The removal of acetaminophen (AAP) in aqueous solution by the UV/chlorine process was evaluated. The effect of chlorine dose, the initial AAP concentration, pH value, and UV intensity on the reaction were also investigated. The degradation mechanism and the ecological risk were further discussed. The results indicated that AAP degradation fitted pseudo-first-order kinetics. Compared with UV alone or dark chlorination, the combination of UV and chlorine significantly accelerated the degradation process. The AAP degradation was positively affected by chlorine dose and UV intensity, while negatively affected by the initial AAP concentration and ammonia nitrogen concentration during the UV/chlorine process. The frontier orbital theory analysis shows that the C5 position in the benzene ring of AAP is likely to be the first site attacked by HO• and Cl• radical to form the products. Twelve intermediates were identified by Q-TOF and GC-MS. The possible degradation pathways were also proposed. Luminescent bacteria experiment and ECOSAR prediction both revealed that acute toxicity of AAP degradation could only be partially reduced. Ecological risks during the UV/chlorine process need to be further evaluated.

In this study, thermochemical degradation of furfural by sulfate radical has been investigated to find the best-operating conditions. For this purpose, the response surface methodology (RSM) based on central composite design (CCD) was applied to optimize the five independent variables of thermally activated persulfate (TAP)/nZVI oxidation process including pH, PS concentration, furfural concentration, nZVI dosage, and heat. The ANOVA results (“P > F value” < 0.0001 and [Formula: see text] = 0.9701) showed the obtained quadratic model is acceptable to predict furfural removal. Based on the reduced quadratic model PS concentration, nZVI dosage, and heat revealed the positive effects on removal efficiency, while pH and furfural concentration had a negative effect. Accordingly, 98.4% of furfural could be removed within 60 min of reaction under the optimum conditions: pH 5.26, PS concentration of 20.52 mM, furfural concentration of 84.32 mg/L, nZVI dosage of 1.15 mg/L, and a temperature of 79 °C. In such circumstances, the furfural removal efficiency for TAP, PS/nZVI, PS, and nZVI was 94.5, 9, 3, and 2%, respectively. Therefore, based on the synergy index (SI) values, the combination of PS, nZVI, and heat can lead to a synergistic effect in the performance of the thermochemical process.

Remediation of heavy metal–contaminated soils is essential for safe agricultural or urban land use, and phytoremediation is among the most effective methods. The success of phytoremediation relies on the size of the plant biomass and bioavailability of the metal for plant uptake. This research was carried out to determine the effect of Ethylenediaminetetraacetic acid (EDTA) ligand and Cu-resistant plant growth-promoting rhizobacteria (PGPR) on phytoremediation efficiency of selected plants as well as fractionation and bioavailability of copper (Cu) in a contaminated soil. The test conditions included three plant species (maize: Zea mays L., sunflower: Helianthus annuus L., and pumpkin: Cucurbita pepo L.) and six treatments, comprising two PGPR strains (Pseudomonas cedrina K4 and Stenotrophomonas sp. A22), two PGPR strains with EDTA, EDTA, and control (without PGPR and EDTA). The combination of EDTA and PGPR enhanced the Cu concentration in both shoot and root tissues and increased the plant biomass. The Cu specific uptake was at a maximum level in the shoots of pumpkin plants when treated with the PGPR strain K4 + EDTA (202 μg pot⁻¹), and the minimum amount of Cu was recorded for sunflower with no PGPR or EDTA addition (29.6 μg pot⁻¹). The result of the PGPR-EDTA treatments showed that the combined application of EDTA and PGPR increased the shoot Cu-specific uptake approximately fourfold in pumpkin. Pumpkin with the highest shoot Cu specific uptake and maize with the highest root Cu specific uptake were the most effective plants in phytoextraction and phytostabilization, respectively. The effectiveness of different PGPR-EDTA treatments in increasing Cu specific uptake by crop plants was assessed by measuring the amount of Cu extracted from the rhizosphere soil adhering to the roots of crop species, by the use of the single extractants Diethylenetriamine pentaacetic acid (DTPA), H₂O, NH₄NO₃, and NH₄OAc. PGPR-EDTA treatments increased the amount of water-extractable Cu from rhizosphere soils more than ten times that of the control. The combined application of the EDTA and PGPR reduced the carbonated Fe and Mn oxide–bound Cu in the contaminated soil, and increased the soluble and exchangeable concentration of Cu. Pumpkin, with high shoot biomass and the highest shoot Cu specific uptake was found to be the most effective field crop in phytoextraction of Cu from the contaminated soil. The results of this pot study demonstrated that the EDTA+PGPR treatment could play an important role in increasing the Cu bioavailability and specific uptake by plants, and thus increasing the phytoremediation efficiency of plants in Cu-contaminated areas.

Polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants. Exposure to PAHs is associated with several adverse health outcomes. However, no previous study has examined the relationship between PAH exposure and functional dependence in an elderly population. Our aim was to examine whether PAH exposure was associated with functional dependence including total disability, activities of daily living (ADL), instrumental activities of daily living (IADL), leisure and social activities (LSA), lower extremity mobility (LEM), and general physical activities (GPA) in an elderly population. A total of 5816 elderly adults from the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2006 were examined. PAH exposure was measured by urinary biomarkers. Functional dependence was assessed by 19 structured questions. The association between PAH exposures with functional dependence was performed by using a multivariable linear regression model. After adjusting for pertinent variables, positive associations were observed between the total number of disabilities and 2-naphthalene and 1-pyrene quartiles (all Pₜᵣₑₙd < 0.05). There was a dose-dependent relationship between 1-pyrene quartiles and all functional dependence domains, and the higher quartile of 1-pyrene was more closely associated with functional impairment (all Pₜᵣₑₙd < 0.05). PAH exposure is associated with functional dependence in American elderly adults. Future research is needed to bring to light the pathophysiological underlying mechanisms related to these findings.

Daphniopsis tibetana Sars lives in elevation, usually with strong solar UV radiation. We speculate that UV may have an effect on the ecology and evolutionary biology of this species. However, the regulatory effect and mechanism of UV on D. tibetana have not been studied previously. Here, our results showed that UVB could act as a positive factor in the relative body lengths, reproductive parameters, and population growth parameters of D. tibetana when UVB radiation is 20–170 mJ cm⁻², compared with the control group. Strikingly, these parameters were highest at 120 mJ cm⁻². To explore the mechanism underlying the UVB irradiation effects, we conducted a transcriptome analysis using the Trinity platform. The results indicated that differentially regulated genes were mostly enriched in lipid transport and lipid localization by Gene Ontology (GO) enrichment analysis of 146 differentially expressed genes (83 upregulated and 63 downregulated). This is the first study of UVB radiation of D. tibetana to reveal genes that may have crucial roles in survival, growth, and reproduction and could be candidates for future functional studies. Additionally, the study could supply a substantial resource for investigating and elucidating lipids that could play important roles in a physiological context.

Waste electric and electronic equipment (WEEE) represents a potential secondary source of valuable materials, whose recovery is a growing business activity worldwide. In low-income countries, recycling is carried out under poorly controlled conditions resulting in severe environmental pollution. High concentrations of both metallic and organic pollutants have been confirmed in air, soil, water, and sediments in countries with informal recycling areas. The release of these contaminants into the environment presents a risk to the health of the exposed population that has been widely acknowledged but still needs to be quantified. The aim of this work was to evaluate the relative risk from inhalation associated with the open burning of different kinds of WEEE. The shrinking core model was applied to estimate the concentration of the metals which would be released into the environment during the incineration of different types of WEEE. In addition, the potential generation of dioxins during the same informal practice was estimated, based on the plastic content of the WEEE. The results provided for the first time a comparative analysis of the risk posed from the open burning of WEEE components, proposing a methodology to address the absolute risk assessment to workers from the informal recycling of WEEE.

