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Polycyclic aromatic hydrocarbons (PAHs) are well-acknowledged pro-inflammatory chemicals, but their associations with blood cell-based inflammatory biomarkers need further investigation. Moreover, the effects and mechanisms of essential metals on PAH-related inflammation remain poorly understood. To elucidate the associations of PAHs on inflammatory biomarkers, as well as the effects and mechanisms of essential metals on these associations. A cross-sectional study was conducted on 1388 coke oven workers. We analyzed the modification effects of key essential metal(s) on PAHs-inflammatory biomarkers associations. To explore the possible mechanisms from an inflammation perspective, we performed a bioinformatic analysis on the genes of PAHs and essential metals obtained from the Comparative Toxicogenomics Database (CTD) and performed a mediation analysis. We observed associations of PAHs and essential metals with lymphocyte-to-monocyte ratio (LMR) (P < 0.05). PAH mixtures were inversely associated with LMR (β QGC-index = −0.18, P < 0.001), with 1-hydroxypyrene (1-OH-Pyr) being the most prominent contributor (weight = 63.37 %), whereas a positive association between essential metal mixtures and LMR was observed (β QGC-index = 0.14, P < 0.001), with tin being the most significant contributor (weight = 51.61%). An inverse association of 1-OH-Pyr with LMR was weakened by increased tin exposure (P < 0.05). The CTD database showed that PAHs and tin compounds co-regulated 22 inflammation-associated genes, but they regulated most genes in opposite directions. Further identified the involvement of oxidative stress and mediation analysis showed that the mediation effect of 8-hydroxydeoxyguanosine (8-OHdG) on 1-OH-Pyr-LMR association presented heterogeneity between low and high tin tertile groups (I 2 = 37.84%). 1-OH-Pyr and tin were significantly associated with LMR. Modification effects indicated that the inverse association of 1-OH-Pyr with LMR was mitigated with an increase in tin. The mediation effect of 8-OHdG on the inverse association of 1-OH-Pyr with LMR may be partially dependent on tin. [Display omitted] • PAH mixtures were related to decreased LMR, with pyrene contributing the most. • Essential metals had joint effects on elevated LMR, with tin being predominant. • Tin had a modifying effect on pyrene-LMR association. • Pyrene and tin regulated inflammation-related common genes in opposite directions. • 8-OHdG mediated pyrene-LMR association and partially dependent on the dose of tin. [ABSTRACT FROM AUTHOR]

Epidemiological evidence concerning effects of simultaneous exposure to noise and benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) on renal function remains uncertain. In 2020, a cross-sectional study was conducted among 1160 petrochemical workers in southern China to investigate effects of their co-exposure on estimated glomerular filtration rate (eGFR) and mild renal impairment (MRI). Noise levels were assessed using cumulative noise exposure (CNE). Urinary biomarkers for BTEXS were quantified. We found the majority of workers had exposure levels to noise and BTEXS below China's occupational exposure limits. CNE, trans, trans -muconic acid (tt -MA), and the sum of mandelic acid and phenylglyoxylic acid (PGMA) were linearly associated with decreased eGFR and increased MRI risk. We observed U-shaped associations for both N-acetyl-S-phenyl-L-cysteine (SPMA) and o-methylhippuric acid (2-MHA) with MRI. In further assessing the joint effect of BTEXS (β , −0.164 [95% CI, −0.296 to −0.033]) per quartile increase in all BTEXS metabolites on eGFR using quantile g-computation models, we found SPMA, tt -MA, 2-MHA, and PGMA played pivotal roles. Additionally, the risk of MRI associated with tt -MA was more pronounced in workers with lower CNE levels (P = 0.004). Multiplicative interaction analysis revealed antagonisms of CNE and PGMA on MRI risk (P = 0.034). Thus, our findings reveal negative dose-effect associations between noise and BTEXS mixture exposure and renal function in petrochemical workers. With the exception of toluene, benzene, xylene, ethylbenzene, and styrene are all concerning pollutants for renal dysfunction. Effects of benzene, ethylbenzene, and styrene exposure on renal dysfunction were more pronounced in workers with lower CNE. [Display omitted] • Noise exposure was associated with renal dysfunction in petrochemical workers. • BTEXS metabolites mixture was dose-dependently associated with eGFR decline. • SPMA, tt -MA, 2-MHA, and PGMA were key contributors to joint associations. • SPMA and 2-MHA exhibited nonlinear associations with renal dysfunction. • In workers with lower CNE, tt -MA and PGMA had stronger impacts on renal dysfunction. [ABSTRACT FROM AUTHOR]

