Receiving Water Bodies Research Articles

Chemometric Assessment of Bulgarian Wastewater Treatment Plants' Effluents.

Surface water quality strongly depends on anthropogenic activity. Among the main anthropogenic sources of this activity are the wastewater treatment plant (WWTP) effluents. The discharged loads of nutrients and suspended solids could provoke serious problems for receiving water bodies and significantly alter the surface water quality. This study presents inventory analysis and chemometric assessment of WWTP effluents based on the mandatory monitoring data. The comparison between the Bulgarian WWTPs and previously reported data from other countries reveals that discharged loads from investigated WWTPs are lower. This is particularly valid for total suspended solids (TSS). The low TSS loads are the reason for the deviations of the typical calculated WWTP effluent ratios of Bulgarian WWTPs compared to the WWTPs worldwide. The performed multivariate analysis reveals the hidden factors that determine the content of WWTP effluents. The source apportioning based on multivariate curve resolution analysis provides detailed information for source contribution profiles of the investigated WWTP effluent loads and elucidate the difference between WWTPs included in this study.

Assessment of deicing salt storage and distribution as a salinization point source: the influence of permitting standards on water quality

BackgroundRoad deicing salts are impacting freshwater ecosystems in snowy regions worldwide. Rock salt (typically sodium chloride) is transported to and stored in regional facilities that operate year-round and are continuous potential sources of chloride discharge to adjacent water bodies, resulting in different impacts to aquatic ecosystems than chloride pollution from spatially diffuse road networks. The regulatory tools and associated monitoring regimes used by state and federal agencies related to permitting of these facilities is inconsistent. Selection of the regulatory standards and monitoring location in the receiving water body (and how the definition of ‘receiving water body’ is applied) can have a significant influence on the measured or modeled impact of a facility on aquatic ecosystems. Additionally, selection of the monitored media (surface water, soil pore water, shallow ground water, or vegetation) can further influence findings, resulting in inconsistent conclusions of environmental impact and potentially allow exceedances of regulatory thresholds of chloride. This study evaluates chloride pollution from salt loading over two years from a state-permitted salt storage and transport facility in Shelburne, Vermont, USA to an adjacent wetland and river that drains to Lake Champlain. Water quality results and modeled assumptions made by the permittee were compared to monitoring data at two discharge points from the site including a drainage channel downstream of the site’s stormwater pond and at a shallow ground water seep below the rail car unloading area.ResultsResults indicate elevated chloride concentrations (average of 243 and 643 mg L−1) at the discharge points to the receiving water body, in conflict with findings from annual permittee assessments. Soil cores taken in the wetland in the vicinity of the control and two discharge points also indicate elevated Cl− (p ≤ 0.035) and Na+ (p ≤ 0.0006). Samples of Tsuga canadensis at the discharge points and at the control site indicate elevated chloride in plant tissues.ConclusionsDetermination of exceedances of chronic and acute standards vary based on the sampling location and medium, indicating a need for consistency and outcome-based monitoring point selection criteria and a move away from reliance on self-reporting by permittees.

Soil erosion hazard map for river basin managers: An example for the water bodies of the Loire river basin (France)

Soil erosion on agricultural land is associated with deleterious off-site impacts including the siltation and the pollution of the receiving water bodies. To better manage this situation, local/regional water agencies need spatially-distributed information to compare the sensitivity to erosion of the areas draining into these water bodies and supplying the vast majority of sediment and associated pollutants leading to this water quality impairment. These soil erosion hazard maps are now often included in the latest versions of the basin management plans that must be designed to meet the water quality objectives of the EU Framework Directive. However, the resolution of these maps is often too coarse to meet the practical needs of these agencies. Accordingly, the current research used the latest input databases to improve the MESALES model outputs in one of the largest French River basins (Loire, 117,000 km2), with the implementation of three main modifications. First, the seasonal variations of land cover were incorporated into the model through a revised set of expert rules based on the agricultural census data. Second, the discrimination of the soil textures was improved within the infiltration and erodibility module of the model. Third, variations in rainfall erosivity across the study area were described taking into account the latest erosivity map available at the European scale. Then, the model results obtained with the updated model version were compared with those generated by the previous version. Overall, the simulated soil erosion hazard changed for 35% of the pixels of the Loire River basin, with a significant increase of the lowest hazard classes during all seasons except summer. When aggregating the results at the scale of water bodies, the simulated erosion hazard changed for 49% of these management units. Although 28% of these water bodies were associated with a lower hazard, 23% of the river systems were attributed a higher erosion risk. The implications of these model/map revisions for the local decision makers were discussed, taking the strategy of concentrating the management budget on those water bodies associated with the highest erosion risk as an example. In the future, this model could be used to compare the soil erosion hazard in contrasted regions of Europe and to simulate the impact of management plans designed to decrease this risk to support the decisions of water agencies.

