring that the monitoring network is both current and adaptive. Application of this method to the New Zealand National Groundwater Monitoring Programme indicates that reduction of sampling frequency at any site would result in a significant loss of information. This paper also discusses the potential for reducing analysis frequency as an alternative to reduction of sampling frequency.
Coupling geostatistical approaches with PCA and fuzzy optimal model (FOM) for the integrated assessment of sampling locations of water quality monitoring networks (WQMNs).
Ou C, St-Hilaire A, Ouarda TB … +4 more , Conly FM, Armstrong N, Khalil B, Proulx-McInnis S
J Environ Monit · 2012 Dec · PMID 23103968 · Publisher ↗
The assessment of the adequacy of sampling locations is an important aspect in the validation of an effective and efficient water quality monitoring network. Two geostatistical approaches (e.g., kriging and Moran's I) ar...
The assessment of the adequacy of sampling locations is an important aspect in the validation of an effective and efficient water quality monitoring network. Two geostatistical approaches (e.g., kriging and Moran's I) are presented to assess multiple sampling locations. A flexible and comprehensive framework was developed for the selection of multiple sampling locations of multiple variables which was accomplished by coupling geostatistical approaches with principal component analysis (PCA) and fuzzy optimal model (FOM). The FOM was used in the integrated assessment of both multiple principal components and multiple geostatistical approaches. These integrated methods were successfully applied to the assessment of two independent water quality monitoring networks (WQMNs) of Lake Winnipeg, Canada, which respectively included 14 and 30 stations from 2006 to 2010.
Carcinogenic potential of soils contaminated with polycyclic aromatic hydrocarbons (PAHs) in Xiamen metropolis, China.
Cai C, Zhang Y, Reid BJ … +1 more , Nunes LM
J Environ Monit · 2012 Dec · PMID 23092998 · Publisher ↗
Xiamen is one of China's most rapidly developing metropolises. The objectives of the present study were: (1) to establish the levels and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in soil across the...
Xiamen is one of China's most rapidly developing metropolises. The objectives of the present study were: (1) to establish the levels and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in soil across the Xiamen metropolis, (2) to evaluate the extent to which PAH concentrations were elevated in the high urbanization area (HUA) of the island and how these compared with those in the low urbanization area (LUA) of the mainland, and (3) to evaluate the PAH hazard based upon their Carcinogenic Potential (CP), defined as toxicity equivalence of ∑PAHs. Twenty two alternative relative carcinogenic potency schemes were used and compared. Results demonstrated PAH concentrations to be greatly elevated across the entire metropolis. Significantly, the most enriched compounds represented the greatest concern with respect to carcinogenicity. The CP of more than 25% of the industrial samples from the island surpassed the Canadian guidance threshold value (600 μg kg⁻¹) for an excess lifetime cancer risk (ELCR) of 1 in 10⁻⁶. While soil samples from the remaining land uses on the island were all below this threshold, PAH levels in soil were nonetheless elevated (enrichment factors of between 4.1 ± 1.9 and 16.3 ± 12.4 in the HUA, and between 1.3 ± 0.7 and 10.8 ± 4.4 in the LUA). Results relating to agricultural locations on the island indicated 75% of the samples in HUA and 28% of the samples in LUA to be above the USEPA guidance value for BaP (15 μg kg⁻¹). Given the exceptionally high population density on the island there is a need for further research to evaluate multiple pathway PAH exposure risks.
Microscopic characterization of individual particles from multicomponent ship exhaust.
Popovicheva O, Kireeva E, Persiantseva N … +5 more , Timofeev M, Bladt H, Ivleva NP, Niessner R, Moldanová J
J Environ Monit · 2012 Dec · PMID 23090431 · Publisher ↗
Particles sampled from the main and auxiliary ship diesel engine exhausts during a measurement campaign aboard a cargo ship are studied by SEM and energy-dispersive X-ray (EDX) microanalysis. Cluster analysis (CA) is app...
Particles sampled from the main and auxiliary ship diesel engine exhausts during a measurement campaign aboard a cargo ship are studied by SEM and energy-dispersive X-ray (EDX) microanalysis. Cluster analysis (CA) is applied to characterize the particles by separating them into distinct groups of similar morphology and chemical composition, representative of the particle types in the exhaust from the main and auxiliary engines. Raman microspectroscopy, Fourier transform infrared (FTIR) spectroscopy, inductively coupled plasma mass spectrometry and ion chromatography provide the criteria for the clustering of a large data set of individual particles. To identify chemical and morphological features of heavy and distillate fuel oil-derived PM emissions, micromarkers discriminating between the different types of emitted particles are proposed. These micromarkers could enable the classification of multicomponent aerosols according to a source type. This characterization of complex multicomponent aerosols emitted by ship diesel engines improves the quantification of the contribution of shipping to ambient air particulates, and can help to identify a source type in apportionment studies.
