Wastewater Effluent Discharge Research Articles

Application of assessment models for pollution and health risk from effluent discharge into a tropical stream: case study of Inyishi River, Southeastern Nigeria.

Pollution and health risk assessment models were used to study the effects of effluents discharged into the Inyishi River, Ikeduru LGA, Imo State, Nigeria. The study aims at investigating the environmental health effects of wastewater effluent discharge from the aluminum extrusion company on the Inyishi River. Samples were collected from both the aluminum extrusion company and Inyishi River and analyzed for physicochemical and trace metal parameters. Models adopted for assessment include transfer factor (TF), contamination factor (Cf), pollution load index (PLI), ecological risk factor (Er), water quality index (WQI), hazard quotient (HQ), and hazard index (HI). The results of the study revealed that pH and TH were within the Nigerian Standard for Drinking Water Quality (NSDWQ) and World Health Organization (WHO) standards. EC values at 2235 ± 0.001 and 105 ± 0.03 μS/cm for S3 and S4 respectively were higher than the permissible standards, while the values of EC at 24.04 ± 0.03, 5.26 ± 0.005, and 0.05 ± 0.01 μS/cm respectively for S1, S2, and SR are within the WHO standard. Very high concentration of SO42- was recorded at S3, while low concentration was measured at S2. Mean values of heavy metal ions studied were within NSDWQ and WHO standards for safe drinking water except for Al, Zn, Cd, Fe, and Mn, with the mean values of metal concentrations observed in the order Al > Fe > Zn > Mn > Cd > Cr. Positive linear correlation based on heavy metal contamination was observed for samples S1 and S2 with SR. High TF values were observed in decreasing order Mn > Cd > Cr > Fe > Zn. Similarly, very high CF was observed for Cd and Al while the PLI was generally high for all the samples. Low Er values were observed for all metals except for Cd, with the mean value of Er observed in the decreasing order Cd ˃ Mn ˃ Zn ˃ Cr. The river water sample generally revealed high WQI and was thus categorized as poor quality. HQ and HI values were below unity (< 1), but might pose health risk to children in cases of prolonged dermal adsorption. In conclusion, the quality of the Inyishi River has been negatively impacted by the wastewater effluent from the aluminum extrusion company. Proper treatment of the river water is therefore recommended before use for domestic purposes as prolonged usage of the untreated water might likely pose serious environmental health risks.

Regulation of Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonic Acid (PFOS) in Drinking Water: A Comprehensive Review

Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) are receiving global attention due to their persistence in the environment through wastewater effluent discharges and past improper industrial waste disposal. They are resistant to biological degradation and if present in wastewater are discharged into the environment. The US Environmental Protection Agency (USEPA) issued drinking water Health Advisories for PFOA and PFOS at 70 ng/L each and for the sum of the two. The need for an enforceable primary drinking water regulation under the Safe Drinking Water Act (SDWA) is currently being assessed. The USEPA faces stringent legal constraints and technical barriers to develop a primary drinking water regulation for PFOA and PFOS. This review synthesizes current knowledge providing a publicly available, comprehensive point of reference for researchers, water utilities, industry, and regulatory agencies to better understand and address cross-cutting issues associated with regulation of PFOA and PFOS contamination of drinking water.

Abundance and seasonal variability of aloricate ciliates and tintinnids in a eutrophic coastal lagoon system of the Gulf of California, Mexico

The heterotrophic ciliates, mainly composed of aloricate (naked) ciliates, are the dominant size fraction and play an important role in low impacted subtropical coastal systems of central region of the Gulf of California, México, by consuming up to 70% of phytoplankton biomass (pico- and nanoplankton). However, there is no information concerning microzooplankton populations for lagoons highly impacted by anthropogenic activities. This study established a baseline of regional abundance and spatio-temporal variability of aloricate ciliates and tintinnids, in the eutrophic lagoon system Topolobampo-Santa María-Ohuira. Their total abundance ranged from 10 to 56.1×103 org L−1 for ciliate, and 10 to 14.80×103 org L−1 for tintinnids. Aloricate ciliates mean abundances were approximately four times higher than that of tintinnids, with higher values occurring in winter–spring and punctuated by minor spurts during the rainy months. The study found that eutrophication levels (6.5 to 7.3 TRIX units) were the main factor contributing to their abundance, though tropic interactions and lagoon hydrological characteristics were also relevant. Their distribution revealed that substantial population increases resulted from nutrient enriched residual agricultural drainage at Santa María and Ohuira that exacerbated eutrophication conditions. Canonical correspondence analysis identified that lower values of salinity was due to the influence of wastewater effluent discharge and was the main variable that was related with tintinnids; while dissolved oxygen and chlorophyll-a, variables associated to large primary production, were related to ciliates. The deteriorated water quality of Santa María and Ouhira lagoons likely delineated the low macro-zooplanktonic biomasses and consequently the higher aloricate ciliates and tintinnids abundances.

