Environmental and dietary exposure to 24 polycyclic aromatic hydrocarbons in a typical Chinese coking plant.

Polycyclic aromatic hydrocarbons (PAHs), known for their health risks, are prevalent in the environment, with the coking industry being a major source of their emissions. To bridge the knowledge gap concerning the relationship between environmental and dietary PAH exposure, we explore this complex interplay by investigating the dietary exposure characteristics of 24 PAHs within a typical Chinese coking plant and their association with environmental pollution. Our research revealed Nap and Fle as primary dietary contaminants, emphasizing the significant influence of soil and atmospheric pollution on PAH exposure. We subjected our data to non-metric multidimensional scaling (NMDS), Spearman correlation analysis, Lasso regression, and Weighted Quantile Sum (WQS) regression to delve into this multifaceted phenomenon. NMDS reveals that dietary PAH exposure, especially within the high molecular weight (HMW) group, is common both within and around the coking plant. This suggests that meals prepared within the plant may be contaminated, posing health risks to coking plant workers. Furthermore, our assessment of dietary exposure risk highlights Nap and Fle as the primary dietary contaminants, with BaP and DahA raising concerns due to their higher carcinogenic potential. Our findings indicate that dietary exposure often exceeds acceptable limits, particularly for coking plant workers. Correlation analyses uncover the dominant roles of soil and atmospheric pollution in shaping dietary PAH exposure. Soil contamination significantly impacts specific PAHs, while atmospheric pollution contributes to others. Additionally, WQS regression emphasizes the substantial influence of soil and drinking water on dietary PAHs. In summary, our study sheds light on the dietary exposure characteristics of PAHs in a typical Chinese coking plant and their intricate interplay with environmental factors. These findings underscore the need for comprehensive strategies to mitigate PAH exposure so as to safeguard both human health and the environment in affected regions.

Spatial distribution, environmental behavior, and health risk assessment of PAHs in soils at prototype coking plants in Shanxi, China: Stable carbon isotope and molecular composition analyses.

To investigate the environmental behavior of and carcinogenic risk posed by 16 priority-controlled polycyclic aromatic hydrocarbons (PAHs), soil samples and air samples from the coke oven top were collected in two prototype coking plants (named PF and JD). The PF soils contained more PAHs than the JD soils because the PF plant employed the side-charging technique and had a lower coke oven height. The soils from both plants contained enough PAHs to pose a carcinogenic risk, and this risk was higher in the PF plant. Data were collected on the source characteristic spectrum of stable carbon isotopic composition (δ13C) of PAHs emitted from the coke oven top (δ13C values of -36.02‰ to -32.05‰ for gaseous PAHs and -34.09‰ to -25.28‰ for particulate PAHs), and these data fill a research gap and may be referenced for isotopic-technology-based source apportionment. Diagnostic ratios and isotopic technology revealed that the coking plant soils were mainly influenced by the coking process, followed by vehicle exhaust; the soils near the boundary of each plant were slightly affected by C3 plant burning. For most PAHs [excluding fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-c,d)pyrene, and dibenzo(a,h)anthracene], the dominant migration process was the net volatilization of PAHs from soil to air. In the PF plant, 13C was depleted in gaseous PAHs during volatilization.

Healthy lifestyle and essential metals attenuated association of polycyclic aromatic hydrocarbons with heart rate variability in coke oven workers.

Whether adopting healthy lifestyles and maintaining moderate levels of essential metals could attenuate the reduction of heart rate variability (HRV) related to polycyclic aromatic hydrocarbons (PAHs) exposure are largely unknown. In this study, we measured urinary metals and PAHs as well as HRV, and constructed a healthy lifestyle score in 1267 coke oven workers. Linear regression models were used to explore the association of healthy lifestyle score and essential metals with HRV, and interaction analysis was performed to investigate the potential interaction between healthy lifestyle score, essential metals, and PAHs on HRV. Mean age of the participants was 41.9 years (84.5% male). Per one point higher healthy lifestyle score was associated with a 2.5% (95% CI, 1.0%-3.9%) higher standard deviation of all normal to normal intervals (SDNN), 2.1% (95% CI, 0.5%-3.6%) higher root mean square of successive differences in adjacent NN intervals (r-MSSD), 4.3% (95% CI, 0.4%-8.2%) higher low frequency, 4.4% (95% CI, 0.2%-8.5%) higher high frequency, and 4.4% (95% CI, 1.2%-7.6%) higher total power, respectively. Urinary level of chromium was positively associated with HRV indices, with the corresponding ß (95% CI) (%) was 5.17 (2.84, 7.50) for SDNN, 4.29 (1.74, 6.84) for r-MSSD, 12.26 (6.08, 18.45) for low frequency, 12.61 (5.87, 19.36) for high frequency, and 11.31 (6.19, 16.43) for total power. Additionally, a significant interaction was found between healthy lifestyle score and urinary total hydroxynaphthalene on SDNN (Pinteraction = 0.04), and higher level of urinary chromium could attenuate the adverse effect of total hydroxynaphthalene level on HRV (all Pinteraction <0.05). Findings of our study suggest adopting healthy lifestyle and maintaining a relatively high level of chromium might attenuate the reduction of HRV related to total hydroxynaphthalene exposure.