In situ chelation of phosphorus using microencapsulated aluminum and iron sulfate to bind intestinal phosphorus in rainbow trout (Oncorhynchus mykiss)

Excess phosphorus (P) in freshwater ecosystems increases primary production which, left uncontrolled, may lead to eutrophication, accelerating the ageing process of receiving water bodies. To limit phosphorus release resulting from freshwater aquaculture, we propose to incorporate microencapsulated P-chelating agents into fish diets. In a first trial, alum (Al2SO4) and ferrous sulfate (FeSO4) were encapsulated by spray-chilling in a hydrogenated lipid matrix. Two practical diets incorporating one of these two chelating elements (6 g/kg) were fed to fish for five weeks (w), and P release from resulting feces was compared. In a second trial, a similar approach was used to evaluate the impact of increasing supplementation of encapsulated alum (3, 6, 15 g/kg of diet). Feces from the fish fed with the diets incorporating alum and ferrous sulfate released 62 % and 54 % respectively less P than feces from fish fed with control diets. The second experiment revealed a negative correlation between the level of encapsulated Al2SO4 included in the diet and phosphorus released by the feces (y = 0.18x2 ˗ 4.78x + 62.7; R2 = 0.93). Feces from feed incorporating Al2SO4 at 0, 3, 6 and 15 g/kg released 62 %, 52 %, 39 %, and 32 % of the total fecal P after 14 days respectively. Fish fed encapsulated Al2SO4 have similar growth performance and mineral status. Incorporation of encapsulated P-chelating agents into fish feed offers an opportunity to manage P release from fish feces. Long-term feeding studies are required for validation of dietary Al2SO4 and FeSO4 impacts on potential toxicity and growth/environmental performance following chronic feeding of encapulated P chelating agents.

What evidence exists related to soil retention of phosphorus from on-site wastewater treatment systems in boreal and temperate climate zones? A systematic map protocol

BackgroundSoil-based on-site wastewater treatment systems (OWSs) are suspected to contribute to eutrophication of surface waters, due to the discharge of phosphorus (P). However, along the flow path between the facilities and surface waters, different processes contribute to delay the transport of phosphorus through the ground. This may reduce the unwanted impact on receiving water bodies. However, the strength and significance of this so-called soil retention remains unclear.In Sweden, there are nearly one million OWSs. To protect surface waters, a high P removal rate (up to 90%) is often required by the local municipalities. However, since these requirements may have costly consequences to property owners, it is debated as to whether they are too strict. In this debate, it is often claimed that the retention of P occurring in natural environments may be underestimated by authorities. Accordingly, there is a need for a scrutiny of the available evidence related to soil retention of phosphorus from OWSs. This is the objective of the planned systematic map. Focus will be on boreal and temperate climate zones.MethodsSearches will be made for peer-reviewed articles and grey literature using bibliographic databases, search engines, specialist websites and stakeholder contacts. The references will be screened for relevance according to a predefined set of eligibility criteria. At stage one, after testing and clarifying the eligibility criteria, the references will be single-screened based on title and abstract. At stage two, potentially relevant references will be screened in full-text independently by two reviewers. We will compile a detailed database of the relevant studies. Moreover, a narrative report will be produced, describing the research landscape in general terms. This will be carried out with a conceptual model, describing the processes involved in P retention in natural environments, as a foundation. It will be discussed where the respective studies/study types fit into the conceptual model, and also evaluated how each study/study type can be related to the overarching question of eutrophication. Moreover, we will describe identified knowledge gaps that warrant further primary research effort, as well as identified knowledge clusters that could be suitable for systematic reviews.

