The co-contamination of farmland soils with heavy metals and antibiotics from the application of livestock and poultry manures poses great threats to human health. Phytoremediation might be a good solution to this problem. A pot culture experiment was conducted to evaluate the remediation capacity of two ornamental hyperaccumulators, namely, Mirabilis jalapa L. and Tagetes patula L., in alkaline soils co-contaminated with cadmium (Cd) and tetracycline antibiotics (TCs). The growth of M. jalapa and T. patula was significantly influenced by the co-contaminated soil. In treatments with TCs alone, the growth of T. patula was promoted (p < 0.05), while that of M. jalapa was inhibited. In the C2T3 treatment with TCs and Cd combined, the biomass of T. patula and M. jalapa decreased by 42.27% and 56.15% in roots and by 22.24% and 32.27% for in shoots, respectively, compared with those in the same treatment without TCs. The addition of TCs increased the accumulation of Cd in treatments with less than 15.0 mg/kg Cd. In M. jalapa, the concentration of Cd increased by 4.64% and 39.69% in roots and by 30.33% and 71.71% in shoots, and that in T. patula increased by 74.66% and 11.03% in roots and by 15.36% and 17.58% in shoots, respectively, in two treatments with TCs compared with those in the treatments with Cd alone. However, the accumulated Cd amounts decreased from 36.25 to 31.91 μg/pot and increased from 201.33 to 229.26 μg/pot in C2T2 for M. jalapa and T. patula, respectively, compared with those in the treatments without TCs. The TC removal efficiencies of all treatments were above 99%, and the residual amounts of TC and OTC were higher than that of CTC. M. jalapa and T. patula are promising hyperaccumulators that can be used for the remediation of alkaline soil co-contaminated with Cd and TCs.

Due to the wonderful property of hydrogels, they can provide a platform for a wide range of applications. Recently, there is a growing research interest in the development of potential hydrogel adsorbents in wastewater treatment due to their adsorption ability toward aqueous pollutants. It is important to prepare such a hydrogel that possesses appropriate robustness, adsorption capacity, and adsorption efficiency to meet the need of water treatment. In order to improve the property of hydrogels, much effort has been made by researchers to modify hydrogels, among which incorporating inorganic components into the polymeric networks is the most common method, which can reduce the product cost and simplify the preparation procedure. Not only can hydrogel be applied as adsorbent, but it also can be used as matrix for catalyst immobilization. In this review, the key advancement on the preparation and modification of hydrogels is discussed, with special emphasis on the introduction of inorganic materials into polymeric networks and consequential changes in the properties of mechanical strength, swelling, and adsorption. Besides, hydrogels used as adsorbents for removal of dyes and inorganic pollutants have been widely explored, but their use for adsorbing emerging contaminants from aqueous solution has not received much attention. Thus, this review is mainly focused on hydrogels’ application in removing emerging contaminants by adsorption. Furthermore, hydrogels can be also applied in immobilizing catalysts, such as enzyme and photocatalyst, to remove pollutants completely and avoid secondary pollution, so their progress as catalyst matrix is overviewed.

(Ce,Zr,La)O₂ (CZL) mixed oxide-supported rhodium (Rh) catalysts were prepared by in situ synthesis method. Characterizations were adopted to investigate the relation of structure and metal-support interaction with catalytic behavior of catalysts. The results demonstrate that appropriate Ce/Zr ratio (2/1~1/4) could help to form more homogenous CZL ternary solid solution and promote the formation of more oxygen vacancies and defects (the lattice defects resulting from lattice distortion) in CZL supports, and thereby enhance oxygen storage/release performance. Meanwhile, it strongly affects the interaction between RhOₓ and CZL supports, which promotes the formation of more active Rh species (Rh⁰ + Rh³⁺) and the reduction of the oxygen species in Rh–Ce interface, leading to the enhancement of catalytic performance for HC, CO, and NOₓ eliminations. Rh/CZL-12 shows the best catalytic activity for HC and NOₓ eliminations. It could be attributed to the enhanced activation and oxygen mobility of lattice oxygen, which is verified by the results of DOSC measurement.

