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Although investigation of microplastics (MPs) present in air environment has been intensively carried out, quantification, characteristics, and distribution of MPs released from the waste burning furnace (WBF) has been missing in literature. The aim of this study was to characterize the presence of MPs released from WBFs and analyze their associated health impacts. The examined locations were at two WBFs (nominated as TPS1 and TPS2) in Sidoarjo, Indonesia. MPs were collected using a 9 cm diameter glass beaker for a period of 8 h at two different sampling points, which are 3 and 15 m from each WBF. Several characteristics of MPs in terms of the number of particles, size, shape, color, and polymer type were comprehensively characterized. This study found that the obtained MPs were of fiber type and in the range of 46–77 and 41–59 particles at TPS1 and TPS2, respectively. In general, the polymer types of MPs were, respectively, cellophane and polytetrafluoroethylene at TPS1 and TPS2. Moreover, it was estimated that about 1.9–2.3 MPs can enter the human body via inhalation. This study offers a pilot examination of MPs released from WBF and findings from this study are crucial to provide new knowledge as a basis to carefully regulate the use of WBF particularly that are located closely to local community. [ABSTRACT FROM AUTHOR]

Various waste management strategies have been discussed by the above-mentioned collection of articles including the use of eco-enzymes, flood management, heavy metal pollution management, and the circular economy concept in waste management in developing countries. HEAVY METAL REMOVAL Heavy metal removal in the ecosystem is described in the following six articles. Ratnasari et al. ([19]) evaluated a powerful and flexible mathematical model, modified mass transfer factor model (MMTF), for describing the mechanism of numerous heavy metal and dye pollutants adsorbed onto various adsorbents. The special issue carries 27 articles exploring various aspects of environmental quality including nano adsorbent, waste management, wastewater treatment, and heavy metal removal. [Extracted from the article]

This study focuses on the settling profile and chemical characteristics of latex aerobic granules cultivated from rubber industrial wastewater. Latex‐based aerobic granular sludge (AGS) was cultivated using sequencing batch reactor (SBR) in supplemented with synthetic wastewater (SW) as nutrients feeding for biogranulation process. The bioreactor was operated for 24 h with eight series of intermittent 3 h SBR cycles continuously. The SBR configuration comprises of five operation phases from SW feeding, aeration, settling, and effluent decanting to idle. Latex granules exhibit a loose and irregular structure dominated by coccal‐shaped bacteria with an average size of 4.0–5.0 mm and a settling velocity of 0.35–0.53 m h–1. The elemental analysis using X‐ray fluorescence (XRF) showed that the latex granules contained various elements while X‐Ray diffraction (XRD) analysis suggested the presence of zincowoodwardite, berlinite, rutile, and quartz. Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of aliphatic hydrocarbons, alkene, alkyne, and tertiary amine. [ABSTRACT FROM AUTHOR]

Exposure of carbon monoxide (CO) released by insect repellent has a negative impact on health by forming carboxyhemoglobin (CO‐Hb) as a trigger for oxidative stress in the human body. Therefore, the objective of the study was to investigate the effect of commercial anti‐mosquitos on CO‐Hb and malondialdehyde (MDA) levels in the blood. Effect of electric spray, coils, and electric mats on CO‐Hb and MDA levels in blood was evaluated using male Wistar rats (8 h per day) and monitored for 20 days. The study found that the highest increase in CO‐Hb and CO‐Hb levels in the blood was observed when exposed to electric spray formula compared to other anti‐mosquitos. In addition, the highest increase in MDA levels also occurred when exposed to the electric spray. Statistical analysis revealed that there was a significant relationship between CO‐Hb and MDA levels in the blood (p‐value = 0.000). High CO‐Hb levels in the blood could stimulate oxidative stress and lead to cell damage in the body. [ABSTRACT FROM AUTHOR]

This study aimed to analyze water quality and control water pollution in the Pucang River in Sidoarjo Regency. The method was used to identify water quality of the 11 parameters and compared them the Government Regulation number 22 of 2021 about water quality standards in Indonesia. Secondary data from 2018 to 2020 were used in this study. Determination of water quality status using the pollution indices method attached in Decree of the State Minister of the Environment number 115 of 2003. Analysis of water pollution control strategies using strengths, weaknesses, opportunities, and threats approach. The condition of the water quality of the Pucang River in 2018–2020, based on the water pollution parameter test, experienced a decrease in the rate indicated by the presence of parameters that exceeded the quality standard. Determination of the quality status of water quality in 2018–2020, there was an increase in water quality marked by the rise in the pollution indices value where the water quality was moderately polluted heavily polluted. The conclusion is that the water quality of the Pucang River in 2018–2020 has decreased from the moderately polluted category to the heavily polluted, and the condition of river water cannot be used for its designation. [ABSTRACT FROM AUTHOR]