Occurrence and Probable Sources of Urban-Use Insecticides in Marine Sediments off the Coast of Los Angeles.

Insecticides such as pyrethroids and fipronil are used in large amounts in both agricultural and urban settings and have the potential to elicit toxicity to nontarget aquatic organisms. In California, like in many other regions of the world, urban centers are located along the coast, and it is documented that urban-use insecticides enter the marine environment, where little is known about their occurrence and consequences. In this study, we measured the spatial distribution of pyrethroids and fipronil (and its metabolites) on the Palos Verdes Shelf off the coast of Los Angeles. Total pyrethroid levels ranged from nd to 170 μg/kg (dry weight), and fipronil sulfide levels ranged from 1.8 to 5.6 μg/kg. Two pyrethroids were traced to wastewater effluent discharge, while two others and fipronil sulfide were traced to to surface runoff. Toxicity units (TUs) were estimated for benthic invertebrates, which ranged from no toxicity (nt) to 146 for total pyrethroids, and 0.09 to 1.6 and 4.2 to 75 for fipronil sulfide, depending on the indicator species. Therefore, near-shore deposition of urban-use insecticides due to wastewater discharge and surface runoff poses a significant risk to marine benthic invertebrates and highlights the importance of monitoring near-shore ocean environments and developing mitigation strategies to reduce seaward movement.

Evaluation of the artificial sweetener sucralose as a sanitary wastewater tracer in Narragansett Bay, Rhode Island, USA

Narragansett Bay is an urban estuary that historically has been impacted by long-term discharge of sanitary wastewater (WW) effluents. High-density water sampling was conducted in Narragansett Bay, RI, USA, in an effort to understand the distribution and behavior of sucralose, an artificial sweetener that has shown utility as a sanitary wastewater tracer. Water samples were collected at sixty-seven sites and analyzed for sucralose, whose performance was compared to other tracers present in wastewater effluents. Concentrations of sucralose were much higher than the other tracers measured, carbamazepine and caffeine, ranging from 18 to 3180 ng/L and corresponded well with salinity (r2 = 0.88), demonstrating conservative behavior throughout the Bay. Mapped interpolation data using an empirical bayesian kriging model clearly show the spatial trends of WW and how estuarine processes influence dilution and dispersion throughout the Bay. These findings provide further evidence of the efficacy of sucralose as a wastewater tracer in large urban estuaries where continuous high-volume discharge of WW occur.

Modelling the effects of ferric salt dosing for chemical phosphorus removal on the settleability of activated sludge

There is a growing utilisation of ferric salts (Fe3+) for precipitation of phosphorus from wastewater due to tighter regulatory limits for wastewater effluent discharge. The effect of Fe3+dosing on activated sludge settleability indicators; zone settling velocity (ZSV) and stirred specific volume index (SSVI) were examined in laboratory-based batch settleability tests over a three years period. The experimental data revealed that ZSV increased with increasing dose of ferric salt as SSVI decreased with the highest changes obtained at a dose rate of 50 mgL-1. Fe3+ facilitated the agglomeration of the activated sludge flocs, thereby improving settleability. At >50 (mgL-1) of Fe3+, there was a slight breakdown in sludge settleability due mainly to surface charge reversals. The modelling of the settleability of ferric sludge in recent wastewater engineering practice for design and improvement purposes is presently based on conventional empirical sludge settleability models. This paper proposed a new activated sludge settleability model that describes the effects of Fe3+ dosing on the ZSV and SSVI of activated sludge. The exponential form of the Vesilind equation was optimised and validated to include ferric chemical dosing parameters. The proposed ferric settleability equations were found to effectively describe the settling characteristics of ferric sludge.