The present work is aimed to analyze the performance and emission characteristics of mahua biodiesel-fueled diesel engine with copper oxide nanoparticle at various particle sizes (10 and 20 nm) and the results compared with conventional diesel fuel (BD). Experiments were conducted in a four-stroke, single-cylinder, constant speed, and naturally aspirated research diesel engine with an eddy current dynamometer. Conventional transesterification process is carried out to convert the raw mahua oil into mahua oil biodiesel (BD100). Copper oxide (CuO) was chosen as a nanoparticle; the mass fraction of 100 ppm and the particle sizes of 10 and 20 nm were blended with mahua oil methyl ester using an ultrasonicator, and the physicochemical properties were measured. The physicochemical properties of BD100 and nanoparticle-included BD100 are at par with EN14214 limits. Brake-specific fuel consumption (BSFC) of BD100 is higher than that of diesel, and brake thermal efficiency (BTE) is lower than that of diesel (D100). The inclusion of 10-nm particle size of CuO nanoparticle in BD100 improves the BSFC and BTE by 1.3 and 0.7%, respectively, when compared with BD100. The CuO nanoparticle inclusion at 20-nm nanoparticle in biodiesel further improves the performance parameters than those at 10-nm nanoparticle. Further, the BD100 promotes a lower level of smoke emissions, carbon monoxide (CO), and hydrocarbon (HC) and with a prominent increase in oxides of nitrogen (NOₓ) emissions. The inclusion of 10-nm particle size of CuO nanoparticle in BD100 reduces the NOₓ, HC, CO, and smoke emission by 3.9, 5.6, 4.9, and 2.8%, respectively, at peak load condition when compared with BD100. The addition of CuO nanoparticle at 20-nm nanoparticle in biodiesel further reduces the NOₓ, HC, CO, and smoke emissions.

The developing world in general is facing so many crucial problems including global warming in recent years. Global warming has multiple consequences on each segment of the society and therefore, its root causes are important to identify. The present study examines the impact of per capita income, trade openness, urbanization, and energy consumption on CO₂ emissions. Countries located in South Asian Association for Regional Cooperation (SAARC) are considered in the study. The selection of the SAARC region is motivated by the diverse nature of its members and further lack of available empirical literature on the same relationship. Annual data from 1980 to 2016 are analyzed using appropriate panel data techniques. The results revealed the presence of environmental Kuznets curve (EKC) in the SAARC region. Further, the introduction of cubic function into the model indicated that the shape of the EKC is N shaped. Besides, trade openness has negative while urbanization and energy consumption have impacted CO₂ emissions positively. Moreover, the causality exercise explored a bidirectional causality between urbanization, energy consumption, per capita income, and CO₂ emissions. Similarly, energy consumption, per capita GDP, and urbanization are also bidirectionally related. Further, a unidirectional causality running from CO₂ emissions, urbanization, and energy consumption to trade openness is detected. Lastly, a unidirectional causality is witnessed from per capita income to energy consumption.

There is a growing trend to implement biosecurity measures in small commercial broiler flocks and trying to replace ineffective antimicrobial with alternative materials to interevent a strategy for the control of Campylobacter bacteria in these farms. This study was designed to determine the prevalence rate of Campylobacter spp. in broiler flocks and their environment. Thereafter, assess the efficiency of chitosan, zinc oxide nanoparticles (ZnO NPs), and chitosan/ZnO NPs composite against Campylobacter strains to adopt a novel control strategy based on the ability to use those nanocomposites. A total of 220 samples were collected from broiler flocks, their environment, and farm attendants that direct contact with birds. All samples were subjected to microbiological investigation for isolation, then molecular identification of bacteria using PCR. ZnO NPs and chitosan/ZnO NPs composite were synthesized then characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectrum (FT-IR), and X-ray diffraction (X-RD). The efficiency of testing compounds was examined against 30 strains of Campylobacter coli (C. coli) to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The highest percentages of C. coli were isolated from the manure storage area, and broiler litter followed by flies, and feeders (66.7, 53.3, 40.0, and 33.3%, respectively). Both chitosan/ZnO NPs and ZnO NPs at a concentration of 0.5 μg/mL and 1.5 μg/mL, respectively showed complete efficiency (100%) against C. coli compared with chitosan compound. In conclusion, manure storage area and broiler litter represented the main reservoir of Campylobacter bacterial contaminant followed by flies in broiler poultry farms. Chitosan/ZnO NPs composite can be used in any biosecurity program of poultry farms as an alternative to ineffective antimicrobial agents.