Nitrogen mustard (NM) is a vesicant, and the respiratory tract is one of its primary target organs. The recovery following NM exposure is protracted. Despite the existence of numerous theories regarding the toxic effects of NM, but to date, no studies have investigated the global cellular response profiles across distinct phases after NM exposure. Herein, we examined alterations in pulmonary function in mice before and after NM exposure, characterized the biological changes in human bronchial epithelial cells (HBEs) during acute NM exposure and the subsequent post-exposure recovery phase, and further analyzed the impact of p97 deficiency on cell injury.Following acute NM exposure, the expiratory time and total respiratory cycle time were prolonged in mice, whereas the expiratory flow at 50% of tidal volume (EF50) and alveolar volume were reduced. NM rapidly perturbs nucleic acid-associated biological processes within the nucleus, including the cell cycle, chromatin dynamics, mitosis, and RNA processing and splicing, with concomitant upregulation of the expression of relevant proteins. Acute NM exposure for 1 h exerted no effect on total p97 expression level, but promoted the accumulation of p97 in the cytoplasm. In contrast, nuclear p97 expression was increased at 24 h after NM removal. Although p97 deficiency exerted minimal effects on cellular stress responses during the acute exposure phase, it disrupted intracellular material transport, elicited a tendency toward the suppression of nuclear protein expression, and impeded the recovery process after the termination of NM exposure. P97 deficiency primarily repressed the expression of nucleoporins and histones, and inhibited aerobic respiration during the cellular recovery phase.Collectively, these findings suggest that the perturbation of nucleic acid-associated biological processes constitutes the initial and critical event underlying the respiratory toxicity of NM. Furthermore, p97 deficiency impairs material transport, small-molecule metabolism, and mitochondrial function, and prolongs the recovery time in the aftermath of NM exposure.

Prenatal exposure to fine particulate matter (PM2.5) has been associated to childhood atopic dermatitis (AD), but the critical exposure window and the role of maternal inflammatory pathways remain unclear. We analyzed 4048 mother-child pairs from two prospective birth cohorts in Chongqing (PRHBIC & CSBC, 2014-2021). Trimester-specific mean exposure to PM2.5 components (BC, OM, SO42 -, NO3-, NH4+) were assigned to residential address. Systemic low-grade inflammation was quantified by trimester neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation index (SII). Physician-diagnosed AD up to age 3 was the outcome. We used generalized linear models, weighted quantile sum models (WQS), interaction analyses (additive & multiplicative) and mediation analyses. Of 4048 children, 1554 (38.3%) developed AD. Associations were strongest for first-trimester: SO4²⁻ showed the largest adjusted effect (OR per IQR = 1.187; 95% CI 1.080-1.304). WQS indicated a positive association for the PM2.5 component mixure (OR = 1.023; 95% CI: 1.009-1.039), with OM receiving the largest WQS weight among components. Maternal NLR and SII were positively associated with first-trimester PM2.5 components and partially mediated the pollutant-AD association. Additionally, SII demonstrated significant effect modification on the additive scale (RERI: 0.41-0.55; AP: 0.26-0.29). Early pregnancy represents a critical window for PM2.5-related offspring AD risk in our study. Reducing air pollution and modulating maternal inflammatory status during the first trimester may serve as dual strategies for AD prevention.