Source apportionment and source specific health risk assessment of HMs and PAHs in soils with an integrated framework in a typical cold agricultural region in China.

A new innovative methodology system framework for source apportionment and source-specific risk assessment has been proposed and actively applied to identify the contamination characteristics, oriented sources and health risks associated with contamination levels of Heavy metals (HMs) and Polycyclic Aromatic Hydrocarbons (PAHs) in soils, a typical cold agricultural region in Northeastern China. To achieve this meaningful goal, a large-scale dataset including 1780 top soil samples, 10 HMs and 16 priority PAHs has been organized and collected from a typical study area in China. The total concentrations of the 10 selected HMs in study area range from 0.05 to 2147.40 mg/kg, with an average of 549.25 ± 541.37 mg/kg. The average concentrations of PAHs for (3-6)-rings are 16.60 ± 18.90, 26.40 ± 28.20, 9.51 ± 13.00 and 1.99 ± 5.30 ng/g, respectively. On the base of optimized literature source fingerprints for HM and PAH, a widely used receptor model, positive matrix factorization (PMF) has been applied to apportion the contamination sources HMs and PAHs in soils. Then source-specific health risk of soil HMs and PAHs have been assessed using the probabilistic incremental lifetime cancer risk model incorporated with source apportionment results data. Fertilizer residues/coke oven comprise the primary contamination source contributors of HMs and PAHs with corresponding contributions of 32.23 % and 27.93 % for HMs and 37.94 % for PAHs. Fertilizer/pesticide residues contributes most to the risks of soil HMs (28.8 %), followed by fossil fuel combustion (24.6 %), mining activities (20.2 %), traffic and vehicle emission (16.3 %) and electroplating/dyeing (14.1 %). Meanwhile, the ranking of health risks from the five identified contamination sources of soil PAHs are resident discharge, coal-fired boilers, coke oven emission, gasoline combustion and power plant, with the contribution of 27.1 %, 25.3 %, 17.3 %, 15.5 % and 14.8 %. And relatively, source-specific risk assessment demonstrates fossil fuel and coal combustion contribute the greatest impact to the total risk of HMs and PAHs (61.7 % and 56.1 %), respectively. This study provides a good example of how the source specific health risk assessment can be utilized to reduce the contamination in soils.

Nontarget Screening of Novel Urinary Biomarkers for Occupational Exposure to Toxic Chemicals from Coking Industry Using HPLC-QTOF-MS.

High-resolution mass spectrometry is an advanced technique for comprehensive screening of toxic chemicals. In this study, urine samples were collected from both an occupationally exposed population at a coking site and normal inhabitants to identify novel urinary biomarkers for occupational exposure to coking contaminants. A coking-site-appropriate analytical method was developed for unknown chemical screening. Through nontarget screening, 515 differential features were identified, and finally, 32 differential compounds were confirmed as candidates for the current study, including 13 polycyclic aromatic hydrocarbon (PAH) metabolites. Besides monohydroxy-PAHs (such as 1-&2-naphthol, 2-&9-hydroxyfluorene, 2-&4-phenanthrol, and 1-&2-hydroxypyrene), many other PAH metabolites including dihydroxy metabolites, PAH oxide, and sulfate conjugate were detected, suggesting that the quantification based solely on monohydroxy-PAHs significantly underestimated the human exposure to PAHs. Furthermore, several novel compounds were recognized that could be considered as biomarkers for the exposure to coking contaminants, including quinolin-2-ol (1.10 ± 0.44 ng/mL), naphthylmethanols (11.4 ± 5.47 ng/mL), N-hydroxy-1-aminonaphthalene (0.78 ± 0.43 ng/mL), hydroxydibenzofurans (17.4 ± 7.85 ng/mL), hydroxyanthraquinone (0.13 ± 0.053 ng/mL), and hydroxybiphenyl (2.70 ± 1.03 ng/mL). Despite their lower levels compared with hydroxy-PAHs (95.1 ± 30.8 ng/mL), their severe toxicities should not be overlooked. The study provides a nontarget screening approach to identify chemicals in human urine, which is crucial for accurately assessing the health risks of toxic chemicals in the coking industry.

