Aging is a leading cause of mortality for the elderly and DNA methylation age is reported to be predictive of biological aging. However, few studies have investigated the associations between multiple metals exposure and accelerated aging in the elderly. We performed a pilot study of 288 elderly participants aged 50–115 years and measured genome-wide DNA methylation and 22 blood metals concentrations. Measures of DNA methylation age were estimated using CpGs from Illumina HumanMethylation EPIC BeadChip. Linear mixed regression and Bayesian kernel machine regression (BKMR) models were used to estimate the individual and overall associations between multiple metals and accelerated methylation aging. Single metal models revealed that each 1-standard deviance (SD) increase in log-transformed vanadium, cobalt, nickel, zinc, arsenic, and barium was associated with a −2.256, −1.318, 1.004, −1.926, 1.910 and −1.356 changes in ΔAge, respectively; meanwhile, for aging rate, the change was −0.019, −0.013, 0.010, −0.018, 0.023, and −0.012, respectively (all P < 0.05). The BKMR models showed reverse U-shaped associations of the overall metals mixture with ΔAge and aging rate. Downward trends of ΔAge and aging rate were observed for increasing quantiles of essential metals mixture, but upward trends were observed for non-essential metals mixture. Further individual analysis of the BKMR revealed that the 95% confidence interval of ΔAge and aging rate associated with vanadium, zinc, and arsenic did not cross 0, when other metals concentrations set at 25th, 50th, and 75th percentile. Our findings suggest reverse U-shaped associations of the overall metals mixture with accelerated methylation aging for the first time, and vanadium, zinc, and arsenic may be major contributors driving the associations.

A three-dimensional hydrodynamic-antibiotic model is developed to investigate the transport and dilution of sulfamethoxazole (SMX) in the Upper Gulf of Thailand (UGoT). The simulation produced a spatially averaged annual mean SMX concentration of 0.58 μgm−3, which varied slightly between seasons assuming a temporally constant river SMX loading observed in August. In contrast, the horizontal distribution of SMX concentrations strongly varied with season because of the changing residual currents. In addition, SMX is diluted to concentrations lower than 10% of those in river waters a short distance offshore of the estuaries. To better understand this behavior, we examined the relationship between salinity and SMX concentrations in the UGoT. The annual budget demonstrates that 98% of SMX in the UGoT is removed by natural decomposition. As the concentrations of fluvial pollutants in the UGoT depend on their river loading and decomposition rates, functions were derived to predict pollutant concentrations and flushing times based on the river input flux and half-life.

Due to the unreasonable use and discharge of the aquaculture industry, over standard of the antibiotics has been frequent in different types of water environments, causing adverse effects on aquatic organisms. Lycopene (LYC) is an esculent carotenoid, which is considered to be a strong antioxidant. This study was designed to explore the therapeutic effect of LYC on antibiotic (sulfamethoxazole (SMZ)) induced intestinal injury in grass carp Ctenopharyngodon idella. The 120 carps (the control, LYC, SMZ, and co-administration groups) were treated for 30 days. We found that treatment with LYC significantly suppressed SMZ-induced intestinal epithelial cell damage and tight junction protein destruction through histopathological observation, transmission electron microscopy and detection of related genes (Claudin-1/3/4, Occludin and zonula occludens (ZO)-1/2). Furthermore, LYC mitigated SMZ-induced dysregulation of oxidative stress markers, including elevated malondialdehyde (MDA) levels, and consumed super oxide dimutese (SOD), catalase (CAT) activities and glutathione (GSH) content. In the same treatment, LYC reduced inflammation and apoptosis by a detectable change in pro-inflammatory factors (tumor necrosis factor-alpha (TNF-β), interleukin (IL)-1β, IL-6 and IL-8), anti-inflammatory factors (transforming growth factor-beta (TGF-β) and IL-10) and pro-apoptosis related genes (p53, p53 upregulated modulator of apoptosis (PUMA), Bax/Bcl-2 ratio, caspase-3/9). In addition, activation of autophagy (as indicated by increased autophagy-related genes through AMPK/ATK/MTOR signaling pathway) under the stress of SMZ was also dropped back to the original levels by LYC co-administration. Collectively, our findings identified that LYC can serve as a protectant agent against SMZ-induced intestinal injury.

In this critical review, we explored the most recent advances about the fate of antibiotics on biological wastewater treatment plants (WWTP). Although the occurrence of these pollutants in wastewater and natural streams has been investigated previously, some recent publications still expose the need to improve the detection strategies and the lack of information about their transformation products. The role of the antibiotic properties and the process operating conditions were also analyzed. The pieces of evidence in the literature associate several molecular properties to the antibiotic removal pathway, like hydrophobicity, chemical structure, and electrostatic interactions. Nonetheless, the influence of operating conditions is still unclear, and solid retention time stands out as a key factor. Additionally, the efficiencies and pathways of antibiotic removals on conventional (activated sludge, membrane bioreactor, anaerobic digestion, and nitrogen removal) and emerging bioprocesses (bioelectrochemical systems, fungi, and enzymes) were assessed, and our concern about potential research gaps was raised. The combination of different bioprocess can efficiently mitigate the impacts generated by these pollutants. Thus, to plan and design a process to remove and mineralize antibiotics from wastewater, all aspects must be addressed, the pollutant and process characteristics and how it is the best way to operate it to reduce the impact of antibiotics in the environment.

