The black soldier fly larvae (BSFL) have been widely extolled for the application in managing various solid organic wastes. Owing to the saprophagous nature of BSFL, a rapid valorization of solid organic wastes can be accomplished with the simultaneous production of valuable biochemical compounds derived from larval biomass. In the present works, the mixed waste coconut endosperm (w-CE) and soybean curd residue (SC-r) substrates with increasing protein nutritional constituent were administered to BSFL. The correlations between protein from larval feed substrates and nutritional profiles of BSFL biomasses were ultimately unveiled. The protein from larval feed substrates could be increased by increasing of SC-r portion against w-CE. At the w-CE:SC-r ratio of 3:2, the highest larval total weight gained and growth rate were attained; indicating an optimum protein nutritional constituent in mixed organics (12.4%) that could enhance the BSFL palatability. Further increment of protein nutritional constituent in mixed organics was found acidifying the residual larval feed substrate progressively, undermining the growth of BSFL. By feeding the BSFL with optimum mixed organics, the maximum accumulations of larval lipid and protein could be achieved. Transesterification of extracted lipid had demonstrated high in monounsaturated fatty acids (73%) which was suitable for biodiesel. The BSFL palatability was finally confirmed from the bioconversion viewpoint of mixed organic wastes. Again, achieving the highest bioconversion efficiency of 14% into larval biomass after accounting the metabolic loss of 54%. Therefore, a total of 68% of mixed w-CE and SC-r could be successfully bioconverted.
Suitable extraction technique and the least cost while reducing the environmental impact is the primary concern in timber transportation planning in undulate topography. Two types of extraction machines with unique characteristics to be applied in timber harvest area in Malaysia is combined for timber harvesting with the aim each machine will extract timber suitable to their ability. A Bees Algorithm (BA) was proposed to find an optimum TTP for timber extraction, forest road, and landing locations with grid cell-sized 10 m × 10 m and attributed with fixed and variable costs. The result shows the log fisher (1351 timbers) as a preferable extraction technique with total cost of RM 86,551.73 than the crawler tractor (206 timbers); the timber extraction route is 2630 m for the log fisher and 9860 m for the crawler tractor with total cost of RM 10,453.03. The model finds a suitable timber extraction technique and estimates the extraction costs. Further studies are required to compare the BA with other optimization methods for better results.
This study investigated the optimum conditions for total petroleum hydrocarbon (TPH) removal from diesel-contaminated water using phytoremediation treatment with Scirpus grossus. In addition, TPH removal from sand was adopted as a second response. The optimum conditions for maximum TPH removal were determined through a Box-Behnken Design. Three operational variables, i.e. diesel concentration (0.1, 0.175, 0.25% Vdiesel/Vwater), aeration rate (0, 1 and 2 L/min) and retention time (14, 43 and 72 days), were investigated by setting TPH removal and diesel concentration as the maximum, retention time within the given range, and aeration rate as the minimum. The optimum conditions were found to be a diesel concentration of 0.25% (Vdiesel/Vwater), a retention time of 63 days and no aeration with an estimated maximum TPH removal from water and sand of 76.3 and 56.5%, respectively. From a validation test of the optimum conditions, it was found that the maximum TPH removal from contaminated water and sand was 72.5 and 59%, respectively, which was a 5 and 4.4% deviation from the values given by the Box-Behnken Design, providing evidence that S. grossus is a Malaysian native plant that can be used to remediate wastewater containing hydrocarbons.
This paper reports on the optimization of palm oil mill effluent (POME) degradation in a UV-activated-ZnO system based on central composite design (CCD) in response surface methodology (RSM). Three potential factors, viz. O2 flowrate (A), ZnO loading (B) and initial concentration of POME (C) were evaluated for the significance analysis using a 2(3) full factorial design before the optimization process. It is found that all the three main factors were significant, with contributions of 58.27% (A), 15.96% (B) and 13.85% (C), respectively, to the POME degradation. In addition, the interactions between the factors AB, AC and BC also have contributed 4.02%, 3.12% and 1.01% to the POME degradation. Subsequently, all the three factors were subjected to statistical central composite design (CCD) analysis. Quadratic models were developed and rigorously checked. A 3D-response surface was subsequently generated. Two successive validation experiments were carried out and the degradation achieved were 55.25 and 55.33%, contrasted with 52.45% for predicted degradation value.