Treatment of coking wastewater using a needle coke electro-Fenton cathode: optimizing of COD, NH4+-N, and TOC removal and characterization of pollutants.

Coking wastewater is a typical organic refractory wastewater characterized by high chemical oxygen demand (COD), NH4+-N, and total organic carbon (TOC). Herein, coking wastewater was treated using a heterogeneous electro-Fenton (EF) system comprising a novel iron-loaded needle coke composite cathode (Fe-NCCC) and a dimensionally stable anode. The response surface methodology was used to optimize the reaction conditions. The predicted and actual COD removal rates were 92.13 and 89.96% under optimum conditions of an applied voltage of 4.92 V, an electrode spacing of 2.29 cm, and an initial pH of 3.01. The optimized removal rate of NH4+-N and TOC was 84.12 and 73.44%, respectively. The color of coking wastewater decreased from 250-fold to colorless, and the BOD5/COD increased from 0.126 to 0.34. Gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy show that macromolecular heterocyclic organic compounds decomposed into straight-chain small molecules and even completely mineralized. The energy consumption of the EF process was 23.5 RMB Yuan per cubic meter of coking wastewater. The EF system comprising the Fe-NCCC can effectively remove pollutants from coking wastewater, has low electricity consumption, and can simultaneously reduce various pollution indicators with potential applications in the treatment of high-concentration and difficult-to-degrade organic wastewater.

Chain-mediating effect of interaction between telomeres and mitochondria under oxidative stress in coke oven workers.

Coke oven emissions (COEs) exposure leads to oxidative stress, an imbalance between oxidant production and antioxidant defence in the body, which then leads to shortened relative telomere length (RTL) and reduced mitochondrial DNA copy number (mtDNAcn), ultimately leading to ageing and disease. By analysing the relationship among COEs, oxidative stress, RTL and mtDNAcn, we investigated the chain-mediating effects of oxidative stress and telomeres on mitochondrial damage and mitochondria on telomere damage in coke oven workers. A total of 779 subjects were included in the study. Cumulative COEs exposure concentrations were estimated, and the RTL and mtDNAcn of peripheral blood leukocytes were measured using real-time fluorescence quantitative PCR. Total antioxidant capacity (T-AOC) was measured to reflect the level of oxidative stress. The data were statistically analysed using SPSS 21.0 software and discussed using mediation effect analysis. After adjusting for age, sex, smoking, drinking and BMI, generalised linear model revealed dose-response associations between COEs and T-AOC, RTL and mtDNAcn, respectively. (Ptrend < 0.05). The results of chain-mediating effect showed that the proportion of the chain-mediating effect of "CED-COEs→T-AOC→ RTL→mtDNAcn" was 0.82% (ß = -0.0005, 95% CI = [-0.0012, -0.0001]), and the proportion of the chain-mediating effect of "CED-COEs→T-AOC→ mtDNAcn → RTL ″ was 2.64% (ß = -0.0013, 95% CI = [-0.0025, -0.0004]). After oxidative stress is induced by COEs, mitochondria and telomeres may interact with each other while leading further to potential bodily damage. This study provides clues to explore the association between mitochondria and telomeres.

Focusing on testosterone levels in male: A half-longitudinal study of polycyclic aromatic hydrocarbon exposure and diastolic blood pressure in coke oven workers.

Polycyclic aromatic hydrocarbons (PAHs) can interfere with testosterone levels, and low levels of testosterone are associated with increased cardiovascular events. To explore the role of testosterone in PAHs exposure and cardiovascular health, we used data from the 2011-2016 National Health and Nutrition Examination Survey (NHANES) and a longitudinal database of 332 male coke oven workers from China. The urine PAHs, tobacco metabolites and plasma testosterone levels of coke oven workers were measured. There were inverse associations between serum (plasma) testosterone concentrations and the risk of dysarteriotony and dyslipidemia among the NHANES participants and coke oven workers. The results of the cross-lagged panel analysis among workers showed that the decrease in testosterone preceded the increase in diastolic blood pressure (DBP), and the absolute value of the path coefficient from baseline testosterone to follow-up DBP (ß2 = -8.162, P = 0.077) was significantly larger than the absolute value of the path coefficient from baseline DBP to follow-up testosterone (ß1 = -0.001, P = 0.781). Results from the half-longitudinal mediation analysis showed that baseline hydroxyfluorene predicted significant decreases in plasma testosterone from baseline to follow-up (path a: 0.71, 95% CI: 1.26, -0.16), whereas plasma testosterone at baseline also predicted significant increments in DBP from baseline to follow-up (path b: 9.22, 95% CI: 17.24, -1.19). The indirect effect of PAHs on DBP via plasma testosterone level was marginally significant (test for indirect effects a*b (P = 0.08)). In conclusion, testosterone level is a longitudinal precursor to increased DBP and plays an essential role in the association between PAHs exposure and damage to the cardiovascular system. Coke oven workers with low plasma testosterone levels are more likely to experience adverse changes in blood pressure and lipid levels after exposure to PAHs.