Most relevant sources and emission pathways of pollution for selected pharmaceuticals in a catchment area based on substance flow analysis

The release of micropollutants in surface water depends on different sources and on different pathways. Through substance flow analysis, this study estimates the annual load of two pharmaceuticals (carbamazepine and sulfamethoxazole) in a catchment area, due to different emission pathways: wastewater treatment plant effluent, combined sewer overflows, and runoff from sludge and manure amended soil. It emerged that wastewater treatment plant effluent is the main emission pathway for carbamazepine (98.5% referring to the total released annual load) and land runoff (98%) for sulfamethoxazole.The study also investigates the parameters (including manure disposed on the land, removal efficiency and combined sewer overflow flowrate) which mostly influence the results, and those which are affected by higher uncertainty. The most uncertain parameters are those determining the fate of pharmaceuticals once in soil and surface water.The study concludes with a comparison between the predicted concentrations in different points of the receiving water body of the two key compounds, modeled with substance flow analysis, and those directly measured in a dedicated sampling campaign. The main discrepancies were found for sulfamethoxazole. Future research focusing on monitoring campaigns under different weather conditions and in different environmental compartments (soil and water) will certainly provide new insights in this kind of study.

Characterization of Antibiotic Resistance and Metal Homeostasis Genes in Midwest USA Agricultural Sediments

Microbial antibiotic resistance is a naturally occurring phenomenon that has grown in part with the use of antibiotics in agricultural operation. There are also known connections between genes for metal homeostasis and antibiotic resistance, and either antibiotics or metals may select for both kinds of genes. Antibiotics, metals, and their associated genes have the potential to enter agricultural drainage channels and migrate to downstream locations through receiving water bodies. A relatively new agricultural best management practice—the two-stage channel design—functions by sequestering sediments and dissolved constituents as they flow through agricultural ditches from surface runoff and tile drainage discharge. Sedimentation in agricultural watersheds may entrap aggregate pollutants including antibiotics, metals, and associated resistance genes before transport into the drainage system. Here, we characterized the abundance and diversity of 22 antibiotic resistance and metal homeostasis genes in three two-stage channels that had self-developed in an area dominated by agricultural land use. Additionally, we analyzed the sediments for 17 antibiotics and nine metals that could affect the selection of these genes. In these rural systems that drain into Lake Erie, the abundance of antibiotic resistance and metal homeostasis genes were on the lower end of ranges (e.g., <106 gene copies g−1 of intI1) reported in other riverine and lake systems, with only five genes—intI1, aacA, mexB, cadA, and merA—differing significantly between sites. The diversity of antibiotic resistance and metal homeostasis genes for these sediment samples were largely similar to other human impacted environments. Few antibiotics were detected in two stage channel sediments, with concentrations below the quantifiable limits (<0.02–34.5 µg kg−1 soil) in most cases. Likewise, metals were present at what could be considered background concentrations. Despite serving as important drainage channel features in a region dominated by agricultural land use, results serve as an important baseline reference against which other monitoring studies can be compared to assess the perturbation of antibiotics and metals on agricultural channel sediments.

Modelling the impact of runoff generation on agricultural and urban phosphorus loading of the subtropical Poyang Lake (China)

Water quality degradation and eutrophication in surface water bodies caused by excessive phosphorus loads from agriculture and urbanisation are widespread problems. Although phosphorus (P) is often the limiting factor of aquatic ecosystems, only few studies have characterised the primary factors that influence P export in subtropical monsoon catchments. This study aims to assess the temporal and spatial variations in P fluxes, and to investigate the factors controlling P export in a subtropical catchment. Runoff and P export in the Le An River catchment, which flow to Poyang Lake (China) were evaluated using the HYPE model. Sensitivity analysis and calibration of hydrological and P transport parameters were undertaken using PEST. Results show that: (a) HYPE reproduced sufficiently well (NSE ≥ 0.73, |PBIAS| ≤ 14.5%) the stream flow dynamics for widely varying climatic conditions and across six sub-catchments of contrasting physiographic characteristics; (b) HYPE captured intra-annual patterns of total P (TP) loads, although with overestimation of annual TP loads by 8.5–47.0% across two monitoring sites; (c) TP loads had the ranges between 0.24 and 0.88 kg/ha/yr and 4.31–4.69 kg/ha/yr from forest-dominant upstream areas and the downstream plains region, respectively, with the latter being more urbanised and having higher percentage of agriculture; (d) Soil erosion from surface runoff and adsorption/desorption of soil P are the main factors controlled P export from the catchment; (e) most P export occurred during March-August when rainfall-runoff is highest and agricultural practices are most active; (f) stream TP concentrations were greatly affected by point source inputs, especially during low-flow conditions in downstream plains region. This study indicates that measures to reduce TP export to receiving water bodies in subtropical monsoon areas, like Poyang Lake, should focus on managing diffuse sources from soil erosion and surface runoff etc., whereas improvements to sewage management is more likely to reduce river TP concentrations during low-flow periods.