BACKGROUND:Hypertensive disorders of pregnancy (HDP) are a leading cause of maternal death. While ambient temperature and air pollution have each been linked to HDP, evidence regarding their combined effects and the modifying roles of relative humidity and green space remains limited. OBJECTIVE:To examine whether ambient temperature modifies the association between fine particulate matter (PM2.5) exposure and HDP risk, and to assess the interactive effects of PM2.5, relative humidity, and green space in Chongqing, China. METHODS:We conducted a cross-sectional study including 48,160 pregnant women who delivered in a hospital in Chongqing between January 2021 and December 2023. Environmental data on temperature, PM2.5, relative humidity, and green space were obtained from local monitoring stations. Generalized linear mixed models were applied to estimate associations between environmental exposures and HDP, adjusting for potential covariates and incorporating interaction terms among PM2.5, relative humidity, and green space. RESULTS:Elevated temperature exposure potentiated the association between PM2.5 and HDP, with an adjusted odds ratio (aOR) of 1.11 (95%CI: 1.02-1.20). After including interaction terms, the effect remained pronounced under high-temperature conditions, with aORs of 1.10 (95%CI: 1.07-1.15) in the heat-exposure group and 1.08 (95%CI: 1.02-1.13) in the cold-exposure group. The first trimester was identified as a critical exposure window for PM2.5-related HDP risk. CONCLUSION:In Chongqing, high temperature exacerbates the association between PM2.5 exposure and the incidence of HDP. The interactions among green space, relative humidity, and PM2.5 further modify this relationship, highlighting the complex interplay of environmental factors in the etiology of HDP.

Whether the number and quality of births have been changed after the COVID-19 pandemic remains unclear. We aimed to examine whether the number of births, gestation weeks, and birth weight changed after COVID-19 in Chongqing, the largest municipality by area in China. Birth registration data of Chongqing from January 2015 to July 2022 were used to compare the quantity and quality (gestation week, preterm birth rate, birth weight, low birth weight rate) of births before and after the pandemic by interrupted time series analysis by autoregressive average moving models (ARIMA) and linear models of interrupted time series analysis (ITSA). October 2020, which was nine months after the onset of the first-wase of COVID-19 pandemic, was designated as the cut point to account for the gestation duration. Data from the Chongqing Preconception Reproductive Health and Birth Outcome Cohort were then utilized to analyze the temporal changes in pre-pregnancy body mass index (BMI) among reproductive-age women before (January 2019 to January 2020) and after the pandemic (March 2020 to March 2023). There were 2,099,898 birth records included. Before the pandemic, there were monthly declining trends in the number of births (β=-100.44, 95

Dyslexia is a common neurodevelopmental disorder, but its underlying mechanisms remain unclear. Based on the Tongji Reading Environment and Dyslexia (READ) project, this study aimed to evaluate the associations of solute carrier (SLC) gene polymorphisms and heavy metal exposure with dyslexia in Chinese children and to further explore gene-environment interactions. Dyslexia was screened using the Dyslexia Checklist for Chinese Children and the Pupil Rating Scale-Revised Screening. Bioinformatics strategy was used to identify functional SLC-related SNPs, and genotyping was performed using the ASAMD array. Urinary heavy metal concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS). Five functional SLC-related SNPs were associated with dyslexia risk, and SLC22A3 rs555754 remained significant after multiple-testing correction (OR = 1.37; 95% CI, 1.11-1.69; PFDR = 0.045). In addition, higher urinary barium and strontium levels were associated with increased dyslexia risk, and barium showed a U-shaped nonlinear association with dyslexia. In gene-environment analyses, a multiplicative interaction was observed between barium and SLC18A2 rs2619095 (Pmul = 0.041). Compared with children with low barium exposure and the rs2619095 CC genotype, those with high barium exposure and the CA/AA genotype had 2.41-fold higher odds of dyslexia (OR = 2.41; 95% CI, 1.35-4.29). Overall, this is the first study to link SLC polymorphisms and multiple metal exposures to dyslexia in children. Our findings suggest that genetic and environmental factors may jointly influence dyslexia risk, providing new epidemiologic evidence and clues to advance understanding of dyslexia pathogenesis.