Microbial fuel cells (MFCs) are considered as promising technology to achieve simultaneous wastewater treatment and electricity generation. However, operational and technological developments are still required to make it as a sustainable technology. In the present study, response surface methodology (RSM) was used to evaluate the effects of substrate concentration, co-culture composition, pH and time on the performance of co-culture (Klebsiella variicola and Pseudomonas aeruginosa) inoculated double chamber MFC. From the statistical analysis, it can be seen that the performance of MFC was not influenced by the interaction between the initial COD and time, pH and time, pH and initial COD, time and initial COD. However, the interaction between the inoculum composition and time, pH and the inoculum composition, initial COD and inoculum composition significantly influenced the performance of MFC. Based on the RSM results, best performance (power density and COD removal efficiency) was obtained when the inoculum composition, initial COD, pH and time were about 1:1, 26.690 mg/L, 7.21 and 15.50 days, respectively. The predictions from the model were in close agreement with the experimental results suggesting that the proposed model could adequately represent the actual relationships between the independent variables generating electricity and the COD removal efficiency.
For decades, water treatment plants in Malaysia have widely employed aluminium-based coagulant for the removal of colloidal particles in surface water. This generates huge amount of by-product, known as sludge that is either reused for land applications or disposed to landfills. As sludge contains high concentration of aluminium, both can pose severe environmental issues. Therefore, this study explored the potential to recover aluminium from water treatment sludge using acid leaching process. The evaluation of aluminium recovery efficiency was conducted in two phases. The first phase used the one factor at a time (OFAT) approach to study the effects of acid concentration, solid to liquid ratio, temperature and heating time. Meanwhile, second phase emphasized on the optimization of aluminium recovery using Response Surface Methodology (RSM). OFAT results indicated that aluminium recovery increased with the rising temperature and heating time. Acid concentration and solid to liquid ratio, however, showed an initial increment followed by reduction of recovery with increasing concentration and ratio. Due to the solidification of sludge when acid concentration exceeded 4 M, this variable was fixed in the optimization study. RSM predicted that aluminium recovery can achieve 70.3% at optimal values of 4 M, 20.9%, 90 °C and 4.4 h of acid concentration, solid to liquid ratio, temperature and heating time, respectively. Experimental validation demonstrated a recovery of 68.8 ± 0.3%. The small discrepancy of 2.2 ± 0.4% between predicted and validated recovery suggests that RSM was a suitable tool in optimizing aluminium recovery conditions for water treatment sludge.
Palm oil sludge (POS) is an organic waste generated from the palm oil industry. POS causes environmental pollution if it is improperly disposed. In this study, the potential of activated POS biochar, as an adsorbent for the removal of SO2 gas was tested. POS biochar was physically activated using CO2 gas. The effects of activation preparation variables i.e. activation temperature (300-700 °C), activation time (30-150 min) and CO2 flow rate (100-500 ml/min) were investigated using design expert version 8.0.7.1 software. Central Composite Design (CCD) was used to develop a quadratic model to correlate the operating variables with the activated biochar adsorption capacity. Analysis of variance (ANOVA) was performed to identify the significant factors on the experimental design response. The optimum preparation conditions of activated POS biochar were found to be at activation temperature of 442 °C, activation time of 63 min and CO2 flow rate of 397 ml/min. The maximum adsorption capacity at the optimum conditions was recorded as 16.65 mg/g. The adsorption capacity increased significantly after the activation process. Characteristics of the activated POS biochar proposed that SO2 was physically adsorbed. Furthermore, it was found that the adsorption capacity can be further enhanced by increasing the reaction temperature to 100 °C or with 15% of relative humidity in the inlet gas. The prepared adsorbents can be regenerated by thermal treatment.
Palms are iconic plants. Oil palms are very important economically and originate in Africa where they can act as a model for palms in general. The effect of future climate on the growth of oil palm will be very detrimental. Latitudinal migration of tropical crops to climate refuges may be impossible, and longitudinal migration has only been confirmed for oil palm, of all the tropical crops. The previous method to determine the longitudinal trend for oil palm used the longitudes of various countries in Africa and plotted these against the percentage suitable climate for growing oil palms in each country. An increasing longitudinal trend was observed from west to east. However, the longitudes of the countries were randomly distributed which may have introduced bias and the procedure was time consuming. The present report presents an optimised and systematic procedure that divided the regions, as presented on a map derived from a CLIMEX model, into ten equal sectors and the percentage suitable climates for growing oil palm were determined for each sector. This approach was quicker, systematic and straight forward and will be useful for management of oil palm plantations under climate change. The method confirmed and validated the trends reported in the original method although the suitability values were often lower and there was less spread of values around the trend. The values for the CSIRO MK3.0 and MIROC H models demonstrated considerable similarities to each other, contributing to validation of the method. The procedure of dividing maps equally into sectors derived from models, could be used for other crops, regions, or systems more generally, where the alternative may be a more superficial visual examination of the maps. Methods are required to mitigate the effects of climate change and stakeholders need to contribute more actively to the current climate debate with tangible actions.
