This study investigated the efficacy of electrokinetic remediation of soils polluted with different concentrations of tetracyclines (TCs). Three widely used TCs (oxytetracycline, chlortetracycline, and tetracycline) were selected, and concentrations of 0, 5, 10, 20, and 50 mg/kg (C0, C5, C10, C20, C50) were selected for comparison. Antibiotic-polluted soils with no electric field served as controls. The average removal rates of TCs in different treatments ranged from 25 to 48% after 7-day remediation. The contributing ratios of electrokinetics to TCs removal varied from 22 to 84%. The concentrations of NH₄⁺ increased in soils and electrolytes, which indicated the decomposition of TCs in the electric field. The highest removal amount of TCs was obtained in the C50 treatment, due to efficient reactions of TCs with oxidative radicals generated during the electrolysis. The fluctuant range of pH in the electrolytes was decreased with increasing concentration of TCs, while the soil pH was increased. The removal rate of antibiotic-resistant bacteria (ARB) in the C5 treatment was significantly higher than that in other treatments. The abundance of antibiotic resistance genes (ARGs) increased with the concentrations of TCs in soils. It might result from the induction of increasing selective pressure of antibiotics. Significant removal of ARGs occurred in the C50 treatment (38–60%). In terms of controlling ARB and ARGs, which were more resistant, the electrokinetic technology showed advantageous effects. Above all, electrokinetic technology provides an effective remediation method, especially for TC-polluted soil with a concentration of 20–50 mg/kg.

The composite photocatalyst of precious metal loaded on BiOI (M/BiOI, M = Pt, Au, Ag) was prepared by photochemical deposition and used for the photocatalytic degradation of microcystins (MC-LR). The material was characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet visible (UV-vis) diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy (XPS), and photoluminescence spectra (PL). The effect of photodegradation of MC-LR and the possible mechanism were investigated. It turned out that, among precious metals of Pt, Au, and Ag, Ag had the most significant improvement for photocatalytic activity of BiOI and Au was the least. The Ag/BiOI catalyst was illuminated 2 h under the simulated visible-light condition with the optimal load ratio of Ag catalyst (1.0 wt%) and the 2-h illumination under simulated visible-light condition, the degradation rate of MC-LR was 61.26% ± 0.12%. In addition, through the experiment of trapping agent and the analysis of electron spin resonance (ESR), we could conclude that the main active species is O₂⁻ in the process of the degradation of MC-LR by three precious metal-loaded BiOI semiconductor materials.

Arsenic (As) is often found naturally as the co-contaminant in the uranium (U)-contaminated area, obstructing the bioremediation process. Although the U-contaminated environment harbors microorganisms capable of interacting with U which could be exploited in bioremediation. However, they might be unable to perform with their full potential due to As toxicity. Therefore, potential in arsenic resistance and oxidation is greatly desired among the microorganisms for a continued bioremediation process. In this study, arsenic-resistant bacteria were isolated from U ore collected from Bundugurang U mine, characterized and their As oxidation and U removal potentials were determined. 16S rRNA gene sequencing and phylogenetic analysis showed the affiliation of isolated bacteria with Microbacterium, Micrococcus, Shinella, and Bacillus. Except Bacillus sp. EIKU7, Microbacterium sp. EIKU5, Shinella sp. EIKU6, and Micrococcus sp. EIKU8 were found to resist more than 400 mM As(V); however, all the isolates could survive in 8 mM As(III). The isolates were found to readily oxidize As under different culture conditions and are also resistant towards Cd, Cr, Co, Ni, and Zn. All the isolates could remove more than 350 mg U/g dry cells within 48 h which were found to be highly dependent upon the concentration of U, biomass added initially, and on the time of exposure. Ability of the isolates to grow in nitrogen-free medium indicated that they can flourish in the nutrition deprived environment. Therefore, the recovery of isolates with the potent ability to resist and oxidize As from U ore might play an important role in toxic metal bioremediation including U.