Dynamics of Wastewater Effluent Contributions in Streams and Impacts on Drinking Water Supply via Riverbank Filtration in Germany-A National Reconnaissance.

The discharge of wastewater effluents to a stream that is subsequently used for drinking water abstraction has been previously referred to as de facto water reuse. Where the abstraction of surface water for drinking water production occurs via induced bank filtration or aquifer recharge, additional site-specific factors should be considered to assess the impact of wastewater effluents on bank-filtered water. This study represents the first national reconnaissance to quantify wastewater effluent contributions in streams across Germany and consequences for indirect drinking water abstraction from these streams. An automated assessment using ArcGIS was conducted for river basins considering minimum and mean average discharge conditions of streams as well as discharge from more than 7500 wastewater facilities. In urban areas, where the natural base discharge is low, wastewater effluent contributions greater than 30-50% were determined under mean minimum discharge conditions, which commonly prevail from May to September. A conceptual model was proposed to estimate critical bank filtrate shares resulting in exceedances of monitoring trigger levels for health-relevant chemicals as a universal qualitative assessment regarding the relevance of de facto reuse conditions in surface waters used for drinking water abstraction. This approach was validated using chemical monitoring data for three case study locations.

Kinetics of Nutrient Removal in an Integrated Suspended Growth Reactor

Wastewater effluent discharge in a large amount of ammonia, nitrate and phosphorus lead to eutrophication the river. Eutrophication is a serious environmental issue that threaten the fishes and aquatic plants. To prevent this from happening, ammonia produced in STP and raw wastewater removal is achieved during nitrification by having an extended aeration while nitrate removal is achieved during denitrification in anoxic tank. In this research study, a pilot plant of integrated suspended growth system (i-SGS) reactor was used to achieve simultaneous removal of ammonia and nitrate. The reactor has three main compartments which are anoxic chamber, aeration camber, and clarifier and operated at a constant flow rate of 720 L/d and fixed SRT of 40 days. The RAS time was set to once every 10 minutes for 5 minutes while the IR time is once every 16 minutes for 5 minutes. The wastewater quality parameters, namely chemical oxygen demand (COD), ammonia, and nitrate were measured to determine and evaluate the removal efficiency of them in i-SGS whereas phosphorus was measured to ensure the effluent standard meet the C:N:P ratio requirement. Samples from four sampling points were taken to conduct the laboratory experiment and three replication of the results for each parameter were measured. It was determined that i-SGS was able to eliminate average 72% of COD at 46 mg/L of clarifier effluent, and achieved 95% of ammonia removal at average 1.22 mg/L of the clarifier effluent concentration while obtained 43% of nitrate removal in the anoxic tank. Last but not least, the C:N:P ratio obtained was 100:14:8, denoted that i-SGS has ample of nutrients loading provided because it is more than the minimum nutrient requirements, 100:5:1. The removal was possible through the nitrification-denitrification process in the i-SGS pilot plant bioreactor. The operational SRT of 40 days have shown to be effective and stable for the COD but not for nitrifiers. The effluent discharge of COD, ammonia and nitrate in the pilot plant i-SGS has meet the standard requirement of DOE Malaysia, standard A and B respectively.

Quantifying the effects of surface conveyance of treated wastewater effluent on groundwater, surface water, and nutrient dynamics in a large river floodplain

Restoration and reconnection of floodplain systems provide multiple societal and ecosystem benefits, while providing municipalities the opportunity to attempt alternative approaches to maintain infrastructure protection and function. In some restored floodplains, treated wastewater effluent discharge is redirected over land instead of directly into rivers to allow natural flow and infiltration, to facilitate restoration designs such as levee setback, and to provide additional freshwater to floodplain ecosystems. However, indirect discharge of treated effluent over land may pose risks to surface and groundwater when pollutants like excess nutrients enter the floodplain and undergo transformation. We investigated the consequences for groundwater and surface water quality when effluent was redirected as open water channels over a floodplain surface. In this study, seasonal floodplain nutrient concentrations in groundwater and surface water were observed for more than 5 years as a floodplain and wastewater treatment plant underwent a major restoration project that included river-floodplain reconnection with levee setback and redirection of effluent discharge from a river channel to open flow across the restored floodplain. Nutrient loading to the surrounding floodplain groundwater and surface water was observed, but based on measures of hydrological connectivity, groundwater flow paths, and biogeochemistry, nutrients from the effluent moved within the floodplain with minimal effect to the surrounding floodplain water quality. We did not find evidence of substantial additional processing that could replace advanced nutrient treatment in this system, however we did observe evidence of diverse nutrient processes that may support enhanced retention if treatment channels were designed to enhance these processes. We suggest that indirect discharge of high quality treated effluent in a restored floodplain is a viable alternative to direct discharge into a river when groundwater flow directs that discharge to habitats where minimal nutrient sensitivity is expected.