Objective To investigate the associations between body mass index(BMI)trajectories in early and mid-pregnancy and preterm birth,to examine the mediating effects of gestational diabetes mellitus(GDM)and inflammatory markers,and to provide evidence for early prevention and intervention of preterm birth.Methods A prospective cohort study was conducted and 1 221 pregnant women who delivered babies at Chongqing Maternal and Child Health Hospital between 2018 to 2021 were included.Group-based trajectory modeling was used to identify BMI trajectories in early and mid-pregnancy.Logistic regression and causal mediation analyses were performed to evaluate the mediating effects of GDM and inflammatory factors in the associations between BMI trajectories and preterm birth.Results TThree BMI trajectories were identified,and the participants were categorized accordingly into Group 1(48.98%),Group 2(38.41%),and Group 3(12.61%).Group 2 demonstrated a trajectory similar in shape to that of Group 1,with an overall level between those of Group 1 and Group 3.Participants in Group 3 were in the obese range in early pregnancy,with their BMI decreasing slightly along with the progression of pregnancy and stabilizing and then rising slightly in mid-pregnancy.After adjusting for confounders,Group 3 showed higher risks of preterm birth,which were 3.1 times those of Group 1(odds ratio[OR]=3.10,95%CI:1.59-6.06).Additionally,white blood cell count and monocyte percentage significantly mediated this association,with proportion eliminated of 0.5%and 5.1%,respectively.No mediating effect of GDM was observed.Conclusion Pregnant women with higher BMI during early and mid-pregnancy exhibit a significantly increased risk of preterm birth.White blood cell count and monocyte percentage may serve as key inflammatory mediators linking this association while the mediating effect of GDM is not found.

BackgroundPreterm birth (PTB) is a global health concern. The combined effects of prenatal PM2.5 and heavy metal exposures on PTB risk remain unclear.MethodsA nested case-control study included 111 PTB cases and 124 controls from Chongqing. Maternal blood concentrations of 18 trace elements were measured in mid-pregnancy. Fine particulate matter (PM2.5) exposure data were obtained from the Tracking Air Pollution in China (TAP). Residential addresses were geocoded and linked to these exposure estimates. Logistic regression, weighted quantile sum (WQS), grouped WQS (GWQS), and bayesian kernel machine regression (BKMR) models were used to evaluate individual, mixture and interaction effects.ResultsHigher PM2.5 exposure during the second trimester and early-to-mid pregnancy was associated with increased PTB risk. Cadmium, selenium, and zinc were positively associated with PTB, whereas lithium and nickel were inversely associated. WQS models indicated the mixture was associated with elevated PTB risk (OR: 2.01, 95% CI: 1.09, 3.71), with PM2.5 contributing the largest weight, lithium and nickel were inversely associated (OR: 0.36, 95% CI: 0.18, 0.74). GWQS models showed that PM2.5 (OR: 2.24, 95% CI: 1.68, 3.07) and essential trace elements (ETE) (OR: 2.32, 95% CI: 1.60, 3.44) positively associated with PTB, whereas conditionally essential trace elements (CTE) were inversely associated (OR: 0.37, 95% CI: 0.23, 0.59). Seven-group GWQS analyses suggested potential interaction between PM2.5 and ETE (OR: 4.44, 95% CI: 2.33, 9.10) and inverse associations with CTE. BKMR revealed nonlinear mixture effects and a non-monotonic effect of lithium.ConclusionPregnancy exposure to PM2.5 and heavy metal mixtures were associated PTB risk, with evidence of complex and potentially interactive associations. These findings highlight the importance of integrated assessments of multiple environmental exposures and targeted public health strategies to reduce maternal and child health risks.