The production of natural biopolymers as flocculants for water treatment is highly desirable due to their inherent low toxicity and low environmental footprint. In this study, bio-flocculants were extracted from Hibiscus/Abelmoschus esculentus (okra) by using a water extraction method, and the extract yield and its performance in sludge dewatering were evaluated. Single factor experimental design was employed to obtain the optimum conditions for extraction temperature (25-90 °C), time (0.25-5 h), solvent loading (0.5-5 w/w) and agitation speed (0-225 rpm). Results showed that extraction yield was affected non-linearly by all experimental variables, whilst the sludge dewatering ability was only influenced by the temperature of the extraction process. The optimum extraction conditions were obtained at 70 °C, 2 h, solvent loading of 2.5 w/w and agitation at 200 rpm. Under the optimal conditions, the extract yield was 2.38%, which is comparable to the extraction of other polysaccharides (0.69-3.66%). The bio-flocculants displayed >98% removal of suspended solids and 68% water recovery during sludge dewatering, and were shown to be comparable with commercial polyacrylamide flocculants. This work shows that bio-flocculants could offer a feasible alternative to synthetic flocculants for water treatment and sludge dewatering applications, and can be extracted using only water as a solvent, minimising the environmental footprint of the extraction process.
Oleochemicals industry effluence mainly contains a high chemical oxygen demand (COD) in a range of 6000-20,000 ppm. An effective biological wastewater treatment process must be carried out before wastewater is discharged into the environment. In this study, a submerged bed biofilm reactor (SBBR) was adapted to the biological oleochemical wastewater treatment plant observed in the present study. The effect of wastewater flow rate (100-300 mL/min), Cosmoball® percentage in the SBBR system (25-75%), and percentage of activated sludge (0-50%) were investigated in terms of COD reduction. The Box-Behnken design was used for response surface methodology (RSM) and to create a set of 18 experimental runs, which was needed for optimising the biological oleochemical wastewater treatment. A quadratic polynomial model with estimated coefficients was developed to describe COD reduction patterns. The analysis of variance (ANOVA) shows that the wastewater flow rate was the most effective factor in reducing COD, followed by activated sludge percentage and Cosmoball® carrier percentage. Under the optimum conditions (i.e., a wastewater flow rate of 103.25 mL/min a Cosmoball® carrier percentage of 71.94%, and an activated sludge percentage of 40.50%) a COD reduction of 98% was achieved. Thus, under optimum conditions, as suggested by the BBD, SBBR systems can be used as a viable means of biological wastewater treatment in the oleochemicals industry.
Oilfield produced water (OPW) is one of the most important by-products, resulting from oil and gas exploration. The water contains a complex mixture of organic and inorganic compounds such as grease, dissolved salt, heavy metals as well as dissolved and dispersed oils, which can be toxic to the environment and public health. This article critically reviews the complex properties of OPW and various technologies for its treatment. They include the physico-chemical treatment process, biological treatment process, and physical treatment process. Their technological strengths and bottlenecks as well as strategies to mitigate their bottlenecks are elaborated. A particular focus is placed on membrane technologies. Finally, further research direction, challenges, and perspectives of treatment technologies for OPW are discussed. It is conclusively evident from 262 published studies (1965-2021) that no single treatment method is highly effective for OPW treatment as a stand-alone process however, conventional membrane-based technologies are frequently used for the treatment of OPW with the ultrafiltration (UF) process being the most used for oil rejection form OPW and oily waste water. After membrane treatment, treated effluents of the OPW could be reused for irrigation, habitant and wildlife watering, microalgae production, and livestock watering. Overall, this implies that target pollutants in the OPW samples could be removed efficiently for subsequent use, despite its complex properties. In general, it is however important to note that feed quality, desired quality of effluent, cost-effectiveness, simplicity of process are key determinants in choosing the most suitable treatment process for OPW treatment.