Positive responses of benthic macroinvertebrates to spatial and temporal reductions in water pollution downstream from a trout farm outlet

Inland trout farms can cause important adverse effects on freshwater communities due to the discharge of wastewater effluents into recipient rivers. In this research, responses of benthic macroinvertebrates to diminished water pollution downstream from a trout farm outlet were examined at spatial and temporal scales. Field studies were carried out in the Upper Tajuña River (Central Spain) during the springs of 2007 and 2015. Water pollution decreased, with increasing the downstream distance from the trout farm effluent, and also from 2007 to 2015 as a likely consequence of the lowered annual production of farmed rainbow trout following the 2008 economic recession. Reductions in water pollution resulted in increased concentrations of dissolved oxygen and decreased levels of turbidity and inorganic nutrients (ammonia and phosphate). Benthic macroinvertebrates responded positively to diminished water pollution by decreasing the relative abundance of collector-gatherers (oligochaetes and chironomids) and increasing the relative abundance of shredders and scrapers (ephemeropterans, plecopterans and trichopterans). In addition, values of taxonomic diversity and Biological Monitoring Water Quality biotic indices tended to increase. It is concluded that the wastewater treatment system of the trout farm should be improved to minimize the environmental impact on the recipient river.

Influence of Diltiazem on Fathead Minnows Across Dissolved Oxygen Gradients.

Water resources in many arid to semi-arid regions are stressed by population growth and drought. Growing populations and climatic changes are influencing contaminant and water chemistry dynamics in urban inland waters, where flows can be dominated by, or even dependent on, wastewater effluent discharge. In these watersheds, interacting stressors such as dissolved oxygen and environmental contaminants (e.g., pharmaceuticals) have the potential to affect fish physiology and populations. Recent field observations from our group identified the calcium channel blocker (CCB) diltiazem in fish plasma exceeding human therapeutic doses (e.g., Cmin ) in aquatic systems impaired because of nonattainment of dissolved oxygen water quality standards. Therefore our study objectives examined: 1) standard acute and chronic effects of dissolved oxygen and diltiazem to fish, 2) influences of dissolved oxygen at criteria levels deemed protective of aquatic life on diltiazem toxicity to fish, and 3) whether sublethal effects occur at diltiazem water concentrations predicted to cause a human therapeutic level (therapeutic hazard value [THV]) in fish plasma. Dissolved oxygen × diltiazem co-exposures significantly decreased survival at typical stream, lake, and reservoir water quality standards of 5.0 and 3.0 mg dissolved oxygen/L. Dissolved oxygen and diltiazem growth effects were observed at 2 times and 10 times lower than median lethal concentration (LC50) values (1.7 and 28.2 mg/L, respectively). Larval fathead minnow (Pimephales promelas) swimming behavior following low dissolved oxygen and diltiazem exposure generally decreased and was significantly reduced in light-to-dark bursting distance traveled, number of movements, and duration at concentrations as low as the THV. Individual and population level consequences of such responses are not yet understood, particularly in older organisms or other species; however, these findings suggest that assessments with pharmaceuticals and other cardioactive contaminants may underestimate adverse outcomes in fish across dissolved oxygen levels considered protective of aquatic life. Environ Toxicol Chem 2018;37:2835-2850. © 2018 SETAC.

