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The utilization of metal-based conventional coagulants/flocculants to remove suspended solids from drinking water and wastewater is currently leading to new concerns. Alarming issues related to the prolonged effects on human health and further pollution to aquatic environments from the generated nonbiodegradable sludge are becoming trending topics. The utilization of biocoagulants/bioflocculants does not produce chemical residue in the effluent and creates nonharmful, biodegradable sludge. The conventional coagulation–flocculation processes in drinking water and wastewater treatment, including the health and environmental issues related to the utilization of metal-based coagulants/flocculants during the processes, are discussed in this paper. As a counterpoint, the development of biocoagulants/bioflocculants for drinking water and wastewater treatment is intensively reviewed. The characterization, origin, potential sources, and application of this green technology are critically reviewed. This review paper also provides a thorough discussion on the challenges and opportunities regarding the further utilization and application of biocoagulants/bioflocculants in water and wastewater treatment, including the importance of the selection of raw materials, the simplification of extraction processes, the application to different water and wastewater characteristics, the scaling up of this technology to a real industrial scale, and also the potential for sludge recovery by utilizing biocoagulants/bioflocculants in water/wastewater treatment.

Increasing levels of bisphenol A (BPA), classified as an endocrine-disrupting compound, in the environment have raised concerns because of its detrimental impact on human and animal health. BPA has been detected in soil and water and even as a volatile compound in the air primarily because of improper disposal and its extensive use in the production of polycarbonate plastics and epoxy resins. This review comprehensively surveyed recent research focusing on the removal of BPA from water through physicochemical and biological treatments, covering articles published from 2002 to 2023. A range of conventional and non-conventional methods employed for BPA removal is examined, and their limitations in completely degrading BPA in water are acknowledged. Hybrid or integrated treatment systems have been explored, capitalising on the distinctive removal potential of various treatment processes. The literature spanning from 2002 to 2023 underscores the efficacy of hybrid or integrated treatment systems in yielding promising results for BPA removal from water. Furthermore, future directions for BPA removal are outlined, and advancements in treatment technologies developed over the past decade are incorporated.

Researchers in recent years have utilized a broad spectrum of treatment technologies in treating bakers’ yeast production wastewater. This paper aims to review the treatment technologies for the wastewater, compare the process technologies, discuss recent innovations, and propose future perspectives in the research area. The review observed that nanofiltration was the most effective membrane process for the treatment of the effluent (at >95% pollutant rejection). Other separation processes like adsorption and distillation had technical challenges of desorption, a poor fit for high pollutant load and cost limitations. Chemical treatment processes have varying levels of success but they are expensive and produce toxic sludge. Sludge production would be a hurdle when product recovery and reuse are targeted. It is difficult to make an outright choice of the best process for treating the effluent because each has its merits and demerits and an appropriate choice can be made when all factors are duly considered. The process intensification of the industrial-scale production of the bakers’ yeast process will be a very direct approach, where the process optimisation, zero effluent discharge, and enhanced recovery of value-added product from the waste streams are important approaches that need to be taken into account.

Leachate is produced from sanitary landfills containing various pollutants, including heavy metals. This study aimed to determine the resistance of bacteria isolated from non-active sanitary landfill leachate to various heavy metals and the effect of salinity levels on the removal of Hg by the isolated bacterium. Four dominant bacteria from approximately 33 × 10 17 colony-forming units per mL identified as Vibrio damsela , Pseudomonas aeruginosa , Pseudomonas stutzeri , and Pseudomonas fluorescens were isolated from non-active sanitary landfill leachate. Heavy metal resistance test was conducted for Hg, Cd, Pb, Mg, Zn, Fe, Mn, and Cu (0–20 mg L − 1 ). The removal of the most toxic heavy metals by the most resistant bacteria was also determined at different salinity levels, i.e., fresh water (0‰), marginal water (10‰), brackish water (20‰), and saline water (30‰). Results showed that the growth of these bacteria is promoted by Fe, Mn, and Cu, but inhibited by Hg, Cd, Pb, Mg, and Zn. The minimum inhibitory concentration (MIC) of all the bacteria in Fe, Mn, and Cu was > 20 mg L − 1 . The MIC of V. damsela was 5 mg L − 1 for Hg and >  20 mg L − 1 for Cd, Pb, Mg, and Zn. For P. aeruginosa , MIC was > 20 mg L − 1 for Cd, Pb, Mg, and Zn and 10 mg L − 1 for Hg. Meanwhile, the MIC of P. stutzeri was > 20 mg L − 1 for Pb, Mg, and Zn and 5 mg L − 1 for Hg and Cd. The MIC of P. fluorescens for Hg, Pb, Mg, and Zn was 5, 5, 15, and 20 mg L − 1 , respectively, and that for Cd was > 20 mg L − 1 . From the MIC results, Hg is the most toxic heavy metal. In marginal water (10‰), P. aeruginosa FZ-2 removed up to 99.7% Hg compared with that in fresh water (0‰), where it removed only 54% for 72 h. Hence, P. aeruginosa FZ-2 is the most resistant to heavy metals, and saline condition exerts a positive effect on bacteria in removing Hg.

Chromium (Cr) is used as a mixture to improve strength and corrosion resistance. Milling and welding processes can expose workers to Cr through dermal exposure and inhalation. Cr exposure can be determined by urine testing. The purpose of this study was to analyze the concentration of Cr in urine (UCr) of workers. This study was carried out using a cross-sectional method. Sampling was conducted in the village of Mekarmaju, Bandung, Indonesia. The number of respondents included 30 blacksmiths, and the control group comprised 10 people who were not blacksmiths. Cr 6+ exposure was measured using a personal sampling pump placed on the collar of the worker’s shirt as a breathing zone and then analyzed using a UV–visible spectrophotometer. UCr was measured with a graphite furnace atomic absorption spectrophotometer. The measured Cr 6+ concentration in the exposed working area ranged from 0.03 to 0.63 mg/m 3 , whereas that in non-exposed area ranged from 0.02 to 0.04 mg/m 3 . Results showed that 16 out of 30 blacksmiths had a UCr concentration above the biological exposure index (BEI) value, 21 had a higher value than the threshold limit value (TLV), and 22 had hazard index (HI) values > 1, which indicated that Cr has a hazardous potential in the body. The analysis of the exposed and control groups showed a significant difference with a p value of 0.000 for TLV, chronic daily intake, and UCr. These results clearly showed that Cr 6+ exposure may harm the health of these workers in the future. The results obtained in this study can be used to promote workers’ awareness on the potential health risk caused by Cr 6+ exposure in the working environment.

Domestic wastewater discharge is the major source of pollution in Malaysia. Phytoremediation under hydroponic conditions was initiated to treat domestic wastewater and, at the same time, to resolve the space limitation issue by installing a hydroponic system in vertical space at the site. Water hyacinth (WH) was selected in this study to identify its performance of water hyacinth in removing nutrients in raw sewage under batch operation. In the batch experiment, the ratio of CODinitial/plantinitial was identified, and SPSS ANOVA analysis shows that the number of plant size factors was not statistically different in this study. Therefore, four WH, each with an initial weight of 60 ± 20 g, were recommended for this study. Throughout the 10 days of the batch experiment, the average of COD, BOD, TSS, TP, NH4, and color removal was 73%, 73%, 86%, 79%, 77%, and 54%, respectively. The WH biomass weight increased by an average of 78%. The plants have also improved the DO level from 0.24 mg/L to 4.88 mg/L. However, the pH of effluent decreased from pH 7.05 to pH 4.88 below the sewage Standard B discharge limit of pH 9–pH 5.50. Four WH plant groups were recommended for future study, as the COD removal among the other plant groups is not a statistically significant difference (p < 0.05). Furthermore, the lower plant biomass is preferable for the high pollutant removal performance due to the fact that it can reduce the maintenance and operating costs.

Open burning is a waste management practice performed by many people worldwide, especially in developing countries. Lack of detailed data of open burning practices may lead to a misinterpretation during data analysis, especially when estimating global/local emissions and assessing risks. This study presents a comprehensive review of current research trends, methodological assessments, and factors behind open waste burning practices from published literature. This review used systematic methods such as PRISMA 2020 methodology, a bibliometric approach, and qualitative content analysis to determine and assess 84 articles related to open burning. The results show that environmental risks and emission factors related to open burning incidents at the landfill or residential level are preferable topics that will be rising in the years to come. Coupling methods such as a transect-based approach with a questionnaire survey and mobile-static plume sampling to determine the activities and incidents as baseline data for risk assessment will help researchers gain a robust dataset of open burning emission inventory. In addition, it was found that environmental knowledge and awareness levels influence open burning practices, thereby opening up opportunities for future research.

The purpose of this research was to investigate the accumulation of plastic debris in the Wonorejo River Estuary, Surabaya, Indonesia. Visible plastic debris were collected from three (3) sampling points along the intertidal area of Wonorejo River Estuary. The correlation between sampling points (SPs) and the amount of the collected plastic debris (CPD) was analysed using one-way ANOVA. Result of one-way ANOVA showed that the sampling point was significantly affect the amount of the collected plastic debris (p<0.05). A further analysis using Tukey’s Significance Honest Test indicating a significantly higher CPD on SP2 compared to the SP1 and SP3 ( p <0.05). The amount of CPD were 126.07±12.00 g dry weight/m 2 from SP1, 375.97±16.72 g dry weight/m 2 from SP2, and 291.13±36.28 g dry weight/m 2 from SP3. The highest percentage of collected debris item was plastic bags (up to 57.90%), followed by bottle caps (up to 16.65%). The most identified plastic types were Low-Density Polyethylene (LDPE) (up to 73.13%), followed by Polypropylene (PP) (up to 17.22%). Understanding the accumulation of plastic debris in estuary is a fundamental requirement to conduct an advance research related to the marine plastic pollution and to determine further actions to solve this problem.

The presence of ibuprofen (IBP) and paracetamol (PAR) contaminants in wastewater has become an emerging issue. Traditional wastewater treatment facilities have not been adequately upgraded to remove these micropollutants. This study focused on screening and identifying effective rhizobacteria capable of assisting plants in eliminating ibuprofen and paracetamol from wastewater using constructed wetlands. A total of 28 rhizobacteria were isolated from both the roots and the surrounding sand of Scirpus grossus after 30 days of pharmaceutical exposure. Among these, three isolates (Gram-negative Enterobacter aerogenes, Gram-positive Bacillus flexus, and Paenibacillus alvei) showed high tolerance to IBP and PAR with initial removal efficiencies > 75%. The addition of these three isolated rhizobacteria to a constructed wetland (planted with Scirpus grossus, 5-day HRT, 2 L/min aeration) assists the removal of IBP and PAR from wastewater. Bioaugmentation of rhizobacteria showed an increment of IBP removal (↑13%) from water (residual of 10 µg/L) and PAR (↑20%) from sand (residual 2.3 µg/L) as compared to the non-bioaugmented systems. The addition of rhizobacteria also showed the ability to significantly enhance the translocation of PAR into the shoot system of S. grossus, suggesting assisted phytoextraction mechanisms, while the removal of IBP in wetlands is suggested to occur via rhizodegradation. It is recommended that future research be conducted to elucidate the microbial degradation pathways and analyze the intermediate metabolites to accurately depict the pharmaceutical degradation mechanisms and evaluate their ecological risks.

The study aimed to address the critical problem of malathion pesticide contamination in agricultural runoff and its adverse impact on the environment. It specifically focused on utilizing granular activated carbon (GAC), derived from both coal (CBAC) and peat (PBAC), as a promising solution for effective malathion removal. This study focused on the substantial influence of particle size and GAC dosage on the removal efficiency of malathion. It was determined that optimal conditions, resulting in an impressive 90% removal efficiency, were achieved when the initial malathion concentration of 7 μg L -1 was reduced to approximately 1.14 μg L -1 and 1.5 μg L -1 for CBAC with particle sizes of 0.063 mm and 1.0 mm, respectively. In contrast, PBAC exhibited a removal efficiency of 2.87 μg L -1 under similar conditions. The study further employed the Langmuir and Freundlich adsorption isotherms models to analyze the adsorption behavior of malathion on GAC. The equilibrium data closely aligned with both models, and the maximum adsorption capacity was determined to be an impressive 248.1 mg g -1 . These findings highlight the significant potential of GAC, whether coal or peat-based, as a highly effective absorbent material for mitigating malathion contamination in agricultural runoff. This research contributes to enhancing environmental disaster resilience by offering a viable method for optimizing GAC use, thereby reducing the detrimental effects of pesticide contamination on the environment.