The effect of high polycyclic aromatic hydrocarbon exposure on biological aging indicators.

BACKGROUND: Aging represents a serious health and socioeconomic concern for our society. However, not all people age in the same way and air pollution has been shown to largely impact this process. We explored whether polycyclic aromatic hydrocarbons (PAHs), excellent fossil and wood burning tracers, accelerate biological aging detected by lymphocytes DNA methylation age (DNAmAge) and telomere length (TL), early nuclear DNA (nDNA) hallmarks of non-mitotic and mitotic cellular aging, and mitochondrial DNA copy number (mtDNAcn). METHODS: The study population consisted of 49 male noncurrent-smoking coke-oven workers and 44 matched controls. Occupational and environmental sources of PAH exposures were evaluated by structured questionnaire and internal dose (urinary 1-pyrenol). We estimated Occup_PAHs, the product of 1-pyrenol and years of employment as coke-oven workers, and Environ_PAHs, from multiple items (diet, indoor and outdoor). Biological aging was determined by DNAmAge, via pyrosequencing, and by TL and mtDNAcn, via quantitative polymerase chain reaction. Genomic instability markers in lymphocytes as target dose [anti-benzo[a]pyrene diolepoxide (anti-BPDE)-DNA adduct], genetic instability (micronuclei), gene-specific (p53, IL6 and HIC1) and global (Alu and LINE-1 repeats) DNA methylation, and genetic polymorphisms (GSTM1) were also evaluated in the latent variable nDNA_changes. Structural equation modelling (SEM) analysis evaluated these multifaceted relationships. RESULTS: In univariate analysis, biological aging was higher in coke-oven workers than controls as detected by higher percentage of subjects with biological age older than chronological age (AgeAcc ≥ 0, p = 0.007) and TL (p = 0.038), mtDNAcn was instead similar. Genomic instability, i.e., genotoxic and epigenetic alterations (LINE-1, p53 and Alu) and latent variable nDNA_changes were higher in workers (p < 0.001). In SEM analysis, DNAmAge and TL were positively correlated with Occup_PAHs (p < 0.0001). Instead, mtDNAcn is positively correlated with the latent variable nDNA_changes (p < 0.0001) which is in turn triggered by Occup_PAHs and Environ_PAHs. CONCLUSIONS: Occupational PAHs exposure influences DNAmAge and TL, suggesting that PAHs target both non-mitotic and mitotic mechanisms and made coke-oven workers biologically older. Also, differences in mtDNAcn, which is modified through nDNA alterations, triggered by environmental and occupational PAH exposure, suggested a nuclear-mitochondrial core-axis of aging. By decreasing this risky gerontogenic exposure, biological aging and the consequent age-related diseases could be prevented.

Tertiary treatment of coke-oven wastewater using suspended and immobilized whole live cells of constructed bacterial-microalgal consortium: modeling and optimization using ANN-GA hybrid methodology.

Coke-oven wastewater (CW), containing an array of toxic pollutants above permissible limits even after conventional primary and secondary treatment, needs a tertiary (polishing) step to meet the statutory limit. In the present study, a suitable bacterial-microalgal consortium (Culture C) was constructed using bacterial (Culture B: Bacillus sp. NITD 19) and microalgal (Culture A: a consortium of Chlorella sp. and Synechococcus sp.) cultures at different ratios (v/v) and the potential of these cultures for tertiary treatment of CW was assessed. Culture C4 (Culture B:Culture A = 1:4) with inoculum size: 10% (v/v) was selected for the treatment of wastewater since the maximum growth (3.08 ± 0.57 g/L) and maximum chlorophyll content (4.05 ± 0.66 mg/L) were achieved for such culture in PLE-enriched BG-11 medium. During treatment of real secondary treated coke-oven effluent using Culture C4 in a closed photobioreactor, the removal of phenol (80.32 ± 2.76%), ammonium ions (47.85 ± 1.83%), fluoride (65.0 ± 4.12%), and nitrate (39.45 ± 3.42%) was observed after 24 h. In a packed bed bioreactor containing immobilized C4 culture, the maximum removal was obtained at the lowest flow rate (20 mL/h) and highest column bed height (20 cm). Artificial intelligence-based techniques were used for modeling and optimization of the process.

