Anaerobic degradation of xenobiotic organic contaminants (XOCs): The role of electron flow and potential enhancing strategies

Eliminating xenobiotics organic compounds from greywater through green synthetic nanoparticles

Xenobiotic Organic Compounds (XOCs) have been widely considered to be pollutant compounds due to their harmful impacts on aquatic life. However, there have been few rigorous studies of cutting-edge technology used to eradicate XOCs and their presence in bathroom greywater. The present review provides a comprehensive examination of current methodologies used for removing XOCs by photocatalysis of green nanoparticles. It was appeared that zinc oxide nanoparticles (ZnO NPs) have high efficiency (99%) in photocatalysis process. Green synthesis provides proven processes that do not require dangerous chemicals or expensive equipment, making photocatalysis a potential solution for the status quo. XOCs residue was decomposed, and pollutants were eliminated with varied degrees of efficiency using green synthesis ZnO nanoparticles. It is hypothesized that the utilization of photocatalysis can create a greywater treatment system capable of degrading the toxic XOCs in greywater while increasing the pace of production. Hence, this review will be beneficial in improving greywater quality and photocatalysis using green nanoparticles can be an immediate platform in solving the issue regarding the existence of XOCs in greywater in Malaysia. Researchers in the future may benefit from focusing on optimizing photocatalytic degradation using green-synthesis ZnO. It might also help with the creativity and productivity of the next generation of authoritative concerns, notably water conservation.

Highly hazardous pesticides and related pollutants: Toxicological, regulatory, and analytical aspects

The pervasive manifestation and toxicological influence of hazardous pesticides pose adverse consequences on various environmental matrices and humans, directly via bioaccumulation or indirectly through the food chain. Due to pesticide residues' continuous presence above permissible levels in multiple forms, much attention has been given to re-evaluating to regulate their usage practices without harming or affecting the environment. However, there are regulations in place banning the use of multiple hazardous pesticides in the environment. Thus, efforts must be made to achieve robust detection and complete mitigation of pesticides, possibly through a combination of new and conventional methods. The complex nature of pesticides helps them to react differently across different environmental matrices. Therefore, highly hazardous pesticides are a risk to human well-being and the environment through enzymatic inhibition and the induction of oxidative stress. Consequently, developing fast, sensitive sensing strategies is essential to detect and quantify multiple pesticides and remove the pesticides present in the specific matrix without creating harmful derivatives. Additionally, the technology should be available worldwide to eliminate pesticide residuals from the environment. There are regulations, in practice, that limit the selling, storage, use of pesticides, and their concentration in the environment, although such regulations must be revised. However, the existing literature lacks regulatory, analytical detection, and mitigation considerations for pesticide remediation. Furthermore, the enforcement of such regulations and strict monitoring of pesticides in developing countries are needed. This review spotlights various analytical detection, regulatory, and mitigation considerations for efficiently removing hazardous pesticides.

Elucidating degradation properties, microbial community, and mechanism of microplastics in sewage sludge under different terminal electron acceptors conditions

This study is designed to investigate the roles of five key terminal electron acceptors (TEAs): O₂, NO₃^-, Fe³⁺, SO₄^2-, and CH₂O, typically existing in the sludge on the degradation rates and pathways of three representative MPs: polylactic acid (PLA), polyvinyl chloride (PVC), and polyhydroxyalkanoate (PHA). The results revealed that approximately 51.46 ∼ 52.70% of PHA was degraded within 43 days, despite PLA and PVC being degraded insignificantly. Different TEAs significantly affected the end-products of PHA. The production rate of acetate gradually decreased from 90.48, 42.67, 38.30, and 17.56 to 3.30% when the TEAs were tested with CH₂O, O₂, SO₄^2-, NO₃^- and Fe³⁺, respectively. The main functional bacteria involved in the PHA degradation were hydrolysis bacteria Burkholderiaceae and homo-acetogenic bacteria Clostridiacea, which accounted for 0.83% and 18.91% of the microbes. The current investigation could help improve understanding of MPs degradation pathways and mechanisms and minimize their risks in practice.