The increased applications and production of graphene oxide (GO) make the necessity to study information on the interaction of GO with minerals. In this work, adsorption and desorption were used to study the reversibility of interaction between GO and goethite/kaolinite. Result showed that the pH value, ionic strength, and temperature had significant effects on the adsorption and desorption behavior of GO. Interaction force was stronger between GO and goethite than that of kaolinite. The interaction may be attributed to the electrostatic, hydrogen-bonding, and Lewis acid base interactions. The irreversible interaction between GO and minerals may be a main mechanism for the observed desorption hysteresis. These results are important for evaluating the fate and health risk of GO in the environment. Image 1 • Adsorption and desorption of GO on cationic goethite and anionic kaolinite minerals was studied. • PH value, ionic strength, and temperature influence the adsorption and desorption behavior of GO. • Part of interaction between GO and minerals was irreversible. [ABSTRACT FROM AUTHOR]

Toxic metals can substantially change the bacterial community and functions thereof in aquatic environments. Herein, metal resistance genes (MRGs) are the core genetic foundation for microbial responses to the threats of toxic metals. In this study, waterborne bacteria collected from the Pearl River Estuary (PRE) were separated into the free-living bacteria (FLB) and particle-attached bacteria (PAB), and analyzed using metagenomic approaches. MRGs were ubiquitous in the PRE water and mainly related to Cu, Cr, Zn, Cd and Hg. The levels of PAB MRGs in the PRE water ranged from 8.11 × 109 to 9.93 × 1012 copies/kg, which were significantly higher than those of the FLB (p < 0.01). It could be attributed to a large bacterial population attached on the suspended particulate matters (SPMs), which was evidenced by a significant correlation between the PAB MRGs and 16S rRNA gene levels in the PRE water (p < 0.05). Moreover, the total levels of PAB MRGs were also significantly correlated with those of FLB MRGs in the PRE water. The spatial pattern of MRGs of both FLB and PAB exhibited a declining trend from the low reaches of the PR to the PRE and on to the coastal areas, which was closely related to metal pollution degree. MRGs likely carried by plasmids were also enriched on the SPMs with a range from to 3.85 × 108 to 3.08 × 1012 copies/kg. MRG profiles and taxonomic composition of the predicted MRG hosts were significantly different between the FLB and PAB in the PRE water. Our results suggested that FLB and PAB could behave differential response to heavy metals in the aquatic environments from the perspective of MRGs. [Display omitted] • Both MRGs and those likely carried by plasmids were enriched on the SPMs. • MRG profiles were significantly different between the FLB and PAB in the PRE water. • The levels of MRGs carried by PAB were significantly correlated with those of the FLB. • MRG levels in the PRE water presented positive relationships with metal pollution. • Taxonomic composition of PAB MRG hosts was differentiated from that of FLB MRG hosts. [ABSTRACT FROM AUTHOR]

Ubiquitous polycyclic aromatic hydrocarbons (PAHs) and metals could induce hyperuricemia and oxidative damage individually, while their co-exposure effects on hyperuricemia risk and the potential roles of oxidative damage in these health outcomes remain poorly understood. We conducted a cross-sectional study in 1379 coke oven workers. We evaluated the levels of PAH-metal exposure and oxidative damage by urinary monohydroxy-PAHs, plasma benzo [a]pyrene-7,8-diol-9,10-epoxide-albumin (BPDE-Alb) adducts, urinary metals, urinary 8-iso-prostaglandin-F2α, and urinary 8-hydroxydeoxyguanosine (8-OH-dG). The subjects were classified into cases of hyperuricemia and controls by the levels of blood uric acid. We found that the sum of multiple hydroxyphenanthrene (ΣOH-Phe) was robustly associated with the increase in hyperuricemia risk, while rubidium and strontium had robust protective associations with hyperuricemia risk (P trend <0.05). The risk association of ΣOH-Phe was weaker in workers with high levels of rubidium and strontium [ P for modifying effect (P ME) < 0.030]. The protective association of strontium was more pronounced in workers with higher ΣOH-Phe (P ME = 0.014). We also found that 8-OH-dG was a risk factor for hyperuricemia (P trend = 0.006) and mediated 10.13% of the elevated hyperuricemia risk associated with ΣOH-Phe. Our findings suggested that individual PAHs and metals, as well as their co-exposure, may influence hyperuricemia risk among coke oven workers, with oxidative DNA damage playing a potential mediating role in their associations. [Display omitted] • ΣOH-Phe was robustly associated with the increase of hyperuricemia risk. • Rubidium and strontium had robust protective associations with hyperuricemia risk. • Risk association of ΣOH-Phe was weaker in workers with high rubidium and strontium. • Protective association of strontium was stronger in workers with high ΣOH-Phe. • 8-OH-dG mediated 10.13% of elevated hyperuricemia risk associated with ΣOH-Phe. [ABSTRACT FROM AUTHOR]

Presented herein is a facile approach, which is easy, cost-effective, environmental benign without any secondary environmental pollution and no requirement for post purification, towards the synthesis of graphene oxides (GOs) with different oxidation degrees by ozone treatment. The synthesized GOs with controlled oxidation degrees can not only increase the quantity of oxygen-containing functional groups on GOs surfaces, but also decrease the sizes of GOs sheets to facilitate their dispersion abilities in aqueous solution, as revealed by characterization. The ozonized GOs were further applied as Co(II) adsorbents from aqueous solutions. The adsorption results showed that this adsorption processes was endothermic and spontaneous, and followed the pseudo-second-order kinetics and the Langmuir adsorption models. The microcosmic mechanism displayed that cobalt can complex with the oxygen-containing functional groups on GOs surfaces. As expected, increased adsorption capacities were observed by GOs with higher oxidation degrees. [ABSTRACT FROM AUTHOR]

Highlights: [•] Calculate the pyrolysis of O-methyl S-alkyl and S-methyl O-alkyl thiocarbonates. [•] Compare the kinetic and activation parameters for the experimental and theoretical results. [•] Elucidate the pyrolysis process by natural bond orbital analysis. [ABSTRACT FROM AUTHOR]

Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension. [Display omitted] • 99.4% of Pb was concentrated in blood cells of workers, and primarily (83.1%) existed in cytoplasm, the distribution patterns of Pb in the blood was affected by workplaces. • Pb selectively bound to proteins in blood cells of workers, including hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. • Protein-bound Pb is an earlier and more sensitive indicator than blood lead levels, as it is positively correlated with systolic blood pressure, indicating the risk of hypertension. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atmospheric environmental issues in workplaces should be taken seriously. • Evidence is scarce on the interaction between environmental and occupational factors. • We conducted a cross-sectional study among 363,788 workers in south China in 2020. • PM 2.5 and its components were positively associated with an increased risk of OVD. • Less-dust workers and those exposed to occupational noise and heat were more susceptible. The new round of WHO/ILO Joint Estimates of the Work-related Burden of Disease assessment requires futher research to provide more evidence, especially on the health impact of ambient air pollution around the workplace. However, the evidence linking obstructive ventilatory dysfunction (OVD) to fine particulate matter (PM 2.5) and its chemical components in workers is very limited. Evidence is even more scarce on the interactive effects between occupational factors and particle exposures. We aimed to fill these gaps based on a large ventilatory function examination of workers in southern China. We conducted a cross-sectional study among 363,788 workers in southern China in 2020. The annual average concentration of PM 2.5 and its components were evaluated around the workplace through validated spatiotemporal models. We used mixed-effect models to evaluate the risk of OVD related to PM 2.5 and its components. Results were further stratified by basic characteristics and occupational factors. Among the 305,022 workers, 119,936 were observed with OVD. We found for each interquartile range (IQR) increase in PM 2.5 concentration, the risk of OVD increased by 27.8 (95 % confidence interval (CI): 26.5–29.2 %). The estimates were 10.9 % (95 % CI : 9.7–12.1 %), 15.8 % (95 % CI : 14.5–17.2 %), 2.6 % (95 % CI : 1.4–3.8 %), 17.1 % (95 % CI : 15.9–18.4 %), and 11 % (95 % CI : 9.9–12.2 %), respectively, for each IQR increment in sulfate, nitrate, ammonium salt, organic matter and black carbon. We observed greater effect estimates among females, younger workers, workers with a length of service of 24–45 months, and professional skill workers. Furthermore, it is particularly noteworthy that the noise-exposed workers, high-temperature-exposed workers, and less-dust-exposed workers were at a 5.7–68.2 % greater risk than others. PM 2.5 and its components were significantly associated with an increased risk of OVD, with stronger links among certain vulnerable subgroups. [ABSTRACT FROM AUTHOR]