Effect of Club cell secretory proteins on the association of tobacco smoke and PAH co-exposure with lung function decline: A longitudinal observation of Chinese coke oven workers.

BACKGROUND: Exposure to polycyclic aromatic hydrocarbons (PAH) and tobacco smoke is associated with epithelial damage and reduced lung function. Club cell secretory protein (CC16) is a known biomarker for lung epithelial cells. However, the potential relationships between PAH and tobacco smoke exposure, CC16 levels, and reduced lung function remain unclear. OBJECTIVES: This longitudinal study aimed to explore the potential role of CC16 in the association of tobacco smoke and PAH co-exposure with lung function. METHODS: We enrolled 313 workers from a coking plant in China in 2014 and followed them up in 2019. The concentrations of PAH and nicotine metabolites in urine were determined using high-performance liquid chromatography (HPLC) with a fluorescence detector and HPLC-tandem mass spectrometry, respectively. The plasma CC16 concentration was determined using an enzyme-linked immunosorbent assay. RESULTS: An analysis of the generalized estimating equation showed that each 1-unit increase in log-transformation of the last tertile of trans-3'-hydroxycotinine (3HC) was associated with a 3.30 ng/ml decrease in CC16. Restricted cubic spline analysis revealed a significant nonlinear dose-effect association between cotinine (COT) and CC16 (Pnonlinear = 0.018). In the low- CC16 subgroup, we found a significant association between total nicotine metabolites and forced vital capacity (FVC%) (ß: 1.45, 95% CI: 2.87, -0.03), and the associations of nicotine (NIC), COT, and 3HC with FVC% were all of marginal significance. High levels of total hydroxyl polycyclic aromatic hydrocarbons (ΣOH-PAH) and NIC in the urine had an interactive effect on the decline of CC16 (P < 0.05). Cross-lagged panel analysis indicated that the decrease in CC16 preceded the decrease in FVC%. CC16 mediated the association between elevated nicotine metabolites and decreased FVC% in the low- CC16 subgroup. CONCLUSIONS: CC16 plays an essential role in the association of PAH and tobacco smoke exposure with reduced lung function. Coke oven workers with low plasma CC16 levels are more likely to experience decreased lung function after tobacco smoke exposure.

Spatial distribution, source identification, and human health risk assessment of PAHs and their derivatives in soils nearby the coke plants.

The coking industry can generate large amounts of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, which may negatively impact the environment and human health. In this study, soils nearby a typical coking plant were sampled to assess the impact of coke production on the surrounding residential areas and human health. The mean concentration of PAHs and their derivatives in residential area soils nearby the coke plant was 4270 ng/g dw, which was 1 order of magnitude higher than that observed in areas far from the coke plant and approximately 4 times lower than that revealed the coke plant. In addition, the results showed that coking processing area was the most contaminant area of the coke plant (mean: 74.4 µg/g dw), where was also the main source of pollutants in residential areas. In terms of vertical soils in coking plant, the maximum levels of chemicals (mean: 205 µg/g dw) were presented at the leakage of underground pipelines, where were much higher than those in surface soils, and decreased with the increase of depth. The analysis of variance (ANOVA) results showed obvious differences in the concentrations of 6-nitrochrysene between the plant, residential areas and control areas. Meanwhile, 6-nitrochrysene had potential cancer risk (CR) for human in the coking site. Thus, 6-nitrochrysene was the most noteworthy PAH derivatives. Furthermore, the CR (mean: 5.94 × 10-5) and toxic equivalent quantities (TEQs) (mean: 14.8 µg·TEQ/g) of PAHs and their derivatives was assessed in this study. This finding suggested that PAHs and their derivatives especially those extremely toxic chemicals (Nitro-PAHs (NPAHs) and Br/Cl-PAHs (XPAHs)) might pose a potential health risk to residents nearby the coke plant. The current study provides further insights into the pollution characteristics of PAHs and their derivatives in coke plants and potential risks to the workers and surrounding residents.

Effects of H19/SAHH/DNMT1 on the oxidative DNA damage related to benzo[a]pyrene exposure.