Contamination, source, and input route of polycyclic aromatic hydrocarbons in historic wastewater-irrigated agricultural soils.
Wang N, Li HB, Long JL … +4 more , Cai C, Dai JL, Zhang J, Wang RQ
J Environ Monit · 2012 Dec · PMID 23072782 · Publisher ↗
Contamination by polycyclic aromatic hydrocarbons (PAHs) of historic wastewater-irrigated agricultural topsoil (0-5 cm) and the contribution of groundwater irrigation and atmospheric deposition to soil PAHs were studied...
Contamination by polycyclic aromatic hydrocarbons (PAHs) of historic wastewater-irrigated agricultural topsoil (0-5 cm) and the contribution of groundwater irrigation and atmospheric deposition to soil PAHs were studied in a typical agricultural region, i.e. Hunpu region, Liaoning, China. Concentrations of total PAHs ranged from 0.43 to 2.64 mg kg⁻¹ in topsoil, being lower than those found in other wastewater-irrigated areas. The levels of PAHs in soil declined as the distance from a water source increased. Concentrations of individual PAHs were generally higher in upland than in paddy topsoils. The calculated nemerow composite index showed that agricultural soil in the region was "polluted" by PAHs. A human health risk assessment based on the total toxic equivalent concentration showed that the presence of elevated concentrations of PAHs in the soil might pose a great threat to the health of local residents. Ratios of pairs of PAHs and principal component analysis (PCA) showed that pyrogenesis, such as coal combustion, was the main source of PAHs, while petroleum, to some extent, also had a strong influence on PAHs contamination in upland soil. The distribution patterns of individual PAHs and composition of PAHs differed between irrigation groundwater and topsoil, but were similar between atmospheric deposition and topsoil. There were significant linear correlations (r = 0.90; p < 0.01) between atmospheric deposition rates and average concentrations of the 16 individual PAHs in soils, while no significant relationships were observed between irrigation groundwater and topsoil in levels of PAHs. These suggested that PAHs in agricultural soils were mainly introduced from atmospheric deposition, rather than from groundwater irrigation after the phasing out of wastewater irrigation in the region since 2002. This study provides a reference to ensure agricultural product safety, pollution control, and proper soil management.
Impacts of mire reclamation on dynamics of dissolved nutrients in fluvial systems in the Sanjiang Plain, Northeast China.
Guo Y, Song C, Wang L … +1 more , Wan Z
J Environ Monit · 2012 Nov · PMID 23072759 · Publisher ↗
As an important nutrient reservoir, the mires in the Sanjiang Plain of Northeast China have been suffering from large-scale agriculture reclamation since the 1960s. The effects of the long-term reclamation on the dynamic...
As an important nutrient reservoir, the mires in the Sanjiang Plain of Northeast China have been suffering from large-scale agriculture reclamation since the 1960s. The effects of the long-term reclamation on the dynamics of the dissolved nutrients in fluvial systems are revealed through surveying the export concentrations of dissolved nitrogen and phosphorus in the natural mire, degraded mire and drainage ditches during the growing seasons in 2009 and 2010. The results show that the mean concentrations of total dissolved nitrogen (TDN, 2.03 ± 0.355 mg l(-1)) are much higher in natural mire than in degraded mire (1.15 ± 0.247 mg l(-1)) and ditches (1.03 ± 0.231 mg l(-1)), and the fraction lessened is primarily the organic part of nitrogen. It indicates that the long-term mire reclamation has led to a significant reduction in TDN concentrations in the surface fluvial system, and has changed the dominant nitrogen components from organic to inorganic formation. In comparison, the concentrations of total dissolved phosphorus (TDP) have no significant difference between natural mire and degraded mire or ditches, which demonstrates that mire reclamation has no impact on TDP export dynamics in the fluvial system. The seasonal dynamics of TDN are strongly correlated to dissolved organic carbon at almost all the sample sites, and mire reclamation does not alter the C : N ratio in the fluvial system, but lowers N : P ratio remarkably. The long-term reclamation exerts distinctly different effects on the export dynamics of TDN and TDP in the fluvial system in the Sanjiang Plain. Specific goals and methods ought to be determined if ecological management and recovery measures are to be carried out.