Hydroxyurea (HDU), a class of antineoplastic drugs, has a powerful efficacy in the treatment of several types of malignancies. However, it has multiple adverse effects including reduced fertility, especially in males. Thus, 60 male albino rats were used to investigate the chemoprotective potentials of royal jelly on HDU-induced testicular damage. Animals were gastro-gavaged with HDU (225 or 450 mg kg⁻¹ bw day⁻¹) before royal jelly (100 mg kg⁻¹ bw day⁻¹) for 60 days. Blood samples and testicles were collected, and spermatozoon was obtained. In a dose-dependent manner, the sperm count, motility and liveability, and testosterone, GSH, and catalase concentrations were decreased in HDU groups, whereas MDA, FSH, LH, IL-6, and IFN-γ expression levels were increased. Germinal epithelium degeneration, germ cell sloughing, reduction in the number of luminal spermatozoa, interstitial congestion, and severe leukocyte infiltration besides no glandular secretion in most of the acini were identified. However, royal jelly intake in HDU-treated rats successfully improved sperm quality, hormonal and antioxidant status, and reproductive organ histoarchitecture. Thus, it could be concluded that royal jelly is endowed with antioxidative and anti-inflammatory activities and could be, therefore, used as an adjuvant remedy to improve HDU-induced male subfertility.

A combined use of silver nanoparticles (AgNPs) with different types of disinfectants as antimicrobial might be useful in mitigating the problem of development of bacterial resistance with a strong enhancement of the biocidal effect of disinfectants. To evaluate the biocidal activity of silver nanoparticles and its loaded forms, five commercial disinfectants (quaternary ammonium compounds (benzalkonium chloride (BC) and TH⁴⁺), Virkon®S, sodium hypochlorite, and hydrogen peroxide (H₂O₂)) were used against Listeria monocytogenes (L. monocytogenes) isolates at different concentrations and exposure times to reveal intra-species variability and the percentage of resistance to antimicrobial agents used. Therefore, a total of 260 specimens from animal and human stool as well as environmental samples from dairy cattle farms were cultured for isolation of L. monocytogenes. Thereafter, bacterial isolates were identified using PCR. Silver nanoparticle was synthesized using chemical reduction. Both silver nanoparticles and its loaded forms were characterized by transmission electron microscopy (TEM). The sensitivity test of 60 strains of L. monocytogenes bacteria to AgNPs and its loaded forms was evaluated using broth macrodilution method. Virkon®S/AgNPs 2.0% exhibited the highest bactericidal effect (100%) against L. monocytogenes strains followed by H₂O₂/AgNPs 5.0% and TH⁴⁺/AgNPs 1.0% (90% each). Furthermore, the percentage of resistance of L. monocytogenes was 0.0% to both H₂O₂/AgNPs 5.0% and Virkon®S/AgNPs 2.0%. In conclusion, monitoring the main source of contamination with Listeria monocytogenes in dairy cattle farms is an essential factor to achieve an efficient control. Moreover, the use of the disinfectants, Virkon®S 2.0%, H₂O₂ 5.0%, and TH⁴⁺1.0%, loaded on silver nanoparticles composite had the strong bactericidal effect against L. monocytogenes.

The deammonification process is a promising technology, while achieving stable performance is still a challenge for domestic sewage treatment. To investigate the stability of deammonification in the plug flow system, which can be updated from A/O or A/A/O bioreactor, a plug flow fixed biofilm reactor was started-up and fed with synthetic low-strength wastewater. As a result, average ammonium removal efficiency of 90.0 ± 10.0% and total nitrogen removal efficiency of 79.4 ± 9.3% were achieved, while the nitrate production ratio (∆Nitrate/∆Ammonium) was at superior levels (9.5 ± 3.4%). Candidatus Jettenia and Candidatus Brocadia were the anammox bacteria in this reactor, and Candidatus Jettenia was the predominant anammox bacteria. Anammox bacteria were dominated in three of the four sampling points except the first one. Relative abundance of NOB increased along the reactor. The result of the present work implied that the plug flow system was able to maintain stable deammonification process, and NOB was suppressed by higher residual ammonium concentration in the front of reactor while the suppression weakened along the reactor.

In this work, biochar (BC), activated carbon (AC), and graphene oxide (GO) were thiol-functionalized using 3-mercaptopropyltrimethoxysilane (3-MPTS) (named as BCS, ACS, and GOS, respectively). BCS, ACS, and GOS were synthesized mainly via the interaction between hydrolyzed 3-MPTS and surface oxygen-containing functional groups (e.g., –OH, O–C=O, and C=O) and π-π interaction. The materials before and after modification were characterized and tested for mercury removal, including sorption kinetics and isotherms, the effects of adsorbent dosage, initial pH, and ionic strength. Pseudo-second-order sorption kinetic model (R² = 0.992~1.000) and Langmuir sorption isotherm model (R² = 0.964~0.998) fitted well with the sorption data of mercury. GOS had the most –SH groups with the largest adsorption capacity for Hg²⁺ and CH₃Hg⁺ (449.6 and 127.5 mg/g), followed by ACS (235.7 and 86.7 mg/g) and BCS (175.6 and 30.3 mg/g), which were much larger than GO (96.7 and 4.9 mg/g), AC (81.1 and 24.6 mg/g), and BC (95.6 and 9.4 mg/g). GOS and ACS showed stable mercury adsorption properties at a wide pH range (2~9) and ionic strength (0.01~0.1 mol/L). Mercury maybe removed by ligand exchange, surface complexation, and electrostatic attraction.