Transcriptomic analysis of short-term 17α-ethynylestradiol exposure in two Californian sentinel fish species sardine (Sardinops sagax) and mackerel (Scomber japonicus)

Endocrine disrupting chemicals (EDCs) are substances which disrupt normal functioning of the endocrine system by interfering with hormone regulated physiological pathways. Aquatic environments provide the ultimate reservoir for many EDCs as they enter rivers and the ocean via effluent discharges and accumulate in sediments. One EDC widely dispersed in municipal wastewater effluent discharges is 17α-ethynylestradiol (EE2), which is one of the most widely prescribed medicines. EE2 is a bio-active estrogen employed in the majority of oral contraceptive pill formulations. As evidence of the health risks posed by EDCs mount, there is an urgent need to improve diagnostic tools for monitoring the effects of pollutants. As the cost of high throughput sequencing (HTS) diminishes, transcriptional profiling of an organism in response to EDC perturbation presents a cost-effective way of screening a wide range of endocrine responses. Coastal pelagic filter feeding fish species analyzed using HTS provide an excellent tool for EDC risk assessment in the marine environment. Unfortunately, there are limited genome sequence data and annotation for many of these species including Pacific sardine (Sardinops sagax) and chub mackerel (Scomber japonicus), which limits the utility of molecular tools such as HTS to interrogate the effects of endocrine disruption. In this study, we carried out RNA sequencing (RNAseq) of liver RNA harvested from wild sardine and mackerel exposed for 5 h under laboratory conditions to a concentration of 12.5 pM EE2 in the tank water. We developed an analytical framework for transcriptomic analyses of species with limited genomic information. EE2 exposure altered expression patterns of key genes involved in important metabolic and physiological processes. The systems approach presented here provides a powerful tool for obtaining a comprehensive picture of endocrine disruption in aquatic organisms.

Ligninolytic enzymes: Versatile biocatalysts for the elimination of endocrine-disrupting chemicals in wastewater.

Direct municipal wastewater effluent discharge from treatment plants has been identified as the major source of endocrine‐disrupting chemicals (EDC) in freshwaters. Consequently, efficient elimination of EDC in wastewater is significant to good water quality. However, conventional wastewater treatment approaches have been deficient in the complete removal of these contaminants. Hence, the exploration of new and more efficient methods for elimination of EDC in wastewater is imperative. Enzymatic treatment approach has been suggested as a suitable option. Nonetheless, ligninolytic enzymes seem to be the most promising group of enzymes for EDC elimination, perhaps, owing to their unique catalytic properties and characteristic high redox potentials for oxidation of a wide spectrum of organic compounds. Therefore, this paper discusses the potential of some ligninolytic enzymes (laccase, manganese peroxidase, and versatile peroxidase) in the elimination of EDC in wastewater and proposes a new scheme of wastewater treatment process for EDC removal.

A critical review of the occurrence of perfluoroalkyl acids in aqueous environments and their removal by adsorption onto carbon nanotubes

The presence of perfluoroalkyl acids (PFAAs) in aquatic environments is a cause of concern, due to their toxicity, possible ecological impact and adverse effects in man. The release of these pollutants into receiving water bodies occurs primarily through the discharge of untreated wastewater and industrial effluents. Consequently, there is a need to remediate wastewater containing these compounds before its discharge. In this review, the occurrence of PFAAs in water streams is reviewed, with the aim of providing in-depth information on the harmful effects arising through exposure to these pollutants by both man and the environment. One viable strategy for the removal of PFAAs from wastewaters is adsorption. This technique is discussed in relation to a number of conventional adsorbents and they are compared with the behaviour of a more effective adsorbent, namely, carbon nanotubes (CNTs). In particular, various functionalization strategies can increase the efficiency of CNTs for the removal of PFAAs. Sorption of PFAAs onto CNTs demonstrates good removal efficiencies and equilibrium is attained faster than with conventional adsorbents. This is attributed to the inherent properties of CNTs, such as large surface area/porosity, and the ease with which new functional groups are introduced onto the walls of the tubes. The adsorption mechanism of PFAAs is primarily enhanced through electrostatic interactions; however, other intermolecular forces, such as hydrogen bonding, hydrophobic interactions and ion-exchange, also play a role. This review aims at providing information on the occurrence and fate of PFAAs and the interactions involved in their removal from aqueous solutions by CNTs.

