The associations between ambient fine particulate matter (PM2.5) and its components (sulfate, ammonium, nitrate, organic matter, and black carbon) and the risk of preeclampsia remain unclear, particularly in high-altitude regions where evidence is limited. This study aimed to provide novel insights into this issue. Lanzhou, China, was selected as a representative high-altitude city, and data from 169,484 women who delivered between 2016 and 2021 were included. Logistic regression models were used to evaluate the associations between individual exposure to PM2.5 and its components and the risk of preeclampsia. The joint associations and the contribution weights of each component were further assessed using quantile g-computation. Additionally, distributed lag nonlinear models were applied to identify potential lagged associations. The results indicated that individual exposures to PM2.5 and its components during the entire exposure period, the preconception period, and the first trimester were significantly associated with an increased risk of preeclampsia (p < 0.05). Mixed exposures to PM2.5 components during the entire exposure period and the preconception period were also significantly associated with an increased risk of preeclampsia (p < 0.05), with black carbon (0.43) and ammonium (0.48) showing the highest positive weights, respectively. The strongest associations between high-level pollutant exposure and preeclampsia risk were observed during the preconception period or the first trimester. These findings suggest that public health interventions should target key PM2.5 components and critical exposure windows to mitigate the risk of preeclampsia in high-altitude regions.

PM2.5 and its constituents are linked to various comorbidities and complications during pregnancy. However, evidence remains limited regarding the association of total PM2.5 mass and PM2.5 constituents with premature rupture of membranes (PROM) in twin pregnancies. Accordingly, contributing new insights to this field is of significant value. In this study, we employed logistic regression, restricted cubic spline regression, weighted quantile sum, quantile g-computation, Bayesian kernel machine regression, and subgroup analyses to quantify the individual and joint associations of PM2.5 and its constituents with the risk of PROM in twin pregnancies, identify sensitive exposure windows during pregnancy, and explore potential effect modifiers. We found that the risk of PROM in twin pregnancies was positively associated with total PM2.5 mass and PM2.5 constituents, with stronger associations observed in trimester 1. Co-exposure to NH4+, NO3-, SO42-, BC, and OM was also linked to an elevated risk of PROM, with NO3-, SO42-, and OM identified as the most influential constituents. Similarly, trimester 1 was also identified as a sensitive exposure window during pregnancy for co-exposure to NH4+, NO3-, SO42-, BC, and OM. In addition, PM2.5-related PROM risk was higher among pregnant women with high education levels and advanced maternal age. Our findings suggest that the risk of PROM in twin pregnancies is associated with PM2.5 exposure during pregnancy, and highlight the necessity for developing targeted mitigation strategies, especially for trimester 1 and pregnant women with high education levels and advanced maternal age.

Total PM2.5 mass has been shown to be associated with mumps. However, the individual and joint associations of PM2.5 components with mumps and the importance of each PM2.5 component remain unclear. To our knowledge, this ecological study is the first to investigate the associations of PM2.5 components with mumps. We collected the monthly mumps incidence in Northwest China from 2013 to 2019 to investigate the individual and joint effects of PM2.5 components on mumps using geographical probes, quantile g-computation (qgcomp), and Bayesian kernel-machine regression (BKMR) models. We found that sulfate (SO42-) and black carbon (BC) were associated with mumps, and SO42- (weight: 0.143) and organic matter (OM) (weight: 0.857) were positively correlated to mumps according to the qgcomp results. BKMR revealed that BC and OM were the dominant factors for the increasing monthly mumps incidence. The joint associations of PM2.5 components with mumps were positive at the high concentrations, and the single-pollutant models suggested that the individual associations of BC and OM with mumps were positive. Our evidence emphasizes that targeted control of anthropogenic sources of PM2.5 components (especially BC and OM) can help mitigate the monthly mumps incidence.