In textile industries, residual dyes and heavy metals are usually released into environment via wastewater effluent. Because of their negative effects not only to environment but also to human health, these contaminants are required to be removed from water environment. To achieve the effective adsorption of dye and heavy metal, the adsorption mechanism needs to be understood clearly. In this study, the complexity of adsorption of Remazol brilliant blue R (RBBR), methyl orange (MO), copper (Cu) ions, and iron (Fe) ions onto numerous natural adsorbents was analyzed using the modified mass transfer factor model (MMTF). The secondary adsorption data were collected from various sources. The study found that MMTF has a superior adaptability for describing the mechanism of the adsorption of dyes and heavy metals both in solely and in multi solute. [ABSTRACT FROM AUTHOR]

To elucidate the efficacy of eco‐enzyme in mediating contaminated waters, an onsite investigation was conducted spanning over a 5‐month duration on three ponds receiving iron‐containing groundwater continuously. Eco‐enzyme was applied at designated dosages and time. Water samples were collected fortnightly for in situ monitoring of water quality. Parameters determined included total suspended solids (TSS), pH, alkalinity, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), ammoniacal‐nitrogen (NH3), and dissolved oxygen. During the investigation, eco‐enzyme application was halted for nearly a month owing to the enforcement of Movement Control Order to curb the rising Covid‐19 cases. The results revealed that the application of eco‐enzyme has improved the overall water quality of the three ponds. A 99.9% of TSS removal was achieved. For the other parameters measured, the concentration fluctuated over time and the water quality status of the pond interchanged between slightly polluted and clean. The elevation of the water quality was largely dependent on the frequency of the eco‐enzyme application. This study, therefore, concludes that eco‐enzyme possessed the capability to enhance the quality of contaminated water. [ABSTRACT FROM AUTHOR]

Flood caused by overflowing water from river has become a major issue in Southeast Asia, as it has caused economic losses and deaths. Therefore, the present work aims to propose an alternative approach for morphometric analysis of the Ciliwung River Upper Stream (CRU) without the geographic information system technique use for flood prevention strategy application. For the river network simulation, an agent‐based model having several rules in terms of agent, landscaping, and action was adopted. In addition, the river morphometric characteristics, namely, river network, river order, bifurcation ratio, length‐order ratio, fractal dimension, watershed density, and river capacity were estimated. It was found that the proposed technique was able to estimate the river morphometric characteristics of CRU. CRU has the river order, bifurcation ratio, length‐order ratio, fractal dimension, watershed density, and river capacity of 4, 1.1–2.5, 0.6–1.1, 1.84, 0.01 km km–2, and 1,404,060 L, respectively. It was also identified four suitable locations to build artificial dams for flood prevention strategy by employing the presently proposed technique. The proposed artificial dams with heights ranging from 10 m to 25 m demonstrated to have capability to prevent flood in the capital city of Jakarta, Indonesia. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants (WWTPs) become a main contributor of polycyclic aromatic hydrocarbons (PAHs) and their substitutions present in freshwater systems. This paper reviews PAHs and their substitutions in full‐scale WWTPs including their fate and behaviors, analytical techniques, biological treatments, feasibility examination, and modeling. In addition, challenges and future outlook are also highlighted. This study found that PAHs and their substitutions have been detected in WWTPs. GC‐MS and HPLC analytical methods have been found to be acceptable for the detection and analysis of PAHs and their substitutions. Although some biological treatments such as activated sludge and membrane bioreactors are capable for the treatment process, their technical, social, economic, and environmental aspects must be considered. The fate and treatability estimator (FATE) model has been used for the modeling of removal of PAHs in full‐scale WWTPs, but in some cases their shortcoming has been reported, which calls for an evaluation and modification of the model based on physicochemical processes. [ABSTRACT FROM AUTHOR]