Nylon electrospun nanofibre water filtration media for wastewater treatment

Uncontrolled discharge of wastewater effluent has been a major concern due to the negative impact to human health and the environment. Increasingly stringent regulation has caused filter manufacturers to explore new materials to improve their products. Water filtration media using ultrafine fibres could be one of the potential solutions due to their promising characteristics. In this study, nanofibre incorporated water filtration media were produced, investigated, and characterized. A thin nylon electrospun nanofibre layer were deposited onto standard glass fibre filters and samples were collected at different electrospinning times. Suspended solid retention test was conducted using a vacuum filtration system based on BS EN 872:2005 standard. The absorbance of the feed and filtrate in terms of suspended solid and chemical oxygen demand of the water samples were also measured using a colorimeter based on Hach Method 8006 and 8000 respectively. The morphology of the filters was studied using scanning electron microscopy whilst porosity of the filtration media was inspected using mercury porosimetry. The results showed that the suspended solid and chemical oxygen demand removal capabilities of the filtration media improved significantly with the inclusion of nanofibre layer. A positive correlation was found between the performance of the filter and the amount of deposited nanofibre. It was also found that the inclusion of thin nanofibre layer had minimal effect to the overall porosity of the standard filters. Findings from this study provide a useful insight into the use of nanofibres in water filtration applications.

Differential Sensitivity of Wetland-Derived Nitrogen Cycling Microorganisms to Copper Nanoparticles

Metallic nanoparticles (NPs), the most abundant nanomaterials in consumer and industrial products, are the most probable class to enter the environment. In this study, wetland-derived microcosms were incubated with copper nanoparticles (Cu-NP) and ionic CuCl2 to investigate acute (10 days) and chronic (100 days) exposure towards nitrogen cycling microorganisms. The microbial ecology of wetlands play a crucial role in balancing nitrogen in pristine environments as well as in areas impacted by high nutrient loads (e.g., at wastewater effluent discharges). Gene abundance and expression changes were monitored using the GeoChip 5.0 high throughput functional gene microarray and metatranscriptomic shotgun sequencing (RNA-seq), respectively. After 10 days, the Cu-NP impacted microbial communities experienced structural shifts within microorganisms associated with dissimilatory nitrogen reduction accompanied by lower nitrate removal as compared to the unexposed controls. By day 100, these differences were largely resolved and nitrate removal was similar to the unexposed control. Furthermore, the Cu-NP exposed microcosms tolerated copper and were more resilient and adaptive than the unexposed controls based on the abundance and expression of other functions, including electron transfer, metal homeostasis, and stress response. These findings suggest sudden influxes of Cu-NPs into wetland systems may impair nitrogen removal initially, but long-term microbial shifts and functional redundancy would promote the net flux of total nitrogen out of the wetlands.

Evaluation of psychiatric hospital wastewater toxicity: what is its impact on aquatic organisms?

The primary source of pharmaceuticals to the aquatic environment is the discharge of wastewater effluents. Pharmaceuticals are a large and diverse group of compounds. Among them, psychotropic substances are particularly interesting to study due to their specific known mode of action. The present study was performed to investigate the effects of wastewater effluents from a psychiatric hospital wastewater treatment plant (WWTP) on several aquatic organisms. All the analyzed pharmaceuticals (10 compounds) were detected in WWTP effluents as well as in the receiving river. Although the environmental concentrations were generally at trace levels (ngL-1 to μgL-1), induce toxic effects were observed. This study showed the effects of the WWTP effluents on the oogenesis and/or embryogenesis of amphipod crustacean Gammarus fossarum, Japanese fish medaka Oryzias latipes, mollusk Radix peregra, and planarian Schmidtea polychroa. A decrease of the number of oocytes and produced embryos was observed for G. fossarum and S. polychroa. Similarly, the hatching rate of R. peregra was affected by effluents. In the receiving river, the macroinvertebrate community was affected by the wastewater effluents discharge.