The mechanisms that long noncoding RNA (lncRNA) H19 binding to S-adenosylhomocysteine hydrolase (SAHH) interacted with DNA methyltransferase 1 (DNMT1) and then regulated DNA damage caused by polycyclic aromatic hydrocarbons (PAHs) remain unclear. A total of 146 occupational workers in a Chinese coke-oven plant in 2014 were included in the final analyses. We used high-performance liquid chromatography mass spectrometry (HPLC-MS) equipped to detect urine biomarkers of PAHs exposure, including 2-hydroxynaphthalene (2-NAP), 2-hydroxyfluorene (2-FLU), 9-hydroxyphenanthrene (9-PHE) and 1-hydroxypyrene (1-OHP). The levels of SAM and SAH in plasma were detected by HPLC-ultraviolet. By constructing various BEAS-2B cell models exposed to 16 µM benzo[a]pyrene (BaP) for 24 h, toxicological parameters reflecting distinct mechanisms were evaluated. We documented that urinary 1-hydroxypyrene (1-OHP) levels were positively associated with blood H19 RNA expression (OR: 1.51, 95% CI: 1.03-2.19), but opposite to plasma SAHH activity (OR: 0.63, 95% CI: 0.41-0.98) in coke oven workers. Moreover, by constructing various BEAS-2B cell models exposed to benzo[a]pyrene (BaP), we investigated that H19 binding to SAHH exaggerated DNMT1 expressions and activity. Suppression of H19 enhanced the interaction of SAHH and DNMT1 in BaP-treated cells, decreased eight-oxoguanine DNA glycosylase 1 (OGG1) methylation, reduced oxidative DNA damage and lessened S phase arrest. However, SAHH or DNMT1 single knockdown and SAHH/DNMT1 double knockdown showed the opposite trend. A H19/SAHH/DNMT1 axis was involved in OGG1 methylation, oxidative DNA damage and cell cycle arrest by carcinogen BaP.

Cytogenetic analysis of coke oven workers in Eastern Slovakia.

OBJECTIVE: Our study aimed to evaluate the extent of polycyclic aromatic hydrocarbon (PAH) exposure in coke oven workers from Eastern Slovakia by cytogenetic analysis of human peripheral lymphocytes. METHODS: A total of 81 peripheral blood samples were collected from PAH-exposed workers (mean age 45.84 ± 9.73 years) and 30 samples constituted the control group (41.93 ± 15.39 years). The samples were processed using routine cytological analysis. Conventional cytogenetic analysis of human peripheral lymphocytes has been used to evaluate the effects of PAHs. RESULTS: Comparison of the aberrant cells in the total exposed with the controls showed a significant difference (p < 0.05). A high level of significance (p < 0.001) was observed when comparing the gaps between the exposed group and the control group. There was a significant difference (p < 0.01) in aberrant cells and chromatid breaks (p < 0.05) in the GR1 working subgroup compared with the control group. The results of the correlation analysis did not show a significant relationship between the length of occupational exposure and the frequency of aberrant cells (r = 0.071, p = 0.529). Similarly, no association was observed between smoking among coke plant workers and the frequency of aberrant cells (r = 0.117, p = 0.538). CONCLUSION: Cytogenetic analysis showed an increased frequency of chromosomal aberrations in coke oven workers in Eastern Slovakia.

[Association among urinary polycyclic aromatic hydrocarbons metabolites, SAHH activity and H19 expression in coke oven workers].

Objective: To investigate the relationship of polycyclic aromatic hydrocarbons (PAHs) exposure, S-adenosylhomocysteine hydrolase (SAHH) activity and long noncoding RNA H19 gene expression in the urine of coke oven workers. Methods: In September 2019, in a coking plant in Taiyuan City, 146 male workers who had worked in coke oven operations for one year were selected through a completely random sampling method, and their basic personal information was collected by questionnaire survey, and blood and urine samples were collected. The levels of 4 PAHs metabolites 2-hydroxfluorene (2-FLU), 2- hydroxynaphthalene (2-NAP), 9-hydroxyphenanthren (9-PHE), and 1-hydroxypyrene (1-OHP) in urine were detected by high performance liquid chromatography (HPLC) -fluorescence detection method. HPLC-UV detection method was used to detect the content of S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) in plasma, and the SAHH activity value was obtained by calculating the ratio. Reverse transcription PCR method was used to determine the H19 gene expression level. Urine levels of 2-FLU, 2-NAP, 9-PHE, and 1-OHP were divided into Q(1), Q(2), Q(3), and Q(4) groups according to quartiles (P(25), P(50), P(75)). Regression, trend test and restricted cubic splines were used to analyze the relationship among PAHs metabolites, SAHH activity, H19 gene expression and their dose-response. Results: The median age of coke oven workers was 39.60 years old, the median length of service was 20.38 years, and the urinary levels of 2-FLU, 2-NAP, 9- PHE, and 1-OHP were 0.29, 0.74, 0.09, and 0.06 µg/mmol Cr, respectively. The levels of 2-FLU, 2-NAP and 9-PHE in the urine of workers were significantly different between groups with different 1-OHP levels (P<0.05). After adjusting for age, length of service, smoking, drinking, and levels of 2-FLU, 2-NAP and 9-PHE, SAHH activity decreased with the increase of urinary 1-OHP level (OR=0.63, 95%CI: 0.41-0.98, P=0.038), showing a nonlinear relationship (P(nonlinear)= 0.030). H19 gene expression increased with the increase of urinary 1- OHP level (OR=1.51, 95%CI: 1.03-2.19, P=0.033), there was a linear relationship (P(trend)= 0.058). The relationship between the other three metabolites in urine and SAHH activity and H19 gene expression was not statistically significant (P>0.05) . Conclusion: Urinary 1-OHP level may be a risk factor for decreased SAHH activity and increased H19 gene expression in coke oven workers.

