Search

In the race for economic development and prosperity, our earth is becoming more polluted with each passing day. Technological advances in agriculture and rapid industrialization have drastically polluted the two pillars of natural resources, land and water. Toxic chemicals and microbial contaminants/agents created by natural and anthropogenic activities are rapidly becoming environmental hazards (EH) with increased potential to affect the natural environment and human health. This review has attempted to describe the various agents (chemical, biological, and physical) responsible for environmental contamination, remediation methods, and risk assessment techniques (RA). The main focus is on finding ways to mitigate the harmful effects of EHs through the simultaneous application of remediation methods and RA for sustainable development. It is recommended to apply the combination of different remediation methods using RA techniques to promote recycling and reuse of different resources for sustainable development. The report advocates for the development of site-specific, farmer-driven, sequential, and plant-based remediation strategies along with policy support for effective decontamination. This review also focuses on the fact that the lack of knowledge about environmental health is directly related to public health risks and, therefore, focuses on promoting awareness of effective ways to reduce anthropological burden and pollution and on providing valuable data that can be used in environmental monitoring assessments and lead to sustainable development., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

In several low- and middle-income countries, such as India, the rapid construction of toilets to combat open defecation has not been matched with adequate wastewater treatment, resulting in extreme fecal contamination of the receiving environments. The sewage-receiving surface water bodies, typically close to the residences, are a potential hotspot for disease transmission and antibiotic resistance. Water, soil, and sediment samples from seven wastewater-receiving ponds (WRPs) were analyzed for water quality, chlorophyll-a, fecal contamination (yccT for Escherichia coli), 16S rRNA gene copies, and anthropogenic antibiotic resistance gene markers-sul1 and intI1. These WRPs were contrasted with two ponds that did not directly receive sewage. The water quality in the WRPs was comparable to raw sewage (BOD: 210-380 mg/L; COD: 350-630 mg/L; total-N: 100-190 mg/L; and total-P: 6-21 mg/L), and the relative levels of the DNA marker of E. coli were very high (yccT: 0.1% to ∼100% of total bacterial count) indicating extreme fecal contamination. The relative levels of sul1 and intI1 were 1-3 orders of magnitude higher in WRPs (sul1: 0.32%-10% of total bacterial count; and intI1: 0.2%-5% of total bacterial count) compared to the ponds that did not receive sewage directly. The relative levels of sul1 correlated with the DNA marker for the fecal indicator, E. coli (p-value < 0.05; r = 0.50; Spearman's rank correlation), and poor water quality., (© 2023 The Authors. Journal of Environmental Quality © 2023 American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Agro-waste having lignocellulosic biomass is considered most effective (heating value 16 MJ/kg) for energy production through anaerobic digestion (AD). However, recalcitrant lignocellulosic fraction in agro-waste obstructs its biotransformation and is a rate-limiting step of the process. This study investigated the effects of hydrothermal and thermal-alkaline pretreatment on anaerobic co-digestion of wheat straw (WS). The hydrothermal pretreatment of WS revealed that 60 min was the best pretreatment time to achieve the highest substrate solubilization. It was employed for thermal-alkali pretreatment at variable temperatures and NaOH doses. Thermal-alkali pretreatment at 125°C-7% NaOH shows the highest (34%) biogas yield of 662 mL/gVS, followed by 646 mL/gVS biogas yield at 150°C-1% NaOH assay (31% higher) over control. Although the 125°C-7% NaOH assay achieved the highest biogas yield, the 150°C-1% NaOH assay was found more feasible considering the cost of a 6% higher chemical used in the earlier assay. The thermal-alkali pretreatment was observed to reduce the formation of recalcitrant compounds (HMF, Furfural) and increase the buffering capacity of the slurry over hydrothermal pretreatment. Principal component analysis (PCA) of the various pretreatment and AD operational parameters was carried out to study their in-depth correlation. Moreover, a kinetic study of the experimental data was performed to observe the biodegradation trend and compare it with the Modified Gompertz (MG) and First Order (FO) models., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)