Assessment of multiclass pharmaceutical active compounds (PhACs) in hospital WWTP influent and effluent samples by UHPLC-Orbitrap MS: Temporal variation, removals and environmental risk assessment

Nowadays the occurrence and associated risks of Pharmaceutical Active Compounds (PhACs) in the aquatic environment comprises a major issue. In the present study, a comprehensive survey on contamination profiles, occurrence, removals, temporal variation and ecological risk of multiclass multiresidue PhACs, such as antibiotics, non-steroidal anti-inflammatories, lipid regulators and phsychiatrics, (including past and newly monitored PhACs as well as some of their metabolites) was performed in wastewaters from the WWTP of Ioannina University hospital along one year period on a monthly sampling basis. WWTP influent and effluent samples were analyzed for physicochemical quality parameters and PhACs concentration levels using Ultra High Performance Liquid Chromatography-Orbitrap-Mass Spectrometry (UHPLC-Orbitrap-MS), after Solid Phase Extraction (SPE) through Oasis HLB cartridges. Influent concentrations ranged between < LOQ (Limit of Quantification) for diclofenac and tolfenamic acid and 48586 ng/L for caffeine, while effluent concentrations between < LOQ for tolfenamic acid and simvastatin and 3361 ng/L for caffeine. Removal efficiencies ranged between −132.6% for venlafaxine and 100% for caffeine. Environmental risk assessment by means of Risk Quotient (RQ) for maximum and minimum concentration levels as well as optimized by the frequency of exceeding toxicity threshold values, RQf, was applied revealing that up to 12 PhACs posed acute toxicity (clofibric acid, fenofibrate, sulfadiazine, sulfamethoxazole, trimethoprim, amitryptiline, fluoxetine, fluvoxamine, norfluoxetine, sertraline, venlafaxine, caffeine) while up to 4 compounds exerted long-term toxicity (sulfamethoxazole, fluoxetine, sertraline, caffeine) at least for one of the studied organisms. Furthermore, mixture RQMEC/PNEC and RQSTU effect of multiple compounds showed high potential risks of the target groups in some cases, although some contaminants were not included due to lack of available data. Results can be used to prioritization of PhACs and their metabolites for surveillance in receiving water bodies as well as development of knowledge on toxicity and mechanism(s) of action.

Characterization of leachate produced by a landfill and its influence on a sewage treatment plant

AbstractAlthough landfills are generally an environmentally safe option for the disposal of solid waste, the treatment and management of landfill leachate are still critical. The aim of this work was to study through physical‐chemical analyses the effects of leachate on the effluent of the sewage treatment plant to which it is disposed on both study sites. The results were compared with those of existing studies, current legislation, municipal waste management practices, and landfill operations. Ethinylestradiol analyses were also performed on the influent and effluent from the sewage treatment plant. The results showed that the landfill leachate has a polluting potential, being found parameters above the allowed value, such as chemical oxygen demand (3,510.33 mg L−1), chloride (3,631.78 mg L−1), and manganese (21.61 mg L−1). The properties of the leachate indicated that the landfill was still in the acid formation phase and did not influence the influent that reached the sewage treatment plant in any way. Ultimately, the quality of the discharged wastewater met all of the predischarge regulatory criteria for materials being sent to a receiving water body, except for the chloride parameter that is not being treated at all.