[Study on the relationship between the pathological type of lung cancer caused by coke oven discharge and the contact type and exposure time].

Objective: To study the pathological types of lung cancer caused by coke oven emissions and analyze the correlation between different exposure levels. Methods: In October 2020, the relevant data of 86 confirmed cases of lung cancer caused by coke oven emissions (including basic information of patients, relevant occupational exposure and clinical data) were collected, The workers were grouped according to the different COEs concentrations in their posts: workers in auxiliary posts were taken as the low exposure group (11 persons) , The workers at coke side and furnace bottom are the medium exposure group (14 persons) , and the workers at furnace top are the high exposure group (61 persons) , and the correlation between pathological types of lung cancer and different exposure levels was analyzed. Results: There was no significant difference in age and length of service among the groups (P>0.05) ; The number of lung cancer cases and pathological types among workers in each group were statistically significant (P=0.044) . After adjusting for interference factors, the number of undifferentiated cancers (mainly small cell lung cancer) increased with the increase of exposure level, with a statistically significant difference (P=0.001) . The incidence of lung cancer increased gradually with the length of service, and the incidence rate of lung cancer among workers of different working ages was statistically significant (P<0.05) . Conclusion: Undifferentiated small cell carcinoma is the most common pathological type of lung cancer caused by coke oven emissions, and the incidence of lung cancer tends to increase with the length of service.

Treatment of organic pollutants in coke plant wastewater by micro-nanometer catalytic ozonation, A/A/O and reverse osmosis membrane.

Coking wastewater has a complex and highly concentrated chemical composition which is toxic and does not biodegrade easily. Treating the organic pollutants in this wastewater is very challenging. The toxic substances in this wastewater make traditional biotechnological treatments inefficient. Current wastewater treatment studies are based on unit processes, and no full process studies could be found. This study used the micro-nanometer catalytic ozonation process as a pretreatment unit, and reverse osmosis membrane treatment as a depth processing unit to improve the effect of the coking wastewater degradation. The micro-nanometer catalytic ozonation pretreatment greatly improves the biodegradability of the coking wastewater and promotes the coking wastewater degradation in the anoxia/anaerobic/oxic (A/A/O) system. The integrated coagulation air flotation-micro-nanometer catalytic ozonation-A/A/O-reverse osmosis membrane system can remove 98% of the chemical oxygen demand, which meets the direct emission standard of the new national standard (China). The dominant genera in the A/A/O biochemical reactor were Thioalkalimicrobium, Proteiniphilum, Azoarcu, Bacillus, Fontibacter, and Taibaiella. This work provides a novel approach for the degradation of high-concentration organic wastewater and lays a solid foundation for the restoration of environmental water bodies.

Preparation of Fe-loaded needle coke particle electrodes and utilisation in three-dimensional electro-Fenton oxidation of coking wastewater.