Natural bacterial isolates from heavily contaminated sites may evolve diverse tolerance strategies, including biosorption, efflux mechanism, and intracellular precipitation under the continually increased stress of toxic lead (Pb) from anthropogenic activities. These strategies utilize a large variety of functional groups in biological macromolecules (e.g., exopolysaccharides (EPSs) and metalloproteins) and inorganic ligands, including carboxyl, phosphate and amide groups, for capturing Pb. The amount and type of binding sites carried by biologically originated materials essentially determines their performance and potential for Pb removal and remediation. Many factors, e.g., metal ion radius, electronegativity, the shape of the cell surface sheath, temperature and pH, are thought to exert significant influences on the abovementioned interactions with Pb. Conclusively, understanding the chemical basis of Pb-binding in these bacteria can allow for the development of effective microbial Pb remediation technologies and further elucidation of Pb cycling in the environment. Unlabelled Image [ABSTRACT FROM AUTHOR]

Highlights: [•] Amidoxime-functionalized silica coated Fe3O4 was synthesized and characterized. [•] Fe3O4@SiO2-AO exhibited fast and efficient sorption for U(VI). [•] Fe3O4@SiO2-AO could be easily separated from aqueous solutions with a magnet. [•] Fe3O4@SiO2-AO was resistant to acid corrosion. [•] U(VI)-loaded Fe3O4@SiO2-AO could be efficiently regenerated and reused. [Copyright &y& Elsevier]

Bacterial degradation is unequivocally considered as an important way for the cleanup of polycyclic aromatic hydrocarbon (PAHs) in the aquatic environment. However, the diversity and distribution of PAH-degrading bacterial communities and PAH degradation-related genes (PAHDGs) in ambient environment need to be investigated. In this study, bacteria in the water of the Pearl River Estuary (PRE) were initially separated as the particle-attached bacteria (PAB) and free-living bacteria (FLB), and were further characterized using metagenomic approaches. Proteobacteria (80.1 %) was identified as the most abundant PAH-degrading phylum in the PRE water, followed by Bacteroidetes, Actinobacteria, and Firmicutes. A substantial difference in the community structure was observed between PAH-degrading PAB and FLB. Both of PAH-degrading bacteria and PAHDGs were enriched on the suspended particulate matters (SPMs), with the range of enrichment factor (EF) from 7.84 × 104 to 6.64 × 106 (PAH-degrading bacteria) and from 1.14 × 103 to 1.76 × 105 (PAHDGs). The levels of PAH-degrading bacteria 16 S rRNA genes and PAHDGs on the SPMs were both significantly correlated with those in the aqueous phase (AP) in the PRE water (p < 0.05), indicating a dynamic distribution of PAH-degrading bacteria between these two phases. The total PAH concentrations on the SPMs of the PRE water were also significantly correlated with the total PAHDG levels in the PAB (p < 0.05). Our results suggested that the SPMs could be the important compartment for the elimination of PAHs from the aquatic environment. • Proteobacteria was identified as the most abundant PAH-degrading phylum in the PRE. • PAH-degrading bacteria were enriched on the suspended particulate matters (SPMs). • There was a dynamic equilibrium of PAH-degrading bacteria between the SPMs and AP. • SPMs were the main location for bacterial degradation of PAHs in aquatic environment. [ABSTRACT FROM AUTHOR]