Exposure to fine particulate matter (PM2.5) has been associated with impaired semen quality, but the potential mitigating role of residential greenness remains unclear. We conducted a hospital-based prospective cohort study of 3770 Chinese men who underwent 4847 semen examinationin in Chongqing, China (2018-2023). Exposure to PM2.5 and its components (SO42-, NO3-, NH4+, OM, BC) was estimated for the 0-90 days preceding semen collection, while residential greenness was assessed using satellite-derived normalized difference vegetation index (NDVI) over the same period. Semen quality parameters including progressive motility, non-progressive motility, total motility, sperm concentration, total sperm count, and viability, were assessed according to WHO 5th edition guidelines. Linear mixed-effects models were used to examine associations between environmental exposures and semen quality and their interactions. Higher exposure to PM2.5 and its components was associated with poorer semen quality, including reduced progressive motility, sperm concentration, sperm count, sperm viability, and total motility. For instance, per IQR increase in PM2.5 was associated with a 2.0% decrease in progressive motility (-3.7%, -0.3%) and a reduction in total sperm count of 0.108 million sperm (-0.160, -0.056). In contrast, higher residential greenness was positively associated with total sperm count. Significant interactions were observed between greenness and PM2.5 or SO42- for progressive and total sperm motility, with higher greenness mitigating adverse effects, particularly at lower SO42- levels. The observed associations varied across age, BMI, education levels, adverse lifestyle factors, and season. These findings highlight the potential role of urban green spaces in protecting male reproductive health.

Spontaneous abortion (SAB), a significant adverse pregnancy outcome, affects up to 30 % of pregnancies. While recent studies have demonstrated the harmful effects of environmental fine particulate matter (PM2.5) pollution on pregnancy outcomes, the specific contributions of individual PM2.5 components to the risk of SAB remain unclear. This case-control study examines the impact of short-term exposure to PM2.5 and its chemical components-black carbon (BC), organic matter (OM), sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+)-on the risk of SAB in Chongqing, China, from 2020 to 2023. Data from 1661 SAB cases were analyzed, with exposure to PM2.5 and its components estimated using address-based inverse distance weighting. Conditional logistic regression models revealed significant associations between SAB risk and per inter quartile range (IQR) increases in PM2.5 (Odds Ratio [OR]: 1.33, 95 % Confidence Interval [CI]: 1.17-1.50), BC (OR: 1.31, 95 % CI: 1.17-1.46), OM (OR: 1.38, 95 % CI: 1.22-1.56), and NO3-(OR: 1.25, 95 % CI: 1.08-1.45). Multi-pollutant analysis identified OM as the largest contributor to joint effects, accounting for 76.5 % of the total. Distributed lag non-linear models highlighted specific temporal susceptibility windows, showing lagged effects of PM2.5, BC, OM, and NO3- within the 28 days before conception. These findings underscore the role of PM2.5 and its components, particularly OM, in increasing SAB risk and emphasize the importance of targeting critical exposure periods in preventive strategies.

BACKGROUND:Little is known regarding the shared genetic architecture underlying the phenotypic associations between depression and preterm birth (PTB). We aim to investigate the genetic overlap and causality of depression with PTB. METHODS:Leveraging summary statistics from the largest genome-wide association studies for broad depression (Ntotal = 807,533), major depression (Ntotal = 173,005), bipolar disorder (Ntotal = 414,466), and PTB (Ntotal = 226,330), we conducted a large-scale genome-wide cross-trait analysis to assess global and local genetic correlations, identify pleiotropic loci, and infer potential causal relationships. RESULTS:Positive genetic correlations were observed between PTB and broad depression (rg = 0.242), major depression (rg = 0.236), and bipolar disorder (rg = 0.133) using the linkage disequilibrium score regression, which were further verified by the genetic covariance analyzer. Local genetic correlation was identified at chromosome 11q22.3 (harbors NCAM1-TTC12-ANKK1-DRD2) for PTB with depression. Cross-trait meta-analysis identified two loci shared between PTB and broad depression, two loci shared with major depression, and five loci shared with bipolar disorder, among which three were novel (rs7813444, rs3132948 and rs9273363). Mendelian randomization demonstrated a significantly increased risk of PTB for genetic liability to broad depression (odds ratio [OR]=1.30; 95% confidence interval [CI]: 1.11-1.52) and major depression (OR=1.27; 95%CI: 1.08-1.49), and the estimates remained significant across the sensitivity analyses. CONCLUSIONS:Our findings demonstrate an intrinsic link underlying depression and PTB and shed novel light on the biological mechanisms, highlighting an important role of early screening and effective intervention of depression in PTB prevention, and may provide novel treatment strategies for both diseases.