Novel iron-loaded needle coke spherical electrodes were fabricated for the first time using the sintering method. With DSA as the anode, nickel foam as the cathode and the spherical electrodes as the particle electrodes, a three-dimensional (3D) electro-Fenton system was constructed to treat coking wastewater. Using the chemical oxygen demand (COD) removal efficiency of coking wastewater as an indicator of electrode performance, the optimal conditions for particle electrode preparation were determined by single-factor experiments as consisting of a 4:1 catalyst-to-binder ratio, Fe2+ loading for the preparation of the particle electrodes of 2.5%, a particle size of 5.5 ± 0.5 mm, and a sintering temperature of 400 °C. Response surface methodology was applied to model and optimise the 3D electro-Fenton process for treating coking wastewater. Under the optimal conditions of an electrode spacing of 5 cm, applied voltage of 11.15 V, initial pH of 2.62, and particle electrode dosing of 12.23 g L-1, the removal rates of COD, NH3-N, NO3--N, total nitrogen, colour, and UV254 were 87.5%, 100%, 72.2%, 84.8%, 95%, and 72.4%, respectively. Spectral analysis revealed that the 3D electro-Fenton system strongly degraded coking wastewater, causing decomposition of large molecules of organic compounds and residuals primarily consisting of olefins and alkanes. Because the prepared particle electrodes exhibited stable physical and chemical structure, they have great potential for engineering applications due to their resistance to water flow erosion, stable catalytic reaction activity, and reusability.

Joint effects of polycyclic aromatic hydrocarbons, smoking, and XPC polymorphisms on damage in exon 2 of KRAS gene among young coke oven workers.

Genetic polymorphisms may contribute to individual susceptibility to DNA damage induced by environmental exposure. In this study, we evaluate the effects of co-exposure to PAHs, smoking and XPC polymorphisms, alone or combined, on damage in exons. A total of 288 healthy male coke oven workers were enrolled into this study, and urinary 1-hydroxypyrene (1-OH-Pyr) was detected. Base modification in exons of KRAS and BRAF gene, and polymorphisms of XPC were determined in plasma by real-time PCR. We observed 1-OH-Pyr was positively related to damage in exon 2 of KRAS (KRAS-2) and in exon 15 of BRAF (BRAF-15), respectively, and KRAS-2 and BRAF-15 were significantly associated with increased 1-OH-Pyr. A stratified analysis found 1-OH-Pyr was significantly associated with KRAS-2 in both smokers and non-smokers, while 1-OH-Pyr was significantly associated with BRAF-15 only in smokers. Additionally, individuals carrying both rs2228001 G-allele (GG+GT) and rs3731055 GG homozygote (GG) genotype appeared to have more significant effect on KRAS-2. The high levels of 1-OH-Pyr were associated with KRAS-2 only in rs2228001 GG+GT genotype carriers and the high levels of 1-OH-Pyr were associated with KRAS-2 only in rs3731055 GG genotype carriers and the most severe KRAS-2 was observed among subjects carrying all four of the above risk factors. Our findings indicated the co-exposure effect of PAHs and smoking could increase the risk of KRAS-2 by a mechanism partly involving XPC polymorphisms.

Urinary polycyclic aromatic hydrocarbon metabolites, plasma p-tau231 and mild cognitive impairment in coke oven workers.

BACKGROUND: As a group of environmental pollutants, polycyclic aromatic hydrocarbons (PAHs) may be neurotoxic，especially in high-exposure occupational populations. However, the effect of PAHs on mild cognitive impairment (MCI) is still unclear. OBJECTIVE: We aimed to investigate the relationship between PAH metabolites and MCI and to explore whether plasma p-tau231 can be used as a potential biomarker to reflect MCI in coke oven workers. METHOD: A total of 330 workers were recruited from a coke oven plant as the exposure group, and 234 workers were recruited from a water treatment plant as the control group. The concentrations of eleven PAH metabolites and plasma p-tau231 were determined by high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) and ELISA. Cognitive function was measured by the Montreal Cognitive Assessment (MoCA) questionnaire. A multivariate logistic regression model and multiple linear regression model were used to analyze the associations of urinary PAH metabolites with the detection rate of MCI, MoCA scores and plasma p-tau231. The dose-response relationships were evaluated using restricted cubic spline models. RESULTS: We found 146 MCI-positive workers in coke oven plant (44.24%), and 69 MCI-positive workers in water treatment plant (29.49%). In addition, the urinary sum of PAH metabolites (Æ©-OH PAHs) was significantly associated with MCI (OR, 1.371; 95% CI:1.102-1.705). Each one-unit increase in ln-transformed Æ©-OH PAHs was associated with a 0.429 decrease in the sum of MoCA, a 0.281 reduction in the visuospatial/executive function and a 9.416 increase in the level of plasma P-Tau231. We found a negative association between plasma P-Tau231 and visuospatial/executive function (ß = -0.007, 95% CI: -0.011, -0.003). CONCLUSION: Our data indicated that urinary Æ©-OH PAHs levels of workers were positively associated with MCI and the level of plasma P-Tau231.