Climate change has significantly altered the characteristics of climate zones, posing considerable challenges to ecosystems and biodiversity, particularly in Borneo, known for its high species density per unit area. This study aimed to classify the region into homogeneous climate groups based on long-term average behavior. The most effective parameters from the high-resolution daily gridded Princeton climate datasets spanning 65 years (1950-2014) were utilized, including rainfall, relative humidity (RH), temperatures (Tavg, Tmin, Tmax, and diurnal temperature range (DTR)), along with elevation data at 0.25° resolution. The FCM clustering method outperformed K-Mean and two Ward's hierarchical methods (WardD and WardD2) in classifying Borneo's climate zones based on multi-criteria assessment, exhibiting the lowest average distance (2.172-2.180) and the highest compromise programming index (CPI)-based correlation ranking among cluster averages across all climate parameters. Borneo's climate zones were categorized into four: 'Wet and cold' (WC) and 'Wet' (W) representing wetter zones, and 'Wet and hot' (WH) and 'Dry and hot' (DH) representing hotter zones, each with clearly defined boundaries. For future projection, EC-Earth3-Veg ranked first for all climate parameters across 961 grid points, emerging as the top-performing model. The linear scaling (LS) bias-corrected EC-Earth3-Veg model, as shown in the Taylor diagram, closely replicated the observed datasets, facilitating future climate zone reclassification. Improved performance across parameters was evident based on MAE (35.8-94.6%), MSE (57.0-99.5%), NRMSE (42.7-92.1%), PBIAS (100-108%), MD (23.0-85.3%), KGE (21.1-78.1%), and VE (5.1-9.1%), with closer replication of empirical probability distribution function (PDF) curves during the validation period. In the future, Borneo's climate zones will shift notably, with WC elongating southward along the mountainous spine, W forming an enclave over the north-central mountains, WH shifting northward and shrinking inland, and DH expanding northward along the western coast. Under SSP5-8.5, WC is expected to expand by 39% and 11% for the mid- and far-future periods, respectively, while W is set to shrink by 46%. WH is projected to expand by 2% and 8% for the mid- and far-future periods, respectively. Conversely, DH is expected to expand by 43% for the far-future period but shrink by 42% for the mid-future period. This study fills a gap by redefining Borneo's climate zones based on an increased number of effective parameters and projecting future shifts, utilizing advanced clustering methods (FCM) under CMIP6 scenarios. Importantly, it contributes by ranking GCMs using RIMs and CPI across multiple climate parameters, addressing a previous gap in GCM assessment. The study's findings can facilitate cross-border collaboration by providing a shared understanding of climate dynamics and informing joint environmental management and disaster response efforts.
Putrajaya Wetlands in Malaysia, a 200ha constructed wetland system consisting of 24 cells, was created in 1997-1998 to treat surface runoff caused by development and agricultural activities from an upstream catchment before entering Putrajaya Lake (400ha). It was designed for stormwater treatment, flood control and amenity use. The water quality improvement performance of a section of the wetland cells is described. The nutrient removal performance was 82.11% for total nitrogen, 70.73% for nitrate-nitrogen and 84.32% for phosphate, respectively, along six wetland cells from Upper North UN6 to UN1 from April to December 2004. Nutrient removal in pilot scale tank systems, simulating a constructed wetland and planted with examples of common species at Putrajaya, the Common Reed Phragmites karka and Tube Sedge Lepironia articulata, and the capacity of these species to retain nutrients in above and below-ground plant biomass and substrate is reported. The uptake of nutrients by the Common Reed and Tube Sedge from the pilot tank system was 42.1% TKN; 28.9% P and 17.4% TKN; 26.1% P, respectively. The nutrient uptake efficiency of the Common Reed was higher in above-ground than in below-ground tissue. The results have implications for plant species selection in the design of constructed wetlands in Malaysia and for optimizing the performance of these systems.
Application of urea manufacturing wastewater to teak (Tectona grandis) trees, a fast growing tropical timber plants, is an environmentally-friendly and cost-effective alternative for treatment of nitrogen-rich wastewater. However, the plant growth is strongly limited by lack of phosphorus (P) and potassium (K) elements when the plants are irrigated with wastewater containing high concentration of nitrogen (N). A greenhouse experiment was conducted to optimize the efficiency of teak-based remediation systems in terms of nutrient balance. Twelve test solutions consisted of 4 levels of P (95, 190, 570, 1140 mgL-1) and 3 levels of K (95, 190, 570 mgL-1) with a constant level of N (190 mgL-1) were applied to teak seedlings every four days during the study period. Evapotranspiration rate, nutrient removal percentage, leaf surface area, dry weight and nutrient contents of experimental plants were determined and compared with those grown in control solution containing only N (N:P:K = 1:0:0). Teak seedlings grown in units with 1:0.5:1 N:P:K ratio were highly effective at nutrient removal upto 47%, 48% and 49% for N, P and K, respectively. Removal efficiency of teak plants grown in other experimental units decreased with increasing P and K concentrations in test solutions. The lowest nutrient removal and plant growth were recorded in units with 1:6:0.5 N:P:K ratio which received the highest ratio of P to K. The findings indicated that teak seedlings functioned effectively as phytoremediation plants for N-rich wastewater treatment when they were being supplied with proper concentrations of P and K.
Growing concerns of water pollution by dye pollutants from the textile industry has led to vast research interest to find green solutions to address this issue. In recent years, heterogeneous photocatalysis has harvested tremendous attention from researchers due to its powerful potential applications in tackling many important energy and environmental challenges at a global level. To fully utilise the broad spectrum of solar energy has been a common aim in the photocatalyst industry. This study focuses on the development of an efficient, highly thermal and chemical stable, environmentally friendly and metal-free graphitic carbon nitride (g-C3N4) to overcome the problem of fast charge recombination which hinders photocatalytic performances. Nitrogen-doped carbon quantum dots (NCQDs) known for its high electronic and optical functionality properties is believed to achieve photocatalytic enhancement by efficient charge separation through forming heterogeneous interfaces. Hence, the current work focuses on the hybridisation of NCQDs and g-C3N4 to produce a composite photocatalyst for methylene blue (MB) degradation under LED light irradiation. The optimal hybridisation method and the mass loading required for maximum attainable MB degradation were systematically investigated. The optimum photocatalyst, 1 wt% NCQD/g-C3N4 composite was shown to exhibit a 2.6-fold increase in photocatalytic activity over bare g-C3N4. Moreover, the optimum sample displayed excellent stability and durability after three consecutive degradation cycles, retaining 91.2% of its original efficiency. Scavenging tests were also performed where reactive species, photon-hole (h+) was identified as the primary active species initiating the pollutant degradation mechanism. The findings of this study successfully shed light on the hybridisation methods of NCQDs which improve existing g-C3N4 photocatalyst systems for environmental remediation by utilising solar energy.
The triple components of energy consumption, carbon dioxide emissions, and economic expansion are important to achieving sustained economic activity and sound ecological advancement. This study aims to estimate the impact of wide-ranging parameters on environmental circumstances in South Asian countries. This analysis required two approaches: 1)quantile autoregressive distributed lag (QARDL) as an econometric model, and 2) data envelopment analysis (DEA) non-parametric comparable composite index to examine concurrently South Asian nations' data for the 2000-2018 period. The underscored category of the parameters were grouped into four key indices, namely financial, fiscal, human, and energy. The DEA's mathematical composite findings reveal varied circumstances regarding environmental self-maintenance in South Asian nations. India and Pakistan are doing quite well; Afghanistan is abysmal. In addition, the QARDL approach findings reveal that energy use and fiscal indicators abate pollution. Furthermore, the correlation between fiscal decentralization and ecological attributes is strengthened by the excellent level of institutions and human capital progress. There is a unidirectional impact emanating from fiscal devolution, gross domestic product, human capital, eco-innovation, and institutional excellence on carbon dioxide pollution, although different from the other correlations obtained.