Background The pathogenesis of chronic migraine remains to be explored. Studies have confirmed that the incidence of chronic migraine is significantly higher in female patients than in male patients. The Estrogen receptor GPER is a G protein-coupled receptor and a member of the estrogen-related receptor family, which has been proven to regulate inflammation. Therefore, this study explores the exact role of the GPER receptor in chronic migraine and its mechanisms. Method Chronic migraine models were established by repeatedly stimulating the lateral ventricle with inflammatory soup. Mechanical and thermal pain thresholds were evaluated using von Frey filaments and radiant heat. The mRNA and protein expression levels of dopamine GPER receptor were analyzed by qRT-PCR and western blotting. Immunofluorescence was used to observe the co-localization of dopamine GPER and microglial Iba-1, as well as SP1 and microglial Iba-1. A GPER receptor antagonist (G15) and receptor agonist (G1), an SP1 inhibitor (AV37193-100UG), and an NLRP3 antagonist (MCC950) were used to investigate the specific mechanisms. Serum samples were collected from chronic migraine patients aged 18 to 74 years and 9 male controls without a family history of chronic migraine. The levels of 17β-estradiol and testosterone in the serum of the two groups were compared. Result Inflammatory soup stimulation significantly reduced the pain threshold in rats, accompanied by a decrease in the expression of GPER receptor at the TNC site, an increase in the expression of nuclear transcription factor SP1, and NLRP3 in microglia. In the TNC, GPER and SP1 were co-localized with microglia, and the antagonism of GPER mediated an increase in the nuclear translocation of SP1, aggravating the pain hyperalgesia in CM rats, which was reversed by NLRP3 activation in CM rats. Finally, the serum level of 17β-estradiol in male patients with chronic migraine was higher than that in the control group. Conclusion GPER may be involved in the pathogenesis of chronic migraine in rats by mediating the nuclear translocation of SP1 and regulating the transcriptional level of NLRP3 and central sensitization. GPER may be a valuable candidate for the treatment of chronic migraine.

BACKGROUND:Previous observational studies investigating the association between shift work and male fecundity employed retrospective designs and reported inconsistent findings. The distinction between rotating and fixed shift work has been noticed but not often taken into consideration in the field of reproductive health. Whether semen parameters played a role in this relationship was also unclear. OBJECTIVE:This study aimed to prospectively evaluate the association between male rotating shift work and achieving a successful pregnancy, and to assess the contribution of semen parameters to this relationship. MATERIALS AND METHODS:Men reported their work type (rotating shift workers, fixed day workers, and fixed shift workers) and seven semen parameters (semen volume, sperm concentration, total sperm count, progressive motility, total motility, vitality, and normal morphology) were measured. Participants were contacted every 3 months for pregnancy status for up to 24 months or until conception. The rates of achieving a successful pregnancy within 1 year and 2 years were calculated to estimate male fecundity. Cox regression and linear regression were applied to compare the hazard of achieving a pregnancy within 1/2 year and semen parameters among rotating shift workers, fixed day workers, and fixed shift workers. Mediation analysis was applied to examine the contributions of semen parameters to the shiftwork-fecundity association. RESULTS:(1) After adjusting confounders, rotating shift workers had a 16% (HR = 0.84, 95% CI, 0.70-0.99, p = 0.04) and 14% (HR = 0.86, 95% CI, 0.74-1.01, p = 0.06) lower hazard of achieving a pregnancy within 1 year and 2 years, respectively, compared to fixed day workers. (2) Of the seven semen parameters, the rotating shift workers were significantly associated with lower sperm concentration (β = -10.77%, 95% CI, -18.89% to -2.55%, p = 0.01), total sperm count (β = -11.63%, 95% CI, -21.25% to -2.02%, p = 0.02), and vitality (β = -3.86%, 95% CI, -7.00% to -0.72%, p = 0.02) compared to the fixed day workers. No significant difference was found between fixed day workers and fixed shift workers. (3) Sperm concentration accounted for 33.46% and 31.12% of the total effect of the relationship between rotating shift work and lower hazard of achieving a pregnancy within 1 and 2 years. Vitality also mediated this association by 30.79% and 23.59%, respectively. CONCLUSIONS:Male rotating shift work was associated with reduced fecundity, primarily attributed to reduced sperm concentration and vitality. The study emphasizes the need for occupational protection and provision of medical care for male workers with rotating shifts.