Occurrence of Fluoroquinolones and Sulfonamides Resistance Genes in Wastewater and Sludge at Different Stages of Wastewater Treatment: A Preliminary Case Study

This study identified differences in the prevalence of antibiotic resistance genes (ARGs) between wastewater treatment plants (WWTPs) processing different proportions of hospital and municipal wastewater as well as various types of industrial wastewater. The influence of treated effluents discharged from WWTPs on the receiving water bodies (rivers) was examined. Genomic DNA was isolated from environmental samples (river water, wastewater and sewage sludge). The presence of genes encoding resistance to sulfonamides (sul1, sul2) and fluoroquinolones (qepA, aac(6′)-Ib-cr) was determined by standard polymerase chain reaction (PCR). The effect of the sampling season (summer – June, fall – November) was analyzed. Treated wastewater and sewage sludge were significant reservoirs of antibiotic resistance and contained all of the examined ARGs. All wastewater samples contained sul1 and aac(6′)-lb-cr genes, while the qepA and sul2 genes occurred less frequently. These observations suggest that the prevalence of ARGs is determined by the type of processed wastewater. The Warmia and Mazury WWTP was characterized by higher levels of the sul2 gene, which could be attributed to the fact that this WWTP processes agricultural sewage containing animal waste. However, hospital wastewater appears to be the main source of the sul1 gene. The results of this study indicate that WWTPs are significant sources of ARGs, contributing to the spread of antibiotic resistance in rivers receiving processed wastewater.

Electrocoagulation for nutrients removal in the slaughterhouse wastewater: comparison between iron and aluminum electrodes treatment

ABSTRACT The poultry slaughterhouse wastewater has a high pollutant load, mainly organic matter, and nutrient content. The nitrogen and phosphorus discharge can cause eutrophication of the receiving water bodies. Electrocoagulation has been studied for several pollutants removal from different sources. The objective of this work was to evaluate the electrocoagulation process in the poultry slaughterhouse wastewater treatment using both iron and electrodes to remove total nitrogen and phosphorus. After the raw and polished wastewater characterisation, a 2³ Central Composite Rotatable Design was applied to evaluate the current density, initial pH, and electrocoagulation time influence on the nutrients removal and to find the optimum condition of nutrients removal. Once the optimum condition for nutrient removal was stablished, other physicochemical, microbiological, and ecotoxicological parameters, as well as the treatment cost, were investigated to determine which electrode material was the most efficient. For raw wastewater, applying the optimum treatment condition of 20 mA cm−2 current density, initial pH 6.2, and time of 20 min, the nitrogen and phosphorus removal presented similar for both electrode materials. Besides being cheaper ($ 4.13 m−3), iron electrode treatment presented better Chemical Oxygen Demand, oils and greases, solids, and ecotoxicity removal. For polished wastewater, the treatment with aluminum electrode was more efficient under the applied current density of 30 mA cm−2, initial pH 8 and time of 10 min, obtaining the lowest cost $ 3.89 m−3. In the iron electrode case, the final pH exceeds the limits established by local legislation requiring correction for release into water bodies.

Plant-based diets add to the wastewater phosphorus burden

Global food production and current reliance on meat-based diets requires a large share of natural resource use and causes widespread environmental pollution including phosphorus (P). Transitions to less animal-intensive diets address a suite of sustainability goals, but their impact on society’s wastewater P burden is unclear. Using the UK as our example, we explored historical diet changes between 1942 and 2016, and how shifting towards plant-based diets might impact the P burden entering wastewater treatment works (WWTW), and subsequent effluent P discharge to receiving water bodies. Average daily per capita P intake declined from its peak in 1963 (1599 mg P pp−1 d−1) to 1354 mg P pp−1 d−1 in 2016. Since 1942, the contribution of processed foods to total P consumption has increased from 21% to 52% in 2016, but consumption of total animal products has not changed significantly. Scenario analysis indicated that if individuals adopted a vegan diet or a low-meat (‘EAT- Lancet’) diet by 2050, the P burden entering WWTW increased by 17% and 35%, respectively relative to baseline conditions in 2050. A much lower P burden increase (6%) was obtained with a flexitarian diet. An increasing burden of P to WWTW threatens greater non-compliance with regulatory targets for P discharge to water, but also presents an opportunity to the wastewater industry to recycle P in the food chain, and reduce reliance on finite phosphate rock resources. Sustainable diets that reduce food system P demand pre-consumption could also provide a source of renewable fertilizers through enhanced P recovery post-consumption and should be further explored.

Should TBT continue to be considered an issue in dredging port areas? A brief review of the global evidence

Dredging is periodically required to keep channels and maneuvering basins open in many ports around the world. However, the dredging of contaminated sediments may turn this routine procedure into a source of pollution in the receiving water bodies. Many pollutants, such as heavy metals, organic or organometallic compounds are present in high concentrations due to human activities in the coastal areas, where ports are located. Thus, the risks posed by dredging should be carefully evaluated for the conservation of environmental quality. Organotin compounds were extensively used as antifouling biocides worldwide for decades, causing considerable damage to localized coastal areas before being banned by IMO in 2008. Afterward, organotin concentrations decreased in most studied areas, as indicated by several recent studies in the literature. In some instances, however, there are still instances of biological effects of organotins application or legacy pollution being reported. It could be argued that until a complete recovery could be inferred, these “hot spots” should have organotins included in the evaluation of possible environmental impacts of dredging activities. Besides, when considering naval activities, most currently used antifouling systems still included biocides. The possible risks posed by these alternative technologies should be evaluated in the same way. This article briefly reviews this argument, using the recent literature on this subject.

Using water footprint concepts for water security assessment of a basin under anthropogenic pressures

The evaluation of water shortages and pollution levels is crucial for watershed management and sustainable development. This paper proposes a water footprint (WF) sustainability assessment approach to analyse water security in a river basin under human pressures. The methodology involves a comprehensive assessment of the current water security at different spatial and temporal levels, and identifies suitable response formulations to achieve sustainability. Field surveys and measurements (streamflow, water quality) were carried out, and the Soil and Water Assessment Tool model was used for assessing water balance components and water quality. The study was carried out in the Canale d'Aiedda river basin (Taranto, Italy), which is part of the ‘area of environmental crisis’ of Taranto, which requires remediation of surface water, groundwater, soil and subsoil. Considering all the anthropogenic activities in the basin, including agriculture and the treated effluent disposed of via wastewater treatment plants (WWTPs), the average WF was 213.9 Mm3 y−1, of which 37.2%, 9.2% and 53.6% comprised respectively for WFgreen, WFblue and WFgrey. The WF sustainability assessment revealed that pollution was the main factor affecting surface water security. In particular, point sources contributed with 90% to the total WFgrey, and lower pollutant thresholds should be fixed for effluent from WWTPs in order to increase water quality of the receiving water body. In addition, for assuring water security the extension of the natural areas should be increased to support biodiversity in the river basin and soil management strategies should be improved to allow more water to be retained in the soil and to reduce nutrients in surface runoff. This study demonstrates that the WF sustainability assessment is a feasible approach for integrated water resources management, as well as offering a much broader perspective on how water security can be achieved in a Mediterranean basin affected by multiple anthropogenic stressors.

Global Dam‐Driven Changes to Riverine N:P:Si Ratios Delivered to the Coastal Ocean

AbstractRiver damming alters nutrient fluxes along the land‐ocean aquatic continuum as a result of biogeochemical processes in reservoirs. Both the changes in riverine nutrient fluxes and nutrient ratios impact ecosystem functioning of receiving water bodies. We utilize spatially distributed mechanistic models of nitrogen (N), phosphorus (P), and silicon (Si) cycling in reservoirs to quantify changes in nutrient stoichiometry of river discharge to coastal waters. The results demonstrate that the growing number of dams decouples the riverine fluxes of N, P, and Si. Worldwide, preferential removal of P over N in reservoirs increases N:P ratios delivered to the ocean, raising the potential for P limitation of coastal productivity. By midcentury, more than half of the rivers discharging to the coastal zone will experience a higher removal of reactive Si relative to reactive P and total N, in response to the rapid pace at which new hydroelectric dams are being built.

Comprehensive evaluation of stormwater pollutants characteristics, purification process and environmental impact after low impact development practices

Understanding the stormwater characteristics and purification process of different underlying surfaces in an intensive Low Impact Development (LID) catchment is critical for summarizing problems of built LID practices and providing references for future LID construction. This research program investigated stormwater pollutants from several sites in Yuelai, Chongqing, a pilot area of Chinese Sponge Cities. The results showed that different LID areas had different stormwater pollutant characteristics and purification processes due to different LID layouts and facilities. For highway runoff, pollutants event mean concentrations (EMCs) were mainly affected by rainfall characteristics rather than road slopes. Ammonia was the primary nitrogen pollutant, and it always has a heavier first flush effect (FFE). For the green parks, runoff volume and FFE reduction were effective because of the high density of soil-based LID facilities and natural green space. However, nitrate and organic matter leaching also existed. The commercial areas often have more engineering facilities which could remove solids pollutant and phosphorus effectively. However, nitrogen removal performance was poor. The residential areas compromised between green parks and commercial areas. Overall, LID construction significantly reduced pollutants EMCs, volume and FFE, ameliorated water quality of the receiving water bodies. Nevertheless, some problems, such as inadequate nitrogen removal and runoff scouring effect, still need to be resolved in the future.