Insect physiology is affected by the presence of toxins in the surrounding environment of insects as well as their food sources. The objective of this study was to determine the effect of heavy metal exposure to two low concentrations (50 μg/g and 150 μg/g) of lead (Pb) and zinc (Zn) through artificial diet to the larvae on biological parameters of Asian armyworm (Spodoptera litura Fabricius) (Lepidoptera: Noctuidae). Both Pb and Zn, even at low concentrations, had relatively high toxic effects on S. litura larvae (P < 0.01). S. litura larval weight and length suffered the maximum reduction when the larvae were fed on diet mixed with the high Pb concentration (150 μg/g) tested compared to the other treatments. At the same Pb concentration (150 μg/g), values of larva growth index, pupa growth index, immature growth index, standardized growth index, and fitness index were 4.66, 7.33, 7.82, 5.35, and 10.00 times lower, respectively, than those of control. At the same Zn concentration (150 μg/g), values of larval growth index, pupal growth index, immature growth index, standardized growth index, and fitness index were 5.61, 3.00, 3.04, 3.23, and 9.24 times lower, respectively, than those of control. The survival rate of S. litura larvae was also lower (12.5%) when the larvae were fed on diet mixed with Pb at 150 μg/g after 10 days of observation. Overall, the presence of those heavy metals in the environment, even at low concentrations, would exert an adverse impact on larvae development of this insect. From this point of view, findings could provide a basis for long-term evaluation of heavy metal risk and its impact on populations of important agricultural pests.

Bisphenol A (BPA) is an endocrine disruptor. To evaluate the effect of canned food consumption on internal BPA dose, urinary BPA concentrations were measured before and after intake of canned foods. This study applied a randomized crossover design, recruited 20 healthy volunteers, and divided them into two groups. One group consumed canned food; the other group consumed fresh food. After a 1-day washout, the dietary interventions were reversed. In each period, urine samples were collected immediately before meals and then 2 h, 4 h, and 6 h after meals. A mixed-effects model was used to assess BPA changes over time. Our results showed urinary BPA concentrations increased after consumption of canned food. Specifically, urinary BPA concentrations significantly differed between consumption of canned food and fresh food at 2 h, 4 h, and 6 h after intake (p values of 0.001, < 0.001, and < 0.001, respectively). Mean BPA concentrations at 2 h, 4 h, and 6 h after meals were 152%, 206%, and 79% higher, respectively, than mean BPA concentrations before meals. Urine concentration profiles of canned food intake showed that peaks were at 4 h, the increase diminished at 6 h, and returned to baseline levels at 24 h after intake. Therefore, dietary intervention and a 1-day washout period are effective for limiting internal BPA burden. This study provides convincing evidence of a human exposure route to BPA and a basis for designing interventions to mitigate exposure.

This study firstly aimed to investigate the potential of simultaneous metal (loid) removal from metal (oid) solution through adsorption on iron-peat, where the sorbent was made from peat and Fe by-products. Up-flow columns filled with the prepared sorbent were used to treat water contaminated with As, Cu, Cr, and Zn. Peat effectively adsorbed Cr, Cu, and Zn, whereas approximately 50% of inlet As was detected in the eluent. Iron-sand was effective only for adsorbing As, but Cr, Cu, and Zn were poorly adsorbed. Only iron-peat showed the simultaneous removal of all tested metal (loid)s. Metal (loid) leaching from the spent sorbent at reducing conditions as means to assess the behaviour of the spent sorbent if landfilled was also evaluated. For this purpose, a standardised batch leaching test and leaching experiment at reducing conditions were conducted using the spent sorbent. It was found that oxidising conditions, which prevailed during the standardised batch leaching test, could have led to an underestimation of redox-sensitive As leaching. Substantially higher amounts of As were leached out from the spent sorbents at reducing atmosphere compared with oxidising one. Furthermore, reducing environment caused As(V) to be reduced into the more-toxic As (III).