Identification and modelling the HRT distribution in subsurface constructed wetland.
Cui L, Zhang Y, Zhang M … +4 more , Li W, Zhao X, Li S, Wang Y
J Environ Monit · 2012 Nov · PMID 23064726 · Publisher ↗
This study focused on the identification of the hydrodynamics of a horizontal subsurface constructed wetland (HSSF-CW) located in Beijing wildlife rescue and rehabilitation center, Beijing. The effects of plant growth of...
This study focused on the identification of the hydrodynamics of a horizontal subsurface constructed wetland (HSSF-CW) located in Beijing wildlife rescue and rehabilitation center, Beijing. The effects of plant growth of iris tectorum on the hydrodynamic behaviours were studied and the distribution of the hydraulic residence time was simulated by several mathematical models in order to understand the fluctuations and mixing processes of pollutants in the HSSF-CW. Treatment performance of the HSSF-CW was evaluated by comparing the area-based removal rates of different pollutants. According to the results, water depth has a negative effect on the plant growth and a larger hydraulic loading rate is not conducive to the growth of wetland plants. Modelling the probability density of the residence time distribution indicated that the shorter hydraulic residence time of 10.16 hours compared with a theoretical hydraulic residence time of 12.81 hours was responsible for the lower removal efficiency of pollutants (T-P: 0.17 ± 0.04 g m(-2) day(-1), T-N: 1.10 ± 0.05 g m(-2) day(-1), PO(4)-P: 0.08 ± 0.04 g m(-2) day(-1), NH(4)-N: 0.19 ± 0.02 g m(-2) day(-1), NO(3)-N: 0.52 ± 0.03 g m(-2) day(-1), Chl_a: 18.26 ± 0.09 g m(-2) day(-1)). The results of a superposition simulation of residence time distribution indicated that the asymmetric double sigmoidal (asym2sig) model is competent at providing a reasonable match between the measured and the predicted values to some extent. Based on the good fit of the experimental datasets by the asym2sig probability density function, the mathematical expectation approximated to the actual hydraulic residence time (10.16 hours) of the HSSF-CW.
Uptake of human pharmaceuticals and personal care products by cabbage (Brassica campestris) from fortified and biosolids-amended soils.
Holling CS, Bailey JL, Vanden Heuvel B … +1 more , Kinney CA
J Environ Monit · 2012 Nov · PMID 23051741 · Publisher ↗
Human pharmaceuticals and personal care products (PPCPs) are routinely found in biosolids from wastewater treatment plants (WWTPs). Once land applied, the PPCPs in biosolids are potentially available for plant uptake and...
Human pharmaceuticals and personal care products (PPCPs) are routinely found in biosolids from wastewater treatment plants (WWTPs). Once land applied, the PPCPs in biosolids are potentially available for plant uptake and bioaccumulation. This study used a greenhouse model to investigate uptake of PPCPs commonly detected in biosolids by the agricultural plant Chinese cabbage (Brassica campestris). Two series of greenhouse experiments were conducted as part of this project. In the first set of experiments, four pharmaceuticals were added to an organic matter-rich soil in environmentally relevant concentrations based on typical biosolids application rates, resulting in final soil concentrations of 2.6 ng g(-1) carbamazepine, 3.1 ng g(-1) sulfamethoxazole, 5.4 ng g(-1) salbutamol, and 0.5 ng g(-1) trimethoprim. In the second set of experiments, the cabbage was grown in soil amended with an agronomic rate of biosolids from a local WWTP. The ambient concentration of PPCPs in the biosolids resulted in final soil concentrations of 93.1 ng g(-1) carbamazepine, 67.4 ng g(-1) sulfamethoxazole, 30.3 ng g(-1) salbutamol, 433.7 ng g(-1) triclosan, and 24.7 ng g(-1) trimethoprim. After growing to maturity, the aerials of the plants were separated from roots and the two tissue types were analyzed separately. All four human pharmaceuticals were detected in both tissues in the cabbage grown in the soil fortified with the four pharmaceuticals with median concentrations of 255.4 ng g(-1) aerials and 272.9 ng g(-1) roots carbamazepine; 222.8 ng g(-1) aerials and 260.3 ng g(-1) roots sulfamethoxazole; 108.3 ng g(-1) aerials and 140.6 ng g(-1) roots salbutamol; and 20.6 ng g(-1) aerials and 53.7 ng g(-1) roots trimethoprim. Although all study compounds were present in the biosolids-amended planting soil, only carbamazepine (317.6 ng g(-1) aerials and 416.2 ng g(-1) roots), salbutamol (21.2 ng g(-1) aerials and 187.6 ng g(-1) roots), and triclosan (22.9 ng g(-1) aerials and 1220.1 ng g(-1) roots) were detected in the aerials of the cabbage. In addition to the study compounds detected in the aerials, sulfamethoxazole was detected in the roots of one of the plants in the biosolid-amended soil. In comparison to many previous studies that have utilized PPCP concentration that exceed environmentally relevant concentrations, plants in this study were exposed to environmentally relevant concentrations of the PPCPs, yet resulted in uptake concentrations similar to or greater than those reported in comparable studies. We suggest that rhizosphere conditions, particularly the presence of dissolved organic matter in the planting matrix, might be one of the critical factors determining mobilization and bioavailability of xenobiotic compounds such as PPCPs.
Regional variation in pesticide concentrations in plasma of delivering women residing in rural Indian Ocean coastal regions of South Africa.
Channa KR, Röllin HB, Wilson KS … +4 more , Nøst TH, Odland JØ, Naik I, Sandanger TM
J Environ Monit · 2012 Nov · PMID 23047303 · Publisher ↗
Exposure to pesticides places pregnant women and the developing foetus at the highest risk. The objective of this study is to obtain an exposure assessment by investigating levels of pesticides in blood plasma of deliver...
Exposure to pesticides places pregnant women and the developing foetus at the highest risk. The objective of this study is to obtain an exposure assessment by investigating levels of pesticides in blood plasma of delivering women. We report on the concentrations of α, β, γ HCH, endosulfan, HCB and the pyrethroids: cis-permethrin, cyfluthrin, cypermethrin and deltamethrin found in the maternal blood plasma of delivering women (n = 241) in three coastal sites of KwaZulu Natal. γ-HCH and endosulfan 1 and 2 were the most dominant pesticides in all three sites. Significantly, higher levels of γ-HCH and endosulfan were found in site 3 (vicinity of Empangeni) compared to the other two sites (p < 0.05). The GM levels for γ-HCH, endosulfan 1 and 2 were 956, 141 and 21 ng g(-1) lipids in site 3, respectively. The pyrethroid pesticides, HCB, α-HCH and β-HCH were detected in less than 31% of the samples in all sites. γ-HCH correlated positively and strongly to both endosulfan 1 and 2 (r > 0.47), indicating a common source of exposure. The high levels of γ-HCH and endosulfan in maternal plasma samples in site 3 indicate the current and on-going exposure, which is of great concern for reproductive health and prenatal exposure.
Dynamic interactions between cyclodextrin, an organic pollutant, and granular activated carbon in column studies.
Blanford WJ, Gao H
J Environ Monit · 2012 Nov · PMID 23042079 · Publisher ↗
In this study, the dynamic interactions between cyclodextrin (CD), an organic chemical and granular activated carbon (GAC) were investigated using column studies. Breakthrough curves of a chlorinated solvent, trichloroet...
In this study, the dynamic interactions between cyclodextrin (CD), an organic chemical and granular activated carbon (GAC) were investigated using column studies. Breakthrough curves of a chlorinated solvent, trichloroethylene (TCE) were obtained over a range of concentrations of 2-hydroxypropyl-beta-cyclodextrin (HPCD) (0, 20, and 50 g L(-1)) and flow velocities (1.0, 4.0, and 10.2 mL min(-1)). Important transport parameters (i.e. residence time, dispersion coefficient, retardation factor) were estimated using truncated temporal moment analysis. Our result shows that increasing CD concentration resulted in earlier TCE breakthrough, demonstrated by decreasing residence times which are 306.23, 151.26, and 102.24 pore volumes for 0, 20, and 50 g L(-1) CD respectively. Comparison of the original breakthrough curves (BTCs) under different CD concentrations to the solubility-enhancement-rescaled BTCs showed (1) the presence of CD decreases the relative degree of TCE sorption to GAC and (2) all 3 curves exhibited similar rescaled times at which they reach 50% of the input concentration. The lowest flow rate, (1.0 mL min(-1)), resulted in a more symmetrical BTC, indicating more ideal conditions were achieved under the longer exposure time provided by this flow rate. As the flow rate increases the first appearance of TCE in the eluent occurs relatively earlier and exhibits comparatively greater delay in achieving full breakthrough, suggesting non-equilibrium processes are more significant at higher flow rates.
Monitoring the occurrence of PAHs in Irish wastewater effluent.
Jones L, Kinsella B, Furey A … +1 more , Regan F
J Environ Monit · 2012 Nov · PMID 23034654 · Publisher ↗
Polycyclic aromatic hydrocarbons (PAHs) are commonly occurring environmental pollutants, 8 of which have been chosen from the list of priority substances in the EU Water Framework Directive (WFD). The levels of PAHs in t...
Polycyclic aromatic hydrocarbons (PAHs) are commonly occurring environmental pollutants, 8 of which have been chosen from the list of priority substances in the EU Water Framework Directive (WFD). The levels of PAHs in the environment are affected by a number of emission factors including anthropogenic activities, population equivalents, and weather, all of which must be taken into account when monitoring levels of PAHs being released into the environment via waste water treatment plant effluent. Effluent samples have been collected from nine different wastewater treatment plants in 2 areas of Ireland (Dublin and Cork) over a period of 3 years (2009-2011), including several weeks of high intensity sampling. Solid phase extraction is used in the sample preparation process with subsequent analysis by gas chromatography with mass spectrometric detection (GCMS). All samples analysed contained the priority PAHs in this study; however levels detected do not exceed environmental quality standards (EQSs). Herein these results are related to a number of key emission factors affecting the levels of PAHs present in wastewater treatment plant effluent. This study aims to complement storm water studies and inform future targeted priority substance monitoring programmes.
Study of indoor radon concentrations and associated health risks in the five districts of Hazara division, Pakistan.
Khan F, Ali N, Khan EU … +4 more , Khattak NU, Raja IA, Baloch MA, Rajput MU
J Environ Monit · 2012 Nov · PMID 23034598 · Publisher ↗
A total of 200 indoor air samples were collected to measure radon concentration levels and its contribution to the mean effective doses during different seasons of the period 2009-2010 at different sites of the five dist...
A total of 200 indoor air samples were collected to measure radon concentration levels and its contribution to the mean effective doses during different seasons of the period 2009-2010 at different sites of the five districts of Hazara division, Pakistan. The major portion of the region is mountainous and is full of thick forests which receives heavy snow fall in winter. The need for conducting the present survey relied on the fact that occupants spend their lives in poorly ventilated indoor environments of the region, especially in the winter season when they use wood fire inside their residences. The measurements of indoor air samples were taken with RAD-7, a solid state α-detector. Radon concentrations in the whole region range from 41 Bq m(-3) to 254 Bq m(-3) with a geometric mean of 128 Bq m(-3). Radon progenies were measured with a surface barrier detector through alpha spectroscopy from which the Equilibrium Factor (EF) for radon and Radon Decay Products (RDPs) for the smoke-bearing as well as smoke-free indoor environments were deduced. The respective mean values of EF were calculated as 0.49 ± 0.08 and 0.40 ± 0.07. The mean effective doses from indoor air of Abbottabad, Mansehra, Haripur, Battgram and Kohistan districts were calculated as 3.5 ± 1.2, 3.7 ± 0.7, 3.9 ± 1.0, 3.6 ± 1.1 and 3.9 ± 0.7 mSv a(-1) respectively, with the maximum value of 5.1 ± 1.8 mSv a(-1) in Kohistan district during winter and the minimum value of 2.9 ± 1.0 mSv a(-1) in Abbottabad district during summer. The annual exposure dose to the inhabitants of the locality lies below the upper bound of 10 mSv a(-1), as recommended by ICRP-65, and may not pose any significant threat to the public health.
Lead isotopes in marine surface sediments reveal historical use of leaded fuel.
Larsen MM, Blusztajn JS, Andersen O … +1 more , Dahllöf I
J Environ Monit · 2012 Nov · PMID 23032582 · Publisher ↗
Analyses of lead (Pb) isotopes have been performed in terrestrial and fresh water environments to estimate historical uses of leaded fuel, but so far this method has not been employed in studies of world-wide marine surf...