A new effective adsorbent, 3-aminopropyltrimethoxysilane functionalized magnetic sporopollenin (MSp@SiO2NH2) based silica-coated graphene oxide (GO), (GO@SiO2-MSp@SiO2NH2) was successfully synthesized and applied for the first time in the removal of hazardous Pb(II) ions from aqueous solution. The properties of the composite were characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX) and vibrating-sample magnetometery (VSM). Evaluation of GO@SiO2-MSp@SiO2NH2 adsorption performance at optimum conditions revealed that the adsorbent has a maximum adsorption capacity of 323.5 mg/g for Pb(II) using 50-200 mg/L initial Pb(II) ions concentrations. Initial and final concentrations of Pb(II) ions in aqueous solution were analyzed using graphite furnace atomic absorption spectroscopy (GF-ASS). The adsorption behavior of Pb(II) ions onto GO@SiO2-MSp@SiO2NH2 was studied using Langmuir, Freundlich and Temkin isotherms models. The values of coefficient of determination showed that the adsorption best fitted the Langmuir model (R2 = 0.9994). Kinetic studies suggested that the adsorption of Pb(II) ion followed a pseudo-second-order rate model (R2 = 1.00) and thermodynamic studies revealed that the adsorption process is endothermic and spontaneous. The effect of co-existing ions on Pb(II) ion adsorption were also studied and found to have considerable effects only at higher matrix concentration. The adsorbent can be reused up to ten times and retain its good adsorption capacity. In addition, GO@SiO2-MSp@SiO2NH2 showed great potential for Pb(II)removal from industrial wastewater samples.
Forest growth models are useful tools for investigating the long-term impacts of logging. In this paper, the results of the rain forest growth model FORMIND were assessed by a multicriteria decision analysis. The main processes covered by FORMIND include tree growth, mortality, regeneration and competition. Tree growth is calculated based on a carbon balance approach. Trees compete for light and space; dying large trees fall down and create gaps in the forest. Sixty-four different logging scenarios for an initially undisturbed forest stand at Deramakot (Malaysia) were simulated. The scenarios differ regarding the logging cycle, logging method, cutting limit and logging intensity. We characterise the impacts with four criteria describing the yield, canopy opening and changes in species composition. Multicriteria decision analysis was used for the first time to evaluate the scenarios and identify the efficient ones. Our results plainly show that reduced-impact logging scenarios are more 'efficient' than the others, since in these scenarios forest damage is minimised without significantly reducing yield. Nevertheless, there is a trade-off between yield and achieving a desired ecological state of logged forest; the ecological state of the logged forests can only be improved by reducing yields and enlarging the logging cycles. Our study also demonstrates that high cutting limits or low logging intensities cannot compensate for the high level of damage caused by conventional logging techniques.
Governance has become indispensable within the healthcare sector, but previous studies have not explored the potential environmental benefits linked to healthcare governance. Thus, this study focuses on the role of governance in moderating healthcare and environmental emissions in 159 low, lower-middle, upper-middle and high-income countries. To do so, cross-sectional autoregressive distributed lag (CS-ARDL) techniques were applied using panel data from 1999 to 2021, followed by the computation of threshold and marginal effect of governance on healthcare and environmental emissions nexus. Findings revealed that, with the exception of high-income countries in the short run, governance has an insignificant impact on healthcare and emissions nexus in low-, lower-middle and upper-middle-income countries. Surprisingly, the findings imply that, in the long run, countries with greater levels of governance are likely to have lesser environmental impacts related to healthcare. There was also evidence indicating that low, lower-middle, upper-middle and high-income countries must reach a certain level of governance before realising the benefits of healthcare. Therefore, to achieve lower environmental impacts from healthcare, countries must promote effective governance policies that can incentivise and enforce sustainable practices and technologies in the healthcare sector.
A simplified modelling approach for illustrating the fate of emerging pollutants can improve risk assessment of these chemicals. Once released into aquatic environments, these pollutants will interact with various substances including suspended particles, colloidal or nano particles, which will greatly influence their distribution and ultimate fate. Understanding these interactions in aquatic environments continues to be an important issue because of their possible risk. In this study, bisphenol A (BPA) in the water column of Bentong River, Malaysia, was investigated in both its soluble and colloidal phase. A spatially explicit hydrological model was established to illustrate the associated dispersion processes of colloidal-bound BPA. Modelling results demonstrated the significance of spatial detail in predicting hot spots or peak concentrations of colloidal-bound BPA in the sediment and water columns as well. The magnitude and setting of such spots were system based and depended mainly on flow conditions. The results highlighted the effects of colloidal particles' concentration and density on BPA's removal from the water column. It also demonstrated the tendency of colloidal particles to aggregate and the impact all these processes had on BPA's transport potential and fate in a river water. All scenarios showed that after 7.5-10 km mark BPA's concentration started to reach a steady state with very low concentrations which indicated that a downstream transport of colloidal-bound BPA was less likely due to minute BPA levels.