DOMESTIC WASTEWATER IN INDONESIA: CHALLENGE IN THE FUTURE RELATED TO NITROGEN CONTENT

The option of reusing treated wastewater is becoming necessary for environment sustainability approach. In fact, wastewater effluent discharge regulations have become stricter leading to a better water quality. Municipal activities, agriculture, and rapid urbanization led to increased nitrogen and phosphorus discharge to the water system. More often, the effluents from municipal wastewater treatment plant failed to meet the national standard for effluent quality. Excess nutrients, mostly N and P is the main cause of eutrophication the which results in oxygen depletion, biodiversity reduction, fish kills, odor, and increased toxicity. Biological nutrient removal technologies are preferred and widely used to remove nitrogen and phosphorus from domestic wastewater and protect water quality. Chemical compositions in wastewater are highly diverse substances from simple compounds to complex polymers. Some wastewater samples were analyzed in this research. Conventional technology still retains the basic principle of complete nitrogen cycle through nitrification and denitrification. Anammox is a sustainable and cost-effective alternative to the basic method of nitrogen removal. Anammox has been identified as a new biotechnology for nitrogen reduction from wastewater. Compared to the common process of nitrogen removal, anammox can reduce 64% offaeration, 100% of an exogenous electron donor, and sludge production by 80-90%. Some benefits from anammox include high nitrogen removal rate, lower operational cost, and small space requirements. Anaerobic baffled reactor (ABR) in Indonesia has been used commonly as communal wastewater treatment. Promoting anammox process in ABR potentially become an improvement for ABR in removing nitrogen better. This combination process still outlined for further research.

Processes of distribution of pharmaceuticals in surface freshwaters: implications for risk assessment

The global consumption and production of pharmaceuticals is increasing concomitantly with concern regarding their environmental fate and effects. Active pharmaceutical ingredients are mainly released into the aquatic environment through wastewater effluent discharge. Once in the environment, pharmaceuticals can undergo processes of natural attenuation, i.e. dilution, sorption, transformation, depending on physico-chemical properties of the compound, such as water solubility, lipophilicity, vapour pressure, and environmental conditions, such as pH, temperature and ionic strength. A major natural attenuation process is the sorption on dissolved organic matter, colloids, suspended solids and sediments, which in turn control pharmaceuticals distribution, residence time and persistence in aquatic systems. Here we review studies of sorption capacity of natural sorbents to pharmaceuticals. These report on the importance of several environmental and sorbent-specific properties, such as the composition, quality, and amount of the sorbent, and the environmental pH, which determines the speciation of both the sorbent and compound. The importance of accounting for distribution processes on freshwater sorbents for any determination of environmental concentrations of pharmaceuticals is apparent, while the reliability of surrogate standards for measuring dissolved organic matter (DOM) distribution is evaluated in the context of the need for robust environmental risk assessment protocols.

Bioactive contaminants of emerging concern in National Park waters of the northern Colorado Plateau, USA

Pharmaceuticals and personal care products (PPCPs), wastewater indicators (WWIs), and pesticides (herein, Contaminants of Emerging Concern [CECs]) have been documented in surface waters throughout the world and have associated risks to aquatic life. While much research has focused on temperate and urbanized watersheds, less is known about CEC presence in semi-arid landscapes, where water availability is limited and populations are low. CEC presence in water and sediment is reported for 21 sites in eight U.S. national parks in the northern Colorado Plateau region. From 2012 to 2016, at least one PPCP and/or WWI was detected at most sites on over half of sampling visits, indicating that CECs are not uncommon even in isolated areas. CEC detections were generally fewer and at lower concentrations than in urbanized or agricultural watersheds. Consistent with studies from other U.S. regions, the most frequently detected CECs in this study include DEET, caffeine, organophosphorus flame retardants, and bisphenol A in water and fecal indicators and polycyclic aromatic hydrocarbons in sediment. Maximum concentrations in this study were generally below available water quality benchmarks, sediment quality guidelines, and risk assessment thresholds associated with vertebrates. Additional work is needed to assess the potential activity of hormones, which had high reporting limits in our study, and potential bioactivity of environmental concentrations for invertebrates, microbial communities, and algae. Potential sources of CEC contamination include upstream wastewater effluent discharges and National Park Service invasive-plant-control herbicide applications. CEC occurrence patterns and similarities between continuous and isolated flow locations suggest that direct contamination from individual visitors may also occur. While our data indicate there is little aquatic health risk associated with CECs at our sites, our results demonstrate the ubiquity of CECs on the landscape and a continued need for public outreach concerning resource-use ethics and the potential effects of upstream development.