Biodegradation is responsible for most contaminant removal in plumes of organic compounds and is fastest at the plume fringe where microbial cell numbers and activity are highest. As the plume migrates from the source, groundwater containing the contaminants and planktonic microbial community encounters uncontaminated substrata on which an attached community subsequently develops. While attached microbial communities are important for biodegradation, the time needed for their establishment, their relationship with the planktonic community and the processes controlling their development are not well understood. We compare the dynamics of development of attached microbial communities on sterile substrata in the field and laboratory microcosms, sampled simultaneously at intervals over two years. We show that attached microbial cell numbers increased rapidly and stabilised after similar periods of incubation (∼100 days) in both field and microcosm experiments. These timescales were similar even though variation in the contaminant source evident in the field was absent in microcosm studies, implying that this period was an emergent property of the attached microbial community. 16S rRNA gene sequencing showed that attached and planktonic communities differed markedly, with many attached organisms strongly preferring attachment. Successional processes were evident, both in community diversity indices and from community network analysis. Community development was governed by both deterministic and stochastic processes and was related to the predilection of community members for different lifestyles and the geochemical environment.

Four phenylurea herbicides (PUHs) were assessed for degradation and transformation into N-nitrosodimethylamine (NDMA) under three oxidation conditions (chlorine (Cl₂), chlorine dioxide (ClO₂), and ozone (O₃)) from an aqueous solution. Removal ratios correlated with the numbers of halogen elements contained in PUHs (isoproturon ₍₀₎ > chlorotoluron ₍₁ Cₗ₎ > diuron ₍₂ Cₗ₎ > fluometuron ₍₃ F₎), and the degradation efficiencies of oxidants from fastest to slowest were: O₃, ClO₂, and Cl₂. NDMA can be generated directly from the ozonation of PUHs. Further, compared with chloramination alone, ozonation prominently promoted NDMA formation potential (NDMA-FP) during post-chloramination, and NDMA-FPs increased approximately 23–68 times than those during ozonation only at 2.5 mg/L O₃ over 10 min; molar yields of NDMA from highest to lowest were 11.1% (isoproturon), 1.17% (chlorotoluron), 1.0% (diuron), and 0.73% (fluometuron). The PUH degradation kinetics data during ozonation agreed with the pseudo-first-order model. The rate constant kₒbₛ were 0.31 × 10⁻³–19.8 × 10⁻³ s⁻¹. The kₒbₛ and removal ratios of PUHs during ozonation partially scaled with the mass, LogKₒw, and Henry’s constants of PUHs. Comparisons of measured NDMA-FPs with calculated NDMA-FPs from residual PUH after oxidation showed that the intermediates produced during ozonation facilitated NDMA-FPs; this contribution was also observed for chlorotoluron and isoproturon during ClO₂ oxidation. Examination of reaction mechanisms revealed that tertiary amine ozonation, N-dealkylation, hydroxylation, the cleavage of N–C bonds, ammonification, and nitrification occurred during the ozonation of PUHs, and the dimethylamine (DMA) functional groups could be decomposed directly and transformed into NDMA via the formation of the intermediate unsymmetrical dimethylhydrazine. NDMA is also formed from the reaction between DMA and phenylamino-compounds. Clarifying primary degradation products of PUHs and transformation pathways of NDMA during oxidation processes is useful to optimize treatment processes for water supplies.

Quantifying the sources of atmospheric particles is essential to air quality control but remains challenging, especially for the source apportionment of particles based on number concentration with wide size range. Here, particle number concentrations (PNC) with size range 19–20,000 nm involving four modes Nucleation, Aitken, Accumulation, and Coarse are used to do source apportionment of PNC at the Guangdong Atmospheric Supersite (Heshan) during July–October 2015 by nonnegative matrix factorization (NMF) with 6 factors. For July 2015, separated source apportionments for three different size ranges from collocated instruments nano scanning mobility particle sizer (NSMPS), SMPS, and aerodynamic particle sizer (APS) and for two different size ranges (below and above 100 nm) show similar quantitative source information with that for the one whole size range. The mean absolute difference of contribution percentages of total particle number concentrations (TPNC) based on 5 unique apportioned sources is 5.6 % (4.3–7.6 %) for the instrument segregated apportionment and 4.2 % (0–5.3 %) for the size range segregated apportionment respectively, relative to the one whole apportionment. Moreover, the contribution percentages of TPNC are close to the weighted sum of contribution percentages of all size bins, with a mean absolute difference of 1.1 % (0–3.4 %). In both these two aspects, the consistency among different technical paths proves the matrix factorization by NMF is practically desirable and the simplicity of reducing some steps or calculations saves time. Besides, dust can be identified with the wide size range including larger than 3000 nm. Six apportioned sources in the 4 months are Accumulation (32.4 %), Nucleation (20.0 %), Aitken (15.2 %), traffic (14.6 %), dust (10.6 %), and Coarse (7.1 %). Therefore, NMF would serve as a promising tool for PNC source apportionment with wide size range and conducting the apportionment with the whole size range in one matrix factorization procedure and using the single TPNC contribution percentage are feasible.

Antibiotic resistance genes (ARGs) are now viewed as emerging contaminants posing a potential worldwide human health risk. The degree to which ARGs are transferred to other bacteria via mobile genetic elements (MGEs), including insertion sequences (ISs), plasmids, and phages, has a strong association with their likelihood to function as resistance transfer determinants. Consequently, understanding the structure and function of MGEs is paramount to assessing future health risks associated with ARGs in an environment subjected to strong antibiotic pressure. In this study we used whole genome sequencing, done using MinION and HiSeq platforms, to examine antibiotic resistance determinants among four multidrug resistant bacteria isolated from fish farm effluent in Jeju, South Korea. The combined data was used to ascertain the association between ARGs and MGEs. Hybrid assembly using HiSeq and MinION reads revealed the presence of IncFIB(K) and pVPH2 plasmids, whose sizes were verified using pulsed field gel electrophoresis. Twenty four ARGs and 95 MGEs were identified among the 955 coding sequences annotated on these plasmids. More importantly, 22 of 24 ARGs conferring resistance to various antibiotics were found to be located near MGEs, whereas about a half of the ARGs (11 out of 21) were so in chromosomes. Our results also suggest that the total phenotypic resistance exhibited by the isolates was mainly contributed by these putatively mobilizable ARGs. The study gives genomic insights into the origins of putatively mobilizable ARGs in bacteria subjected to selection pressure.

Considerable human data have shown that the exposure to perfluorooctane sulfonate (PFOS) correlates to the risk of metabolic diseases, however the underlying effects are not clearly elucidated. In this study, we investigated the impacts of PFOS treatment, using in-vivo, ex-vivo and in-vitro approaches, on pancreatic β-cell functions. Mice were oral-gavage with 1 and 5 μg PFOS/g body weight/day for 21 days. The animals showed a significant increase in liver triglycerides, accompanied by a reduction of triglycerides in blood sera and glycogen in livers and muscles. Histological examination of pancreases showed no noticeable changes in the size and number of islets from the control and treatment groups. Immunohistochemistry showed a reduction of staining intensities of insulin and the transcriptional factors (Pdx-1, islet-1) in islets of pancreatic sections from PFOS-treated groups, but no changes in the intensity of Glut2 and glucagon were noted. Transcriptomic study of isolated pancreatic islets treated ex vivo with 1 μM and 10 μM PFOS for 24 h, underlined perturbations of the insulin signaling pathways. Western blot analysis of ex-vivo PFOS-treated islets revealed a significant reduction in the expression levels of the insulin receptor, the IGF1 receptor-β, Pdk1-Akt-mTOR pathways, and Pdx-1. Using the mouse β-cells (Min-6) treated with 1 μM and 10 μM PFOS for 24 h, Western blot analysis consistently showed the PFOS-treatment inhibited Akt-pathway and reduced cellular insulin contents. Moreover, functional studies revealed the inhibitory effects of PFOS on glucose-stimulated insulin-secretion (GSIS) and the rate of ATP production. Our data support the perturbing effects of PFOS on animal metabolism and demonstrate the underlying molecular targets to impair β-cell functions.

It has been shown that chemical modification of chitosan with sulfur (S) functional groups could significantly enhance its chelating capability with heavy metals included Cd(II). However, a molecular level understanding has been lacking. Here, we carried out X-ray absorption fine structure (XAFS) and Fourier transformed infrared (FTIR) spectra studies to bridge this knowledge gap. The results indicate that both Cd–O/N and Cd–S bonds exist in the complex of Cd(II) with dithiocarbamate chitosan (DTC-CTS). S functional groups (dithiocarbamate) in DTC-CTS play the major role in complexation with Cd(II) and S content affects the adsorption mechanism. At low S content, Cd(II) is mainly adsorbed on DTC-CTS as an outer-sphere complex with two monodentate amino groups and two water molecules in tetrahedral configuration. At high S content, Cd adsorption dominantly occurs by formation of an inner-sphere complex with two bidentate mononuclear S ligands in tetrahedral configuration. This investigation provides information on the effectiveness and mechanisms of Cd(II) removal that is critical for evaluating modified chitosan applications for stabilization of Cd(II) in surface water, groundwater, soils and sediments.