The development of antimicrobial food packaging is needed for food preservation and quality maintenance. Silver nanoparticles (AgNPs) have been widely used as an antimicrobial agent in food packaging technologies. However, the risks associated with their potential migration into foods are a major concern. This paper comprehensively reviews the use of AgNPs in food packaging technologies. The application of AgNPs in food packaging technologies has been regulated by the United States Food and Drug Administration and the European Food Safety Authority. The addition of AgNPs into food packaging can improve their barrier, mechanical, and antibacterial properties, as well as maintain the quality of foods. Migration of AgNPs from food packaging into foods is still a concern as it has implications for human health associated with their toxicity properties. A study on the toxicological properties of AgNPs released from food packaging needs to be carried out intensively to ensure their safety before being widely implemented. Moreover, comprehensive economic evaluation to implement AgNPs in food packaging is needed as such a study is missing in the literature. [ABSTRACT FROM AUTHOR]

This study deals with the synthesis of zeolite from natural kaolinite using hydrothermal treatment and evaluation of its phase transformation behaviors. The synthesized zeolites were modified with silver ion by using the ion exchange method for the enhancement of antibacterial properties. The characterizations were performed by using X‐ray diffraction spectroscopy, Fourier‐transform infrared spectroscopy, field emission scanning electron microscopy, and energy‐dispersive X‐ray. Disk diffusion technique (DDT) was used for the evaluation of the antibacterial property of the modified zeolites. This study observed the transformation of kaolinite into amorphous metakaolin after calcination treatment at 900°C and the successful reconstruction of amorphous metakaolin into synthesized crystal zeolite in the presence of sodium hydroxide as an activating agent. It was also found that the zeolite type A was produced at 100°C, while sodalites were produced at 120 and 140°C. DDT analysis revealed that the modified zeolites showed significant antibacterial capability against Escherichia coli ATCC 11229 and Staphylococcus aureus ATCC 6538. In general, the present study has proven that the zeolites can be synthesized from natural material and can be modified with silver ion to enhance their antibacterial activity. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive understanding of development of textiles functionalized with silver nanoparticles (AgNPs). There are three established methods to fabricate textiles functionalized with AgNPs, namely, solution‐immersion, layer‐by‐layer deposition, and sonochemical. In addition, several textile types such as cotton, wool, polyester, silk, cotton/polyester blend, polyamide, and regenerated cellulose have been used for the fabrication. The AgNP deposition mechanism on textiles is mainly due to electrostatic interaction between AgNPs and textile constituents. It was exhibited that the deposition of AgNPs on textiles can transform their textiles colors. In addition, it was demonstrated that the deposition of AgNPs on textiles is not permanent, particularly against washing treatment. Textiles modified with AgNPs have several promising applications such as antibacterial, antifungal, catalyst, electronic devices, water treatment, sun protection, air treatment, and surface‐enhanced Raman scattering, which are comprehensively discussed in this article. Future challenges in fabricating textiles functionalized with AgNPs remain on how this can be carried out to improve long‐term stabilization of AgNPs on textiles to achieve their permanent deposition by employing greener approaches. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the capability of Ageratum conyzoides and Mikania micrantha extracts to synthesize silver nanoparticles (AgNPs) and their antibacterial capability against gram‐positive and gram‐negative bacteria. Several properties of the synthesized AgNPs, including plasmonic, biomolecule bonding, shape, size, and antibacterial, were investigated. Ultraviolet–visible (UV–vis) spectroscopy was employed for characterizing their plasmonic properties. Functional groups on the produced AgNPs were investigated by Fourier‐transform infrared (FT‐IR) spectroscopy. The size and shape of the AgNPs were identified using the field‐emission scanning electron microscopy (FESEM). Inhibition zone measurement was carried out for evaluating the antibacterial capability. This study showed that the extracts of A. conyzoides and M. micrantha were able reducing agents as evidenced by the formation of the spherical AgNPs. UV–vis spectroscopy, FT‐IR spectroscopy, and FESEM confirmed the physicochemical characteristics of AgNPs. AgNPs that were synthesized using M. micrantha were slightly smaller than those produced using A. conyzoides. In general, the present work establishes that the synthesized AgNPs have antibacterial capability depending on their size and synthesis procedure. [ABSTRACT FROM AUTHOR]