Analyses of lead (Pb) isotopes have been performed in terrestrial and fresh water environments to estimate historical uses of leaded fuel, but so far this method has not been employed in studies of world-wide marine surface sediments. We analyzed Pb and its isotopes in 23 surface sediments from four continents collected during the Galathea 3 expedition in 2006-2007. To enhance the anthropogenic signal, a partial digestion using nitric acid was performed. The concentrations of Pb, Th, U and Al were determined with an ICP-Quadrupole MS, and Pb-isotope ratios with an ICP-multi-collector MS. The samples could be divided into three groups: Harbor areas in larger cities with concentrations of 150 to 265 mg kg(-1) dry weight, smaller towns with concentrations between 20 and 40 mg kg(-1) dry weight, and remotely located sites with concentrations below 15 mg kg(-1) dry weight. Pb-isotope ratios were compared to literature values for gasoline and local or geological background values, and the contribution of leaded-gasoline to total concentrations was calculated for contaminated sites using both a one-dimensional and a novel two-dimensional (vector) method. The North American sites had Pb-isotope ratios corresponding to the US leaded gasoline, with 24-88% of the Pb from leaded gasoline. Samples from Oceania showed Pb-isotope ratios corresponding to Australian gasoline, with 60% attributed to leaded gasoline in Sydney and 21% in Christchurch. Outside Cape Town, 15 to 46% of Pb in sediments was from leaded gasoline.
Water quality assessment using the AREc32 reporter gene assay indicative of the oxidative stress response pathway.
Escher BI, Dutt M, Maylin E … +4 more , Tang JY, Toze S, Wolf CR, Lang M
J Environ Monit · 2012 Nov · PMID 23032559 · Publisher ↗
The reporter gene assay AREc32 is based on the induction of the Nrf2 mediated oxidative stress response pathway in the human breast cancer cell line MCF7, where eight copies of the antioxidant response element (ARE) are...
The reporter gene assay AREc32 is based on the induction of the Nrf2 mediated oxidative stress response pathway in the human breast cancer cell line MCF7, where eight copies of the antioxidant response element (ARE) are linked to a reporter gene encoding for luciferase. The Nrf2-ARE pathway is responsive to many chemicals that cause oxidative stress, among them a large number of pesticides and skin irritants. We adopted and validated the AREc32 bioassay for water quality testing. tert-Butylhydroquinone served as the positive control, phenol as the negative control and other reactive chemicals were assessed for their specificity. An environmentally relevant reference chemical, benzo(a)pyrene was the most potent inducer of all tested chemicals. The concentration causing an induction ratio (IR) of 1.5 (EC(IR1.5)) was chosen as the effect benchmark value. The assay was applied to 21 water samples ranging from sewage to drinking water, including secondary treatment and various tertiary treatment options (ozonation, biologically activated carbon filtration, membrane filtration, reverse osmosis, advanced oxidation, chlorination, chloramination). The samples were enriched by solid phase extraction. In most samples the oxidative stress response was far more sensitive than cytotoxicity. The primary and secondary treated effluent exceeded the effect threshold IR 1.5 at a relative enrichment factor (REF) of 1, i.e., the native samples were active. All tertiary treated samples were less potent and their EC(IR1.5) lay between REF 1 and 10. The Nrf2 pathway was induced at a REF of approximately 10 for surface waters and drinking water, and above this enrichment cytotoxicity took over in most samples and quenched the induction. The blank (ultrapure water run through the sample enrichment process) was cytotoxic at an REF of 100, which is the limit of concentrations range that can be evaluated. Treatment typically decreased both the cytotoxicity and oxidative stress response apart from drinking water treatment where chlorination caused an increase in oxidative stress response, presumably due to the formation of disinfection by-products. This study demonstrates the relevance and applicability of the oxidative stress response pathway for water quality monitoring.
Will stringent total nitrogen wastewater treatment plant discharge regulations achieve stream water quality goals?
Son JH, Carlson KH
J Environ Monit · 2012 Nov · PMID 23032438 · Publisher ↗
The Colorado Department of Public Health and Environment (CDPHE) proposed the in-stream numeric nutrient criteria as 2 mg TN per L and 0.16 mg TP per L for warm surface waters and 0.40 mg TN per L and 0.11 mg TP per L fo...