Climate change is intensifying the frequency and severity of extreme heat events. While the impact of temperature on respiratory health is well-documented, the synergistic effects of combined heat and humidity are less clear, especially for children, a population with heightened vulnerability. This study investigates the differential impacts of humid heat (measured by Wet-Bulb Globe Temperature, WBGT) and temperature alone on paediatric asthma emergency department visits (EDVs) in Shanghai, China, and projects the future disease burden under climate change. We conducted a time-series analysis of 42,604 paediatric asthma EDVs recorded across 66 hospitals in Shanghai during the summer seasons of 2016–2018. Distributed lag non-linear models were used to quantify the association between daily EDVs and both WBGT and temperature. We projected future humid-heat-related asthma burden through 2099 under four Shared Socioeconomic Pathway scenarios (SSP1-2.6, SSP2-4.5, SSP3-7.0, SSP5-8.5). Daily mean WBGT demonstrated a stronger association with paediatric asthma EDVs than temperature alone. Exposure to high humid-heat (WBGT at the 95th percentile) was associated with a significant cumulative relative risk (RR) of 1.38 (95

PURPOSE:Gender nonconformity (GNC) describes the degree of misalignment between individual's gender expression and gender norms and is often linked to negative health outcomes. We aimed to investigate the association between GNC and adolescent indoor tanning, the most preventable cause of skin cancer, among U.S. high school students. METHODS:This study examined cross-sectional data from the 2017 state Youth Risk Behavior Survey in Maryland. Participants included 25,432 female and 25,060 male students in grades 9 through 12. The primary outcome was the prevalence of self-reported 12-month history of indoor tanning before survey. The GNC was measured by self-perceived gender expression (from "very feminine" to "very masculine") and sex ("female" or "male"). The logistic regression analysis for weighted survey data was performed to estimate the association between GNC and adolescent indoor tanning. RESULTS:Among 50,492 high school students in Maryland, the prevalence of indoor tanning was 6.8(95% CI, 6.4-7.3), and varied by demographic characteristics and sexual orientation. Among male students, indoor tanning was significantly associated with moderate GNC (AOR, 1.55; 95% CI, 1.13-2.13; P=0.007) and high GNC (AOR, 4.92; 95% CI, 4.04-5.99; P<0.001). However, among female students, indoor tanning was not associated with moderate and high GNC in the adjusted models. Furthermore, indoor tanning was also significantly associated with transgender identity, the AOR was 7.16 (95% CI, 5.89-8.72; P<0.001) compared with cisgender female students, and 9.31(7.44-11.64; P<0.001) compared with cisgender male students. CONCLUSIONS:Gender nonconforming adolescent males and transgender adolescents report higher risk of indoor tanning than gender conforming adolescent males and cisgender adolescents respectively. Skin cancer prevention efforts targeted at gender minorities might reduce indoor tanning, a preventable risk factor for skin cancer.

It remains unclear whether phthalates are associated with gallstones and whether the associations of phthalate alternatives with gallstones are different from traditional phthalates. In this study, 1735 participants from the NHANES 2017–2018 were included and their urine was used to detect phthalate metabolites. We used logistic and restricted cubic spline regressions to assess individual associations and dose–response relationships between phthalate metabolites and gallstones, quantile g-computation and Bayesian kernel machine regression to assess mixed associations of phthalate metabolites with gallstones, and subgroup analyses to explore potential effect modifiers. We observed that individual associations of cyclohexane-1,2-dicarboxylic acid-mono(carboxyoctyl) ester phthalate (MCOCHP) (OR: 1.423, 95

We used the Bayesian spatio-temporal model to describe the spatial and temporal distribution of the incidence and risk of mumps and evaluate the effects of meteorological factors, air pollutants and socioeconomic factors on the incidence of mumps in Gansu Province from 2015 to 2019 by using the incidence data of mumps in 87 districts and counties in Gansu Province from 2015 to 2019, as well as socio-economic data, meteorological data and some air pollutant data of each district and county in the same period. The incidence of mumps has increased in Gansu Province in recent years. The risk of mumps showed a decreasing and then increasing trend, and the areas with higher relative risk were mainly in Dingxi City, Jiuquan City and Jiayuguan City. The four variables of per capita gross domestic product, average temperature, nitrate and black carbon had positive effects on the incidence of mumps, and the relative risk of mumps increased by 14.5%, 21.5%, 101.7% and 21.6% for each unit increase in value, respectively. Targeted active interventions against anthropogenic sources of specific PM2.5 components and enhanced prevention and control under specific meteorological conditions can help prevent mumps.

OBJECTIVE:In the current study, we explored the associations between exposure to fine particulate matter (PM2.5) constituents and full-term small for gestational age (SGA) in different periods. METHODS:We included 155,897 participants, and matched the exposure concentrations of PM2.5 and its constituents [sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), organic matter (OM), and black carbon (BC)] according to participants' geographical location. To explore the associations of prenatal exposure to PM2.5 and its constituents with the risk of full-term SGA, we used logistic regression, restricted cubic spline regression (RCS) and quartile g-computation (QGCOMP). RESULTS:We found that individual exