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Monitoring air quality can help for lakes excessive proliferation of phytoplankton control
2021
Zhang, Chengxiang | Pei, Hongcui | Liu, Cunqi | Wang, Wei | Lei, Guangchun
Previous studies assessing excessive proliferation of phytoplankton (EPP) in lakes are generally based on single investigation and focused on limited environmental factors; meanwhile, less attention has been paid to lakes susceptibility to EPP. Here, we identify the priority of lakes for EPP control in a basin by assessing EPP in multiple lakes and identify the key factors related to lakes’ vulnerability to EPP. Field measurements, as well as multi-source survey data acquisition were conducted for 63 shallow lakes in the middle-lower Yangtze River basin. Resource-use efficiency by phytoplankton (RUE) was then used to represent lake susceptibility to EPP. Generalized linear models were used to assess the relative importance of environmental factors for RUE. We found that most lakes (76.19 %) were not suitable for recreation, due to health concern attributed to irritative or allergenic risk caused by EPP. Phosphorus was the primary limiting nutrient for EPP (74.60 % of lakes) which should be limited to < 0.09 mg/L. The linear model that included latitude, particulate matter 10, and precipitation explained 27.60 % of the variation of RUETP among lakes. In contrast, the linear model that included ozone, Secchi depth, and wind speed explained 19.41 % of the variation of RUETN among lakes. The key factor related to RUETP and RUETN was particulate matter 10 and ozone, respectively, both of which potentially increase RUE or reflect it. Our results suggest that integrating multiple survey datasets is critical for lakes EPP assessment in a basin, while lakes impacted by air pollution are a high priority for EPP control.
Show more [+] Less [-]An integrated modelling approach to derive the grey water footprint of veterinary antibiotics
2021
Wöhler, Lara | Brouwer, Pieter | Augustijn, Denie C.M. | Hoekstra, Arjen Y. | Hogeboom, Rick J. | Irvine, Brian | Lämmchen, Volker | Niebaum, Gunnar | Krol, Maarten S.
Water pollution by veterinary antibiotics (VAs) resulting from livestock production is associated with severe environmental and human health risks. While upward trends in global animal product consumption signal that these risks might exacerbate toward the future, VA related water pollution is currently insufficiently understood. To increase this understanding, the present research assesses processes influencing VA pollution from VA administration to their discharge into freshwater bodies, using an integrated modelling approach (IMA). For the VAs amoxicillin, doxycycline, oxytetracycline, sulfamethazine, and tetracycline we estimate loads administered to livestock, excretion, degradation during manure storage, fate in soil and transport to surface water. Fate and transport are modelled using the VA transport model (VANTOM), which is fed with estimates from the Pan-European Soil Erosion Risk Assessment (PESERA). The grey water footprint (GWF) is used to indicate the severity of water pollution in volumetric terms by combining VA loads and predicted no effect concentrations. We apply our approach to the German-Dutch Vecht river catchment, which is characterized by high livestock densities. Results show a VA mass load decrease larger than 99% for all substances under investigation, from their administration to surface water emission. Due to metabolization in the body, degradation during manure storage and degradation in soil, VA loads are reduced by 45%, 80% and 90% on average, respectively. While amoxicillin and sulfamethazine dissipate quickly after field application, significant fractions of doxycycline, oxytetracycline and tetracycline accumulate in the soil. The overall Vecht catchment's GWF is estimated at 250,000 m³ yr⁻¹, resulting from doxycycline (81% and 19% contribution from the German and Dutch catchment part respectively). Uncertainty ranges of several orders of magnitude, as well as several remaining limitations to the presented IMA, underscore the importance to further develop and refine the approach.
Show more [+] Less [-]Strong temporal and spatial variation of dissolved Cu isotope composition in acid mine drainage under contrasted hydrological conditions
2020
Masbou, J. | Viers, J. | Grande, J.-A. | Freydier, R. | Zouiten, C. | Seyler, P. | Pokrovsky, O.S. | Behra, P. | Dubreuil, B. | de la Torre, M.-L.
Copper export and mobility in acid mine drainage are difficult to understand with conventional approaches. Within this context, Cu isotopes could be a powerful tool and here we have examined the relative abundance of dissolved (<0.22 μm) Cu isotopes (δ⁶⁵Cu) in the Meca River which is an outlet of the Tharsis mine, one of the largest abandoned mines of the Iberian Pyrite Belt, Spain. We followed the chemical and isotopic composition of the upstream and downstream points of the catchment during a 24-h diel cycle. Additional δ⁶⁵Cu values were obtained from the tributary stream, suspended matter (>0.22 μm) and bed sediments samples. Our goals were to 1) assess Cu sources variability at the upstream point under contrasted hydrological conditions and 2) investigate the conservative vs. non conservative Cu behavior along a stream. Average δ⁶⁵Cu values varied from −0.47 to −0.08‰ (n = 9) upstream and from −0.63 to −0.31‰ downstream (n = 7) demonstrating that Cu isotopes are heterogeneous over the diel cycle and along the Meca River. During dry conditions, at the upstream point of the Meca River the Cu isotopic composition was heavier which is in agreement with the preferential release of heavy isotopes during the oxidative dissolution of primary sulfides. The more negative values obtained during high water flow are explained by the contribution of soil and waste deposit weathering. Finally, a comparison of upstream vs. downstream Cu isotope composition is consistent with a conservative behavior of Cu, and isotope mass balance calculations estimate that 87% of dissolved Cu detected downstream originate from the Tharsis mine outlet. These interpretations were supported by thermodynamic modelling and sediment characterization data (X-ray diffraction, Raman Spectroscopy). Overall, based on contrasted hydrological conditions (dry vs flooded), and taking the advantage of isotope insensitivity to dilution, the present work demonstrates the efficiency of using the Cu isotopes approach for tracing sources and processes in the AMD regions.
Show more [+] Less [-]Arsenic, chromium, and other elements of concern in fish from remote boreal lakes and rivers: Drivers of variation and implications for subsistence consumption
2020
Lescord, Gretchen L. | Johnston, Thomas A. | Heerschap, Matthew J. | Keller, W (Bill) | Southee, F Meg | O’Connor, Constance M. | Dyer, Richard D. | Branfireun, Brian A. | Gunn, John M.
Eating fish provides numerous health benefits, but it is also a dominant pathway for human exposure to contaminants. Many studies have examined mercury (Hg) accumulation in fish, but fewer have considered other elements, such as arsenic (As) and chromium (Cr). Recently, freshwater fish from several pristine boreal systems across northern Ontario, Canada, have been reported with elevated concentrations of As and Cr for reasons that are not well understood. Our goal was to investigate the ecological and environmental influences over concentrations of As, Cr, and other elements in these fish to better understand what affects metal uptake and the risk to consumers. We measured 10 elements (including As, Cr, Hg) as well as carbon (δ¹³C), nitrogen (δ¹⁵N), and sulfur (δ³⁴S) stable isotopes in 388 fish from 25 lake and river sites across this remote region. These data were used to determine the effect of: 1) trophic ecology; and 2) watershed geology on piscine elemental content. Overall, most element concentrations were low, often below provincial advisory benchmarks (ABs). However, traces of Hg, As, Cr, and selenium (Se) were detected in most fish. Based on their exceedance of their respective ABs, the most restrictive elements on fish consumption in these boreal systems were Hg > As > Cr. Arsenic and Se, but not Cr concentrations were related to fish size and trophic ecology (inferred from δ¹³C and δ¹⁵N), suggesting bioaccumulation of the former elements. Fish with enriched δ³⁴S values, suggestive of anadromous behaviour, had marginally lower Hg but higher Se concentrations. Modeling results suggested a strong effect of site-specific factors, though we found weak trends between piscine elemental content and geological features (e.g., mafic intrusions), potentially due to the broad spatial scale of this study. Results from this study address gaps in our understanding of As and Cr bioaccumulation and will help to inform fish consumption guidelines.
Show more [+] Less [-]Occurrence of caffeine in the freshwater environment: Implications for ecopharmacovigilance
2020
Li, Shulan | Wen, Jing | He, Bingshu | Wang, Jun | Hu, Xianmin | Liu, Juan
Owing to the substantial consumption of caffeinated food, beverages, and medicines worldwide, caffeine is considered the most representative pharmaceutically active compound (PhAC) pollutant based on its high abundance in the environment and its suitability as an indicator of the anthropogenic inputs of PhACs in water bodies. This review presents a worldwide analysis of 132 reports of caffeine residues in freshwater environments. The results indicated that more than 70% of the studies reported were from Asia and Europe, which have densely populated and industrially developed areas. However, caffeine pollution was also found to affect areas isolated from human influence, such as Antarctica. In addition, the maximum concentrations of caffeine in raw wastewater, treated wastewater, river, drinking water, groundwater, lake, catchment, reservoir, and rainwater samples were reported to be 3.60 mg/L, 55.5, 19.3, 3.39, 0.683, 174, 44.6, 4.87, and 5.40 μg/L, respectively. The seasonal variation in caffeine residues in the freshwater environment has been demonstrated. In addition, despite the fact that there was a small proportion of wastewater treatment plants in which the elimination rates of caffeine were below 60%, wastewater treatment is generally believed to have a high caffeine removal efficiency. From a pharmacy perspective, we proposed to adopt effective measures to minimize the environmental risks posed by PhACs, represented by caffeine, through a new concept known as ecopharmacovigilance (EPV). Some measures of EPV aimed at caffeine pollution have been advised, as follows: improving knowledge and perceptions about caffeine pollution among the public; listing caffeine as a high-priority PhAC pollutant, which should be targeted in EPV practices; promoting green design and production, rational consumption, and environmentally preferred disposal of caffeinated medicines, foods, and beverages; implementing intensive EPV measures in high-risk areas and during high-risk seasons; and integrating EPV into wastewater treatment programs.
Show more [+] Less [-]Analysis of pesticide mixtures discharged to the lagoon of the Great Barrier Reef, Australia
2020
Organisms and ecosystems are generally exposed to mixtures of chemicals rather than to individual chemicals, but there have been relatively few detailed analyses of the mixtures of pesticides that occur in surface waters. This study examined over 2600 water samples, analysed for between 21 and 47 pesticides, from 15 waterways that discharge to the lagoon of the Great Barrier Reef in Queensland, Australia between July 1, 2011 and June 30, 2015. Essentially all the samples (99.8%) contained detectable concentrations (>limit of detection) of pesticides and pesticide mixtures. Approximately, 10% of the samples contained no quantifiable (>limit of reporting) pesticides, 10% contained one quantifiable pesticide and 80% contained quantifiable mixtures of 2–20 pesticides. Approximately 82% of samples that contained quantifiable mixtures had more than two modes of action (MoAs), but only approximately 6% had five or more MoAs. The mode, average and median number of quantifiable pesticides in all the samples were 2, 5.1 and 4, respectively. The most commonly detected compounds both individually and in mixtures were the pesticides atrazine, diuron, imidacloprid, hexazinone, 2,4-D, and the degradation product desethylatrazine. The number of pesticides and modes of action of pesticides in mixtures differed spatially and were affected by land use. Waterways draining catchments where sugar cane was a major land use had mixtures with the most pesticides.
Show more [+] Less [-]Use of water quality index and multivariate statistical methods for the evaluation of water quality of a stream affected by multiple stressors: A case study
2020
Varol, Memet
The Sürgü Stream, located in the Euphrates River basin of Turkey, is used for drinking water source, agricultural irrigation and rainbow trout production. Therefore, water quality of the stream is of great importance. In this study, multivariate statistical techniques (MSTs) and water quality index (WQI) were applied to assess water quality of the stream affected by multiple stressors such as untreated domestic sewage, effluents from fish farms, agricultural runoff and streambank erosion. For this, 16 water quality parameters at five sites along the stream were monitored monthly during one year. Most of parameters showed significant spatial variations, indicating the influence of anthropogenic activities. All parameters except TN (total nitrogen) showed significant seasonal differences due to high seasonality in WT (water temperature) and water flow. The spatial variations in the WQI were significant (p < 0.05) and the mean WQI values ranged from 87.6 to 95.3, indicating “good” to “excellent” water quality in the stream. Cluster analysis classified five sites into three groups, that is, clean region, low polluted region and very clean region. Stepwise temporal discriminant analysis (DA) identified that pH, WT, Cl⁻, SO₄²⁻, COD (chemical oxygen demand), TSS (total suspended solids) and Ca²⁺ are the parameters responsible for variations between seasons, and stepwise spatial DA identified that DO (dissolved oxygen), EC (electrical conductivity), NH₄–N, TN (total nitrogen) and TSS are the parameters responsible for variations between the regions. Principal component analysis/factor analysis revealed that the parameters responsible for water quality variations were mainly associated with suspended solids (both natural and anthropogenic), soluble salts (natural) and nutrients and organic matter (anthropogenic).
Show more [+] Less [-]Spatial patterns of mesoplastics and coarse microplastics in floodplain soils as resulting from land use and fluvial processes
2020
Weber, Collin Joel | Opp, Christian
Plastic, and especially microplastic, contamination of soils has become a novel research field. After the detection of microplastics in soils, spatial distribution and dynamics are still unknown. However, the potential risks associated with plastic particles in soils cannot be sufficiently assessed without knowledge about the spatial distribution of these anthropogenic materials. Based on a spatial research approach, including soil surveys, this study quantified the mesoplastic (MEP, > 5.0 mm) and coarse microplastics (CMP, 2.0–5.0 mm) content of twelve floodplain soils. At four transects in the catchment area of the Lahn river (Germany), soils down to a depth of 2 m were examined for plastic content for the first time. MEP and CMP were detected through visual examination after sample preprocessing and ATR-FTIR analyses. Average MEP and CMP concentrations range between 2.06 kg⁻¹ (±1.55 kg⁻¹) and 1.88 kg⁻¹ (±1.49 kg⁻¹) with maximal values of 5.37 MEP kg⁻¹ to 8.59 CMP kg⁻¹. Plastic particles are heterogeneously distributed in samples. Both plastic size classes occur more frequently in topsoils than in soil layers deeper than 30 cm. The maximal depth of CMP occurrence lies between 75 and 100 cm. Most common CMP polymer type was PE-LD, followed by PP and PA. MEP and CMP particles occur frequently at near channel sides and more often on riparian strips or grassland than on farmland. Vertical distribution of CMP indicates anthropogenic relocation in topsoils and additional deep displacement through natural processes like preferential flow paths or bioturbation. By comparing sedimentation rates of the river with the maximum age of plastic particles, sedimentation as a deposition process of plastic in floodplains becomes probable. From our findings, it can be concluded that an overall widespread but spatial heterogenous contamination occurs in floodplain soils. Additionally, a complex plastic source pattern seems to appear in floodplain areas.
Show more [+] Less [-]Occurrence and assessment of environmental risks of endocrine disrupting compounds in drinking, surface and wastewaters in Serbia
2020
Čelić, Mira | Škrbić, Biljana D. | Insa, Sara | Živančev, Jelena | Gros, Meritxell | Petrović, M. (Mira)
The present study is the first comprehensive monitoring of 13 selected endocrine disrupting compounds (EDCs) in untreated urban and industrial wastewater in Serbia to assess their impact on the Danube River basin and associated freshwaters used as sources for drinking water production in the area. Results showed that natural and synthetic estrogens were present in surface and wastewater at concentrations ranging from 0.1 to 64.8 ng L⁻¹. Nevertheless, they were not detected in drinking water. For alkylphenols concentrations ranged from 1.1 to 78.3 ng L⁻¹ in wastewater and from 0.1 to 37.2 ng L⁻¹ in surface water, while in drinking water concentrations varied from 0.4 to 7.9 ng L⁻¹. Bisphenol A (BPA) was the most abundant compound in all water types, with frequencies of detection ranging from 57% in drinking water, to 70% in surface and 84% in wastewater. Potential environmental risks were characterized by calculating the risk quotients (RQs) and the estrogenic activity of EDCs in waste, surface and drinking water samples, as an indicator of their potential detrimental effects. RQ values of estrone (E1) and estradiol (E2) were the highest, exceeding the threshold value of 1 in 60% of wastewater samples, while in surface water E1 displayed potential risks in only two samples. Total estrogenic activity (EEQₜ) surpassed the threshold of 1 ng E2 L⁻¹ in about 67% of wastewater samples, and in 3 surface water samples. In drinking water, EEQₜ was below 1 ng L⁻¹ in all samples.
Show more [+] Less [-]Assessment of parameter uncertainty for non-point source pollution mechanism modeling: A Bayesian-based approach
2020
Xueman, Yan | Wenxi, Lu | Yongkai, An | Weihong, Dong
Uncertainty assessment of parameters associated with non-point source pollution mechanism modeling are crucial for improving the effectiveness of pollution controlling. In this study, an approach based on Bayesian inference and integrated Markov chain Monte Carlo and multilevel factorial analysis has been developed, and it can not only apply straightforward Bayesian inference to assess parameter uncertainties, but also quantitatively investigate the main and interactive effects of multiple parameters on the model response variables by measuring the specific variations of model outputs. Its applicability and advantages are presented through the application of the Soil and Water Assessment Tool to Shitoukoumen Reservoir Catchment in northeast China. This study investigated the uncertainties of a set of sensitive parameters and their multilevel effects on model response variables, including average annual runoff (AAR), average annual sediment (AAS) and average annual total nitrogen (AAN). Results revealed that (i) soil conservation service runoff curve number for moisture condition II (CN2) had a positive effect on all response variables; (ii) available water capacity of the soil layer (SOL_AWC) had a negative effect on all response variables; (iii) the universal soil loss equation support practice (USLE_P) had a positive effect on AAS and AAN, and little effect on AAR; while the nitrate percolation coefficient (NPERCO) had a positive effect on AAN, and little effect on AAS and AAR; and (iv) the interactions amongst parameters had obvious interdependent effects on the model response variables, for example, the interaction between CN2 and SOL_AWC had a major impact on AAR. The above findings can improve the simulating and predicting capabilities of non-point source pollution mechanism model. Overall, this study highlights that the proposed approach represents a promising solution for uncertainty assessment of model parameters in non-point source pollution mechanism modeling.
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