The Colorado Department of Public Health and Environment (CDPHE) proposed the in-stream numeric nutrient criteria as 2 mg TN per L and 0.16 mg TP per L for warm surface waters and 0.40 mg TN per L and 0.11 mg TP per L for cold surface waters. Consequently the department presented the nutrient limits for the municipal wastewater treatment plants (WWTPs) as annual averages of 0.7 mg TP per L and 5.7 mg TIN per L and quarterly averages of 1.0 mg TP per L and 9.0 mg TIN per L. Implementing stringent nutrient reduction at point sources is unlikely to result in improvements to the environment without non-point source controls. In this study, total nitrogen (TN) load inputs from known point source, WWTPs, and other non-point sources at six sub-basins of the Cache La Poudre (CLP) River Basin were estimated and compared under various hydrologic conditions. Significant loading exceedance from the proposed limits was observed during lower flow conditions and other sources dominated during events when the exceedance was observed except for one point. The point receives direct TN inputs from a WWTP which has the highest TN concentration in its effluent among all WWTPs in the study area; however, TN loads entered the point from other sources were significant during higher flow conditions. TN loads in the CLP River were simulated to determine whether the loads meet the proposed in-stream limits in a case in which all WWTPs comply with the proposed regulations for WWTPs. From this study, it was observed that reducing TN concentrations only at WWTPs merely impacts total TN loads in the river.
Phosphorus concentration and loading reductions following changes in fertilizer application and formulation on managed turf.
King KW, Balogh JC, Agrawal SG … +2 more , Tritabaugh CJ, Ryan JA
J Environ Monit · 2012 Nov · PMID 23026887 · Publisher ↗
Excess phosphorus, particularly in surface waters can lead to severe eutrophication. Identifying source areas, quantifying contributions, and evaluating management practices are required to address current and future wat...
Excess phosphorus, particularly in surface waters can lead to severe eutrophication. Identifying source areas, quantifying contributions, and evaluating management practices are required to address current and future water quality concerns. A before-after study was conducted from 2003-2010 on a sub-watershed of Northland Country Club Golf Course in Duluth, MN to demonstrate the impacts of two different phosphorus management approaches (Period 1: traditional application and timing using commercially available synthetic blends; Period 2: reduced rate, low dose applications, and organic formulations). Outflow median dissolved reactive phosphorus (DRP) and total phosphorus (TP) stream concentrations were significantly less in Period 2 compared to Period 1. There was no statistical difference in the mean TP loading in Period 1 (0.25 kg ha(-1) year(-1)) compared to Period 2 (0.20 kg ha(-1) year(-1)) or between the DRP loading in Period 1 (0.15 kg ha(-1) year(-1)) compared to Period 2 (0.09 kg ha(-1) year(-1)). However, by switching to organic phosphorus formulations and reducing application rates by greater than 75%, substantial reduction in DRP and TP concentrations was achieved. Based on these findings it is recommended that turf managers (parks and recreation to golf courses) explore the feasibility of altering their fertility management related to phosphorus by including organic formulations, low dose applications, and overall rate reductions. Additionally, it is recommended that the fertilizer industry develop and make more readily available commercial blends with lesser to zero amounts of phosphorus.
Chemical composition, sources, and deposition fluxes of water-soluble inorganic ions obtained from precipitation chemistry measurements collected at an urban site in northwest China.
Shen Z, Zhang L, Cao J … +7 more , Tian J, Liu L, Wang G, Zhao Z, Wang X, Zhang R, Liu S
J Environ Monit · 2012 Nov · PMID 23023835 · Publisher ↗
Precipitation samples were collected at an urban site in Xi'an, northwest China during March to November in 2009 and were then analyzed to determine the pH and concentrations of water-soluble inorganic ions (Na(+), NH(4)...
Precipitation samples were collected at an urban site in Xi'an, northwest China during March to November in 2009 and were then analyzed to determine the pH and concentrations of water-soluble inorganic ions (Na(+), NH(4)(+), K(+), Mg(2+), Ca(2+), SO(4)(2-), NO(3)(-), Cl(-), and F(-)) in precipitation. The pH of precipitation ranged from 4.1 to 7.6 for all of the samples with an annual volume-weighted mean of 6.4. While a large portion of the precipitation events were weakly acidic or alkaline, around 30% of the precipitation events in the autumn were strongly acidic. Precipitation events with air masses from the northeast and the southeast were weakly acidic while those with air masses from the northwest and the southwest were alkaline. SO(4)(2-), Ca(2+), NH(4)(+), and NO(3)(-) were dominant ions in the precipitation, accounting for 37%, 25%, 18%, and 9%, respectively, of the total analyzed ions. Ca(2+) and NH(4)(+) were found to be the major neutralizers of precipitation acidity; however, the contribution of Mg(2+), although much lower than those of Ca(2+) and NH(4)(+), was important, in many cases, in changing the precipitation from weakly acidic to weakly alkaline. Enrichment factor analysis confirmed that SO(4)(2-) and NO(3)(-) were produced from anthropogenic sources, Ca(2+), K(+), and 80% Mg(2+) were from crustal sources, and Na(+), Cl(-), and ∼20% of Mg(2+) were from marine sources. The annual wet depositions were estimated to be 3.5 t km(-2) per year for sulfur; 2.3 t km(-2) per year for nitrogen, of which 0.8 t km(-2) per year was oxidized nitrogen and 1.5 t km(-2) per year was reduced nitrogen; and 3.0 t km(-2) per year for Ca(2+).