• Occupational exposures were associated with DNA methylation aging biomarkers. • Benzene and trichloroethylene exposures increased epigenetic age acceleration. • Epigenetic aging biomarkers capture impacts of environmental chemicals on health. Epigenetic aging biomarkers are associated with increased morbidity and mortality. We evaluated if occupational exposure to three established chemical carcinogens is associated with acceleration of epigenetic aging. We studied workers in China occupationally exposed to benzene, trichloroethylene (TCE) or formaldehyde by measuring personal air exposures prior to blood collection. Unexposed controls matched by age and sex were selected from nearby factories. We measured leukocyte DNA methylation (DNAm) in peripheral white blood cells using the Infinium HumanMethylation450 BeadChip to calculate five epigenetic aging clocks and DNAmTL, a biomarker associated with leukocyte telomere length and cell replication. We tested associations between exposure intensity and epigenetic age acceleration (EAA), defined as the residuals of regressing the DNAm aging biomarker on chronological age, matching factors and potential confounders. Median differences in EAA between exposure groups were tested using a permutation test with exact p -values. Epigenetic clocks were strongly correlated with age (Spearman r > 0.8) in all three occupational studies. There was a positive exposure-response relationship between benzene and the Skin-Blood Clock EAA biomarker: median EAA was −0.91 years in controls (n = 44), 0.78 years in workers exposed to <10 ppm (n = 41; mean benzene = 1.35 ppm; p = 0.034 vs. controls), and 2.10 years in workers exposed to ≥10 ppm (n = 9; mean benzene = 27.3 ppm; p = 0.019 vs. controls; p trend = 0.0021). In the TCE study, control workers had a median Skin-Blood Clock EAA of −0.54 years (n = 71) compared to 1.63 years among workers exposed to <10 ppm of TCE (n = 27; mean TCE = 4.22 ppm; p = 0.035). We observed no evidence of EAA associations with formaldehyde exposure (39 controls, 31 exposed). Occupational benzene and TCE exposure were associated with increased epigenetic age acceleration measured by the Skin-Blood Clock. For TCE, there was some evidence of epigenetic age acceleration for lower exposures compared to controls. Our results suggest that some chemical carcinogens may accelerate epigenetic aging. [ABSTRACT FROM AUTHOR]

Fish consumption is one of the major ways through which humans receive exposure to mercury (Hg). The existing forms of Hg in food, particularly Hg bound to proteins, may affect the absorption of Hg by humans and subsequently its potentially toxic effects. However, the knowledge regarding Hg-binding proteins in edible fish muscle is scarce. In the present study, salmon and tuna fish muscles, collected from seven different regions and countries, were analyzed using metallomics- and proteomics-based techniques. The concentration of Hg in sashimi samples ranged from 4.4 to 317.4 ng/g. Size exclusion chromatography (SEC) coupled with inductively coupled plasma mass spectrometer (ICP-MS) showed that beta-actin was a novel Hg-binding protein from the fish muscles, and this protein could also bind bismuth (Bi), silver (Ag), and copper (Cu). Hg bound to beta-actin accounted for approximately 30.2–37.6% of the total Hg in the tuna muscles and was significantly correlated to total Hg in the fish muscles (r = 0.98, p < 0.01) and in the fraction of soluble proteins (r = 0.94, p < 0.01). These findings suggest that proteins act as the main Hg accumulation sites in edible fish; thus, increasing human exposure to Hg following gastrointestinal digestion. • More than half of Hg was deposited in the soluble protein fraction of fish muscle. • Beta-actin was identified as a novel Hg-binding protein in the fish muscle. • More than 30% of the total Hg in tuna muscle was bound to beta-actin. [ABSTRACT FROM AUTHOR]