We propose a procedure to remove lead (Pb) via catalytic chelation using peracetic acid (PAA) catalyzed using zinc aluminate (ZnAl2O4) prepared at different calcination temperatures of 900, 1,000, and 1,100 °C. In addition, their characterization in terms of the thermogravimetry analysis‐differential thermal analysis (TGA‐DTA), X‐ray diffraction (XRD), field‐emission scanning electron microscopy‐energy dispersive X‐ray analysis (FESEM‐EDX), Brunauer–Emmett–Teller (BET) analysis, Fourier transform infrared spectroscopy (FTIR), inductively coupled plasma mass spectrometry (ICP‐MS), and X‐ray photoelectron spectroscopy (XPS) was achieved. Moreover, response surface methodology (RSM) was employed for modeling. This study confirms that the properties of ZnAl2O4 are highly influenced by the calcination temperature. In addition, up to 95.3% of Pb can be removed using the proposed approach by employing optimum parameters such as temperature, pH, treatment time, PAA concentration, catalyst loading, and dissolved oxygen. We propose a procedure to remove lead (Pb) via catalytic chelation using peracetic acid (PAA) catalyzed by zinc aluminate (ZnAl2O4) prepared at different calcination temperatures. Up to 95.3% of Pb can be removed by employing optimum parameters such as temperature, pH, treatment time, PAA concentration, catalyst loading, and dissolved oxygen. [ABSTRACT FROM AUTHOR]

The degradation of organic dyes in the presence of modified TiO2 is still under intensive investigation. We report here an evaluation of the photocatalytic activity of nitrogen- (N-) and sulfur- (S-) doped TiO2 for the degradation of phenol and methylene blue (MB). N-doped TiO2 (N-TiO2), S-doped TiO2 (S-TiO2), and N-S-doped TiO2 (N-S-TiO2) were prepared using the sol-gel method. The photocatalytic activity was evaluated in a batch reactor using phenol and MB as models of pollutants. In addition, this investigation was performed using a household lamp as the visible light source. Properties of the synthesized materials in terms of Brunauer-Emmett-Teller (BET) surface analysis, field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), and photocatalytic ability were examined. Our study shows that N-S-TiO2 exhibits better photocatalytic degradation ability for all the considered dyes compared to the other doped TiO2 materials. In conclusion, we have successfully prepared and evaluated the photocatalytic activity of N- and S-doped TiO2 for the degradation of phenol and MB using an ordinary household lamp. [ABSTRACT FROM AUTHOR]

Since textiles have a porous and hydrophilic structure, they are ideal substrates for the settlement and growth of pathogenic bacteria. Therefore, fabrication of hydrophobic textiles to reduce their humidity has the potential to inhibit the growth of bacteria. On this basis, we report here an improvement of the antibacterial capability of textiles coated with TiO2-SiO2/chitosan using hydrophobization. Synthesis of TiO2-SiO2 clusters with chitosan was carried out using the sol-gel technique. In addition, hydrophobization of the textiles using hexadecyltrimethoxysilane (HDTMS) was carried out using a dip-spin coating method. In addition, their characteristics were examined using X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-vis diffuse reflectance spectra (UV-DRS), Fourier transform infrared (FTIR), water contact angle, and antibacterial activity. XRD, SEM, UV-DRS, FTIR, and water contact angle confirmed the physical and chemical properties of the modified textiles. In summary, the present work shows that the hydrophobization of textiles using HDTMS can enhance the antibacterial capability of cotton textiles. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are intensively investigated for their superior physical, chemical, and biological properties. A proper knowledge of these properties is essential to maximizing the potential applications of AgNPs in several areas while minimizing their risks to humans and the environment. This paper aims to critically review AgNPs from the perspectives of research trends, global consumption, synthesis, properties, and future challenges. Generally, AgNPs can be synthesized using three methods, namely physical, chemical, and biological, and the related works as well as their numerous advantages and disadvantages are presented in this review. In addition, AgNPs can be potentially explored for various applications. Future challenges on (AgNP) synthesis, their release into the environment, and scaling up production, as presented in the review, suggest that several potential topics for future works are available to promote a safer and more efficient use of these nanoparticles. Studies on AgNPs in Malaysia have increased since the Malaysian government officially established a directorate for nanotechnology development. This calls for a proper set of policies on AgNPs starting from their production to utilization as well as their effects on various related industries and the environment. [ABSTRACT FROM AUTHOR]