Modeling volatilization and adsorption of disinfection byproducts in natural watersheds.
Jin W, Zhou J, Chen B … +2 more , Zhu X, Cui C
J Environ Monit · 2012 Nov · PMID 23018447 · Publisher ↗
It is an emerging concern that a series of disinfection byproducts (DBPs) produced in wastewater effluent have adversely impacted the downstream aquatic system and drinking water resources. The occurrence, fate, and tran...
It is an emerging concern that a series of disinfection byproducts (DBPs) produced in wastewater effluent have adversely impacted the downstream aquatic system and drinking water resources. The occurrence, fate, and transport of DBPs on receiving waterbodies, however, are currently not well-documented. To fill the knowledge gap, this study simulated the effects of volatilization and adsorption processes on the removals of DBPs (THM, HAA, HAN, HNM, and NA) in different types of watersheds (lake, stream, river, and aquifer). The effects of a series of variables, including hydrogeological characteristics (e.g., water depth, flow rate, roughness), environmental conditions (e.g., temperature, wind velocity), and chemical properties (e.g., octanol-water partition coefficient, Henry's law constant, molecular weight, density) were evaluated and their relative importance were compared. The results indicate that volatilization mechanism was preferred in the stream-type watershed and effective in reducing THMs, but unlikely to reduce HAAs. Adsorption and removal of DBPs on settling suspended solid in surface waters appears insignificant, accounting for less than 8% of the DBP content. Adsorption of DBPs on aquifer soil does not reduce DBPs directly; nonetheless, it reduces the mobility of DBPs in the aquifer and provides a place for other mechanisms to degrade/transform DBPs. The results of this study therefore may help understand the occurrence, fate, and risk of wastewater-derived DBPs in downstream waterbodies, and trigger more laboratory tests in the future to dedicate to the mechanisms and DBPs with significant impact.
Arsenobetaine formation in plankton: a review of studies at the base of the aquatic food chain.
Caumette G, Koch I, Reimer KJ
J Environ Monit · 2012 Nov · PMID 23014956 · Publisher ↗
Arsenobetaine is one of the major organoarsenic compounds found in aquatic organisms, including seafood and fish meant for human consumption. It has been widely studied over the last 50 years because of its non-toxic pro...
Arsenobetaine is one of the major organoarsenic compounds found in aquatic organisms, including seafood and fish meant for human consumption. It has been widely studied over the last 50 years because of its non-toxic properties, and its origin is postulated to be at bottom of the aquatic food chains. The present review focuses on arsenobetaine formation in marine and freshwater plankton, comparing the arsenic compounds found in the different plankton organisms, and the methods used to assess arsenic speciation. The main findings indicate that in the marine environment, phytoplankton and micro-algae contain arsenosugars, with the first traces of arsenobetaine appearing in herbivorous zooplankton, and becoming a major arsenic compound in carnivorous zooplankton. Freshwater plankton contains less arsenobetaine than their marine relatives, with arsenosugars dominating. The possible role and formation pathways of arsenobetaine in plankton organisms are reviewed and the literature suggests that arsenobetaine in zooplankton comes from the degradation of ingested arsenosugars, and is selectively accumulated by the organism to serve as osmolyte. Several arsenic compounds such as arsenocholine, dimethylarsinoylacetate or dimethylarsinoylethanol that are intermediates of this pathway have been detected in plankton. The gaps in research on arsenobetaine in aquatic environments are also addressed: primarily most of the conclusions are drawn on culture-based experiments, and few data are present from the natural environment, especially for freshwater ecosystems. Moreover, more data on arsenic in different zooplankton species would be helpful to confirm the trends observed between herbivorous and carnivorous organisms.
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