Zinc is one of the important essential trace minerals to human health due to its antioxidant properties. The present study was conducted to elucidate its potential protective role against maneb-induced nephrotoxicity. For this purpose, animals were randomly divided into four groups of six each. Mice of group I (negative controls) have received daily 0.5 ml of distilled water, a solvent of maneb. Mice of group II (MB) have received 30 mg/kg bw of maneb daily by intraperitoneal way. Mice of group III (MB + Zn) have received the same dose of maneb as group II, along with ZnSO₄ (30 mg/kg bw) daily. Mice of group IV (Zn), considered as positive controls, have received the same dose of ZnSO₄ as group III daily. Our results revealed that ZnSO₄ co-administration to maneb-treated mice decreased kidney levels of malondialdehyde, hydrogen peroxide, protein carbonyls, and advanced oxidation protein products; the levels of non-enzymatic antioxidants like vitamin C, glutathione, and metallothionein. It recovered the alteration of antioxidant enzyme activities (catalase, superoxide dismutase, and glutathione peroxidase) and attenuated DNA fragmentation. Furthermore, this essential trace element was also able to alleviate kidney biomarkers’ alterations by lowering plasma levels of creatinine, urea, uric acid, and lactate dehydrogenase. In addition, the histopathological changes induced by maneb were improved following zinc administration. Our results indicated that zinc might be beneficial against maneb-induced renal oxidative damage in mice.

The undesirable effects of silver nanoparticles (AgNPs) on soil environment have caused much concern. The previous studies, however, focused on sandy soil, with little known on others. In present study, the effects of polyvinylpyrrolidone-coated AgNPs (0, 1, 10, and 100 mg kg⁻ ¹ soil) on enzyme activities (urease and dehydrogenase), ammonia-oxidizing bacteria (AOB) and archaea (AOA), bacterial and archaeal communities, and microbial function profile in a yellow-brown loam soil were investigated. The significant dose-response inhibitions of AgNPs on enzyme activities were observed, with dehydrogenase more susceptible to AgNPs. Both of bacterial and archaeal amoA genes were reduced by AgNPs above 10 mg kg⁻ ¹, with AOB more susceptible to AgNPs than AOA. AgNPs at 100 mg kg⁻ ¹ caused reductions on the dominant Nitrosospira and Nitrosomonas, and even disappearance on Nitrosovibrio, while increase on Nitrososphaera significantly. AgNPs also changed bacterial and archaeal community structure. Exposure to AgNPs at 100 mg kg⁻ ¹ caused significant increases by 186.79% and 44.89% for Bacteroidetes and Proteobacteria, while decreases by 47.82%, 44.09%, 43.67%, and 80.44% for Actinobacteria, Chloroflexi, Planctomycetes, and Verrucomicrobia, respectively. Moreover, three dominant archaeal phyla (Thaumarchaeota, Euryarchaeota, and Parvarchaeota) were also reduced in the presence of AgNPs, especially Thaumarchaeota with the significant reduction of 13.71%. PICRUSt prediction revealed that AgNPs indeed had the potential to change soil microbial community’s functional contributions. It must be cautious on the interference of AgNPs to soil ecological functions in the future.

The present study aimed to investigate the concentration of highly toxic heavy metal, lead (Pb), in cows and buffaloes of Sargodha district, Punjab, Pakistan. Samples of three major organs (spleen, lungs, bones) from five localities were obtained from two age groups (< 2 years, > 2 years) of each animal. With the confidence level of 95%, the investigated results demonstrated that lead concentration ranged from 0.28 to 1.12 mg kg⁻¹ and 0.31 to 0.83 mg kg⁻¹ in cows and buffaloes respectively. Out of the three tested organs, spleen contained the highest level of Pb (0.64–0.83 mg/kg) followed by lungs (0.28–1.12 mg/kg) and bones (0.36–0.87 mg/kg). Furthermore, a significant increase of Pb was observed in older animals. It was demonstrated that both age groups had Pb accumulation higher than the standard limit of 0.1 mg kg⁻¹. Serving as bioindicators, the presence of toxic levels of lead in the animals indicated environmental pollution and possible risks for public health. High lead concentration in dietary commodities from Sargodha district calls for the sound management of hazardous waste. High levels of this toxic metal also indicate the possible health risks to human population of the areas in Sargodha. It is highly needed to address this metal contamination and its probable entry route into the food chain of the domesticated animals. This must be further investigated to prevent animals from lead exposure.

This study explores the interaction among coal consumption, pollutant emissions, and real income for South Africa in a multivariate setting. To achieve this objective, annual frequency data spanning from 1965 to 2017 is used for analysis. A series of econometrics tests were conducted ranging from stationarity and non-stationarity tests for unit root properties of the variables under consideration. Empirical evidence finds support for the inverted U-shaped pattern between energy consumption and environmental degradation in South Africa. The Toda-Yamamoto Granger causality test shows a feedback causality between economic growth and carbon dioxide emissions, as well as between GDP and coal consumption. All these highlighted findings have inherent environmental implications. Based on these outcomes, policy directions such as diversification of the South Africa energy mix to renewables and cleaner energy sources and also the adoption of carbon capturing and storage techniques were suggested to engender a cleaner and friendlier environment.