Backgrounds: There are multiple risk factors for preterm birth (PTB), one of the most important of which is mood disorders during pregnancy. We aimed to comprehensively investigate the association of both total mental health concerns and ten specific psychiatric symptoms with PTB risk. Methods: A cohort study was performed consisting of 25,175 pregnant women who participated in Women and Children's Hospital of Chongqing Medical University between 2020 and 2022. The Symptom Checklist 90 (SCL-90) was utilized to assess the psychiatric symptoms. Multivariable or multinomial logistic regression was applied to investigate mental health concerns associated with risk of PTB or its different clinical sub-categories, respectively. Sensitivity analyses were further performed to validate the results. Results: 8336 women who met the inclusion criteria were included; of these, 547 (6.6 %) had preterm deliveries, and 2542 (30.5 %) had mental health concerns. Compared with women with healthy minds, women with total mental health concerns had a 29.0 % higher risk of overall PTB (OR = 1.28, 95%CI = 1.07-1.54), medical-induced PTB (OR = 1.49, 95%CI = 1.05-2.13) and spontaneous PTB with premature rupture of membranes (OR = 1.33, 95%CI = 1.01-1.74). As to the specific psychological symptoms, hostility pregnant women had a 55.0 % higher risk of PTB (OR = 1.55, 95%CI = 1.14-2.11). Similar results were observed in most of the sensitivity analyses. Limitations: This is a single-center study, thus the extrapolation of the results may be limited. Conclusions: Pregnant women with mental health symptoms, especially hostility, have an increased risk of PTB. The findings underscore that integrating mental health services into routine maternal care may be a strategy to prevent PTB.

BACKGROUND:Placental abruption, a rare disorder of unclear etiology, lacks evidence to illustrate its relationship with exposure to air pollution and temperature. OBJECTIVE:This study aimed to investigate the association between exposure to ambient pollutants and temperatures and placental abruption to identify susceptible time windows and subpopulations. METHODS:A nested case-control study was based on a live birth registration database in Chongqing, the largest Chinese municipality in China, from 2018 to 2022. The placental abruption cases were each matched with four controls by maternal age at delivery, gestational week, gravidity, parity, and delivery date. Six ambient pollutants [particulate matter (PM) with aerodynamic diameter ≤2.5μm (PM2.5), PM with aerodynamic diameter ≤10μm (PM10), NO2, CO, O3, and SO2] and temperature were estimated using machine learning algorithms. A conditional logistic regression model analyzed associations of exposure to air pollution and temperature with placental abruption in five time windows (prepregnancy, the entire pregnancy, and each of the 3 trimesters). Stratification analyses were applied to examine potential modifiers including gravidity, parity, mothers' residential area (urban/rural), pandemic experience, and delivery season. RESULTS:After data quality control, 798 cases were identified and matched with 3,192 controls. An exposure relationship was identified between NO2 during the pregnancy period and placental abruption (p<0.001). In comparison with the first quartile level of NO2, the odds ratios (ORs) of abruption associated with exposure to the second, third, and fourth quartile levels of NO2 were 1.42 [95% confidence interval (CI): 1.03, 1.96], 1.90 (95% CI: 1.30, 2.76), and 2.27 (95% CI: 1.39, 3.71), respectively. The association for NO2 exposure existed in the 3 trimesters but not prepregnancy. Exposure to locally extreme low temperatures (<fifth percentile) in the third trimester was associated with increased risks of abruption (OR=3.68; 95% CI: 1.67, 8.08) in comparison with locally moderate temperatures (25th-75th percentile). Stratified analysis showed no statistical significances within the effect modifiers. DISCUSSION:Based on a large-scale live birth record, the study suggested that exposure to air pollutants, mainly NO2, during pregnancy may be a substantial risk factor for placental abruption. https://doi.org/10.1289/EHP14714.