Chromium Pollution in European Water, Sources, Health Risk, and Remediation Strategies: An Overview.

Chromium is a potentially toxic metal occurring in water and groundwater as a result of natural and anthropogenic sources. Microbial interaction with mafic and ultramafic rocks together with geogenic processes release Cr (VI) in natural environment by chromite oxidation. Moreover, Cr (VI) pollution is largely related to several Cr (VI) industrial applications in the field of energy production, manufacturing of metals and chemicals, and subsequent waste and wastewater management. Chromium discharge in European Union (EU) waters is subjected to nationwide recommendations, which vary depending on the type of industry and receiving water body. Once in water, chromium mainly occurs in two oxidation states Cr (III) and Cr (VI) and related ion forms depending on pH values, redox potential, and presence of natural reducing agents. Public concerns with chromium are primarily related to hexavalent compounds owing to their toxic effects on humans, animals, plants, and microorganisms. Risks for human health range from skin irritation to DNA damages and cancer development, depending on dose, exposure level, and duration. Remediation strategies commonly used for Cr (VI) removal include physico-chemical and biological methods. This work critically presents their advantages and disadvantages, suggesting a site-specific and accurate evaluation for choosing the best available recovering technology.

Alternative Deicers for Winter Road Maintenance—A Review

The use of roadway deicers, typically made of sand or salt, is essential for achieving safe roadway conditions by reducing ice and snow. Unfortunately, deicers can have detrimental effects on the surrounding infrastructure and environment. Traditional inorganic deicers, such as abrasives and chloride salts, have the most widespread usage, but recent concerns of the negative effects of chlorides on the environment have led to emerging alternative organic deicers. This paper provides a comprehensive review of the effectiveness and impacts of organic deicers including agro-based products, acetates, formates, glycols, and succinates. The benefits and negative impacts on the road, environment, and infrastructure are reviewed, as well as the performance of each deicer for snow and ice control on roadways. The environmental concerns of the organic deicers are discussed, including the largest environmental concern: the increase in biological oxygen demand (BOD) to receiving water bodies. The impact of deicers on metals and infrastructure is presented as it varies considerably for each alternative deicer. Finally, opportunities and challenges to implementing alternative deicers in the field is discussed.

Environmental Dissemination of Selected Antibiotics from Hospital Wastewater to the Aquatic Environment.

The environmental dissemination of selected antibiotics from hospital wastewater into municipal wastewater and lastly to a receiving water body was investigated. Selected antibiotics (azithromycin (AZM), ciprofloxacin (CIP), clindamycin (CDM), doxycycline (DXC) and sulfamethoxazole (SMZ)) present in effluents of academic hospital wastewater, influents, sewage sludge, and effluents of municipal wastewater, receiving water, and its benthic sediment samples were quantified using the Acquity® Waters Ultra-Performance Liquid Chromatography System hyphenated with a Waters Synapt G2 coupled to a quadrupole time-of-flight mass spectrometer. The overall results showed that all assessed antibiotics were found in all matrices. For solid matrices, river sediment samples had elevated concentrations with mean concentrations of 34,834, 35,623, 50,913, 55,263, and 41,781 ng/g for AZM, CIP, CDM, DXC, and SMZ, respectively, whereas for liquid samples, hospital wastewater and influent of wastewater had the highest concentrations. The lowest concentrations were observed in river water, with mean concentrations of 11, 97, 15, and 123 ng/L, except for CDM, which was 18 ng/L in the effluent of wastewater. The results showed that the highest percentages of antibiotics removed was SMZ with 90%, followed by DXC, AZM and CIP with a removal efficiency of 85%, 83%, and 83%, respectively. The antibiotic that showed the lowest removal percentage was CDM with 66%. However, the calculated environmental dissemination analysis through the use of mass load calculations revealed daily release of 15,486, 14,934, 1526, 922, and 680 mg/d for SMZ, CIP, AZM, DXC, and CDM, respectively, indicating a substantial release of selected antibiotics from wastewater to the river system, where they are possibly adsorbed in the river sediment. Further research into the efficient removal of antibiotics from wastewater and the identification of antibiotic sources in river sediment is needed.