Organophosphate esters (OPEs), as a class of emerging flame retardant and plasticizers, have attracted particular attention due to their ubiquitous existence in the environment and potential effects on human health. Here, we investigated the levels of OPEs in human serum and examined the role of demographic variables on the body burden of such compounds. Of 11 OPEs screened, 8 were detected in human serum samples collected from a population (n = 89) in Bohai Bay, North China. The ∑OPE concentrations ranged from 4.7 to 948 ng/g lipid weight (lw), with a median concentration of 243 ng/g lw. Tris(2-chloroethyl)phosphate (TCEP) was identified as the most abundant OPEs with a median concentration of 214 ng/g lw. The concentrations of the triphenyl phosphate (TPhP) in older adults were higher than those in young adults (p < 0.05), and lower concentrations of tri-iso-butyl phosphate (TIBP) were observed in female samples compared to males. Furthermore, significant differences were observed in tri-n-propyl phosphate (TPrP) concentrations between urban and rural residence groups (p < 0.05). This study provides important information on the accumulation potential of OPEs in human bodies and suggests the need for further investigation to understand the potential human health risk.

The remediation of nonaqueous phase liquids (NAPLs) enhanced by surfactant and nanoparticles (NP) has been investigated in numerous studies. However, the role of NP-assisted surfactants in the dissolution process is still not well discussed. Besides, there is a lack of empirical dissolution models considering the effects of initial residual saturation Sₜᵣₐₚ, NAPL distribution, and surfactant concentration in NAPL-aqueous phase systems. In this work, micromodel experiments are conducted to quantify mass transfer coefficients for different injected aqueous phases including deionized water, SDS surfactant solutions, and NP-assisted solutions with different levels of concentrations and flow rates. Observations reveal that silica nanoparticles (SNP) can significantly enhance interphase mass transfer, while SDS surfactant reduces the mass transfer coefficient. In addition, Sₜᵣₐₚ and intrinsic interfacial area aᵢ, as an indicator of dense nonaqueous phase liquids (DNAPL) distribution, influence the interphase mass transfer. The aᵢ is also independent of DNAPL saturation SNAPL except for SNAPL < 7% when ganglia breakup occurs. Based on these observations, new empirical dissolution models are proposed in the presence and the absence of SDS surfactant and SNP in which aᵢ, Sₜᵣₐₚ, and surfactant concentrations are introduced as new parameters. The evaluated mass transfer rate coefficients using the proposed models show a significant improvement compared to available empirical models. The finding of this study might be attractive for application in field-scale simulations of surfactant-enhanced aquifer remediation (SEAR) and NP-assisted methods.

Triclosan (TCS), an antimicrobial agent, has been a pollutant of increasing concern owing to its potential health risk on humans and aquatic animals. The present study seeks to test the hypothesis that TCS could alter the oxidative stress-related parameters in the brain and liver, as well as eliciting DNA damage in hepatocytes of adult zebrafish. On the basis of the 96 h LC₅₀ (398.9 μg/L), adult zebrafish were separately exposed to 50, 100, and 150 μg/L TCS for 30 days. The brain and liver tissues from adult zebrafish were excised and assayed for a suite of antioxidant parameters and oxidative stress biomarkers including DNA damage in the liver. The induced effect by TCS on the activity of acetylcholinesterase (AChE) was also analyzed in the brain. Results showed a significant decrease in superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in the brain and liver of adult zebrafish. Also, the contents of the glutathione system (GSH and GSSH), as well as the activity of the glutathione reductase (GR), assayed in the liver, were reduced while the contents of malondialdehyde (MDA) were elevated in the liver. A comet assay revealed dose-dependent DNA damage in zebrafish hepatocytes. The 8-hydroxy-2′-deoxyguanosine (8-OHdG), MDA, and carbonyl protein contents in brain tissues significantly increased. Moreover, the AChE in the zebrafish brain was induced. Apparently, no obvious histological changes in brain tissues of zebrafish were observed compared with those of the control whereas atrophy and necrosis of hepatocytes and increased hepatic plate gap were observed in zebrafish hepatocytes after TCS exposure. The obtained results highlight that sublethal concentrations of TCS may be deleterious to the liver and brain of adult zebrafish upon subchronic exposure.