Nitrogen mustard (NM) is a vesicant agent with potent toxic effects on various tissues. Numerous theories have been proposed to explain its toxic mechanisms, yet research on the interconnections among these theories is lacking. This study focuses on analyzing the characteristics of genes involved in NM-induced bronchial injury within the Comparative Toxicogenomics Database (CTD). Subsequently, based on the CTD, we compared and analyzed the acute exposure and delayed changes following exposure in 16HBE cells. The injury processes caused by NM to bronchial and skin tissues are similar, primarily involving metabolism and regulation of nuclear constituents and inflammatory responses within the cellular matrix. During the acute exposure phase, NM rapidly induces nuclear stress, with the JUN family at the core of regulating metabolic and nucleic acid activities, and various nuclear binding proteins exhibit abnormalities. Delayed reactions following acute exposure are primarily centered in the cytoplasmic region, with diverse reaction types, including oxidative stress and responses to exogenous stimuli. Abnormalities in the activity of multiple cellular matrix enzymes are observed, with a relatively even involvement of various stress responses. Communication between the nucleus and cytoplasm is extreme active during the injury, and the content of the communication changes over time. These results suggest a temporal sequence in which NM causes chromatin damage and mediates cytoplasmic stress responses. In prevention and first aid, rapid DNA repair should be the primary focus, while subsequent treatment after acute exposure should focus more on delayed inflammatory and oxidative stress responses.

Abstract Background Preterm birth (PTB) is an important predictor of perinatal morbidity and mortality. Previous researches have reported a correlation between air pollution and an increased risk of preterm birth. However, the specific relationship between short-term and long-term exposure to carbon monoxide (CO) and preterm birth remains less explored. Methods A population-based study was conducted among 515,498 pregnant women in Chongqing, China, to assess short-term and long-term effects of CO on preterm and very preterm births. Generalized additive models (GAM) were applied to evaluate short-term effects, and exposure-response correlation curves were plotted after adjusting for confounding factors. Hazard ratios (HR) and 95% confidence intervals (CI) were calculated using COX proportional hazard models to estimate the long-term effect. Results The daily incidence of preterm and very preterm birth was 5.99% and 0.41%, respectively. A positive association between a 100 µg/m³ increase in CO and PTB was observed at lag 0–3 days and 12–21 days, with a maximum relative risk (RR) of 1.021(95%CI: 1.001–1.043). The exposure-response curves (lag 0 day) revealed a rapid increase in PTB due to CO. Regarding long-term exposure, positive associations were found between a 100 µg/m3 CO increase for each trimester(Model 2 for trimester 1: HR = 1.054, 95%CI: 1.048–1.060; Model 2 for trimester 2: HR = 1.066, 95%CI: 1.060–1.073; Model 2 for trimester 3: HR = 1.007, 95%CI: 1.001–1.013; Model 2 for entire pregnancy: HR = 1.080, 95%CI: 1.073–1.088) and higher HRs of very preterm birth. Multiplicative interactions between air pollution and CO on the risk of preterm and very preterm birth were detected (P- interaction<0.05). Conclusions Our findings suggest that short-term exposure to low levels of CO may have protective effects against preterm birth, while long-term exposure to low concentrations of CO may reduce the risk of both preterm and very preterm birth. Moreover, our study indicated that very preterm birth is more susceptible to the influence of long-term exposure to CO during pregnancy, with acute CO exposure exhibiting a greater impact on preterm birth. It is imperative for pregnant women to minimize exposure to ambient air pollutants.

Objective To study the relationship of urinary total arsenic exposure level with sperm quality and sex hormone levels in young male population, and evaluate the potential impact of background arsenic exposure on parameters of sperm quality and sex hormone levels in Chongqing. Methods Generalized additive model and recursive algorithm were used to analyze the correlation of the baseline urine arsenic concentration with semen parameters and sex hormone levels in 703 male college students volunteers（18～22 years old） in the cohort of Chongqing college students constructed in 2013-2015. The inflection point of the nonlinear relationship was explored, and the threshold effect of arsenic exposure was analyzed. The median of urinary arsenic in this study was compared with the data from other reports at home and abroad. Results There was a nonlinear relationship of urine arsenic level with sperm concentration, sperm total number, sperm DNA fragment index, and levels of prolactin, follicle-stimulating hormone and progesterone. Further threshold effect analysis showed that there were inflection points of urine arsenic concentration with the above indicators, and the key points were 15.17, 14.17, 50.97, 57.51, 11.36, and 70.44 μg/L, respectively（Log-likelihood ratio test P＜0.05）. Compared with relevant literature, the urine arsenic level was at a relatively lower level in this cohort population. Conclusion Compared with some regions at home and abroad, the background urine arsenic level of this study population is quite lower, and significant correlation is found in the background level with the decline of sperm quality parameters and changes in sex hormone levels.

Introduction There have been many researches done on the association between maternal exposure to ambient air pollution and adverse pregnancy outcomes, but few studies related to very low birth weight (VLBW). This study thus explores the association between maternal exposure to ambient air pollutants and the risk of VLBW, and estimates the sensitive exposure time window. Methods A retrospective cohort study analyzed in Chongqing, China, during 2015–2020. The Generalized Additive Model were applied to estimate exposures for each participant during each trimester and the entire pregnancy period. Results For each 10 μg/m 3 increase in PM 2.5 during pregnancy, the relative risk of VLBW increased on the first trimester, with RR = 1.100 (95% CI: 1.012, 1.195) in the single-pollutant model. Similarly, for each 10 μg/m 3 increase in PM 10 , there was a 12.9% (RR = 1.129, 95% CI: 1.055, 1.209) increase for VLBW on the first trimester in the single-pollutant model, and an 11.5% (RR = 1.115, 95% CI: 1.024, 1.213) increase in the multi-pollutant model, respectively. The first and second trimester exposures of NO 2 were found to have statistically significant RR values for VLBW. The RR values on the first trimester were 1.131 (95% CI: 1.037, 1.233) and 1.112 (95% CI: 1.015, 1.218) in the single-pollutant model and multi-pollutant model, respectively; The RR values on the second trimester were 1.129 (95% CI: 1.027, 1.241) and 1.146 (95% CI: 1.038, 1.265) in the single-pollutant model and multi-pollutant model, respectively. The RR of O3 exposure for VLBW on the entire trimester was 1.076 (95% CI: 1.010–1.146), and on the second trimester was 1.078 (95% CI: 1:016, 1.144) in the single-pollutant model. Conclusion This study indicates that maternal exposure to high levels of PM 2.5 , PM 10 , NO 2 , and O 3 during pregnancy may increase the risk of very low birth weight, especially for exposure on the first and second trimester. Reducing the risk of early maternal exposure to ambient air pollution is thus necessary for pregnant women.

Accumulating evidence suggested that the risk of preterm births (PTBs) following prenatal exposure to air pollution was inconclusive. The aim of this study is to investigate the relationship between air pollution exposure in the days before delivery and PTB and assess the threshold effect of short-term prenatal exposure to air pollution on PTB. This study collected data including meteorological factors, air pollutants, and information in Birth Certificate System from 9 districts during 2015–2020 in Chongqing, China. Generalized additive models (GAMs) with the distributed lag non-linear models were conducted to assess the acute impact of air pollutants on the daily counts of PTB, after controlling for potential confounding factors. We observed that PM2.5 was related to increased occurrence of PTB on lag 0–3 and lag 10–21 days, with the strongest on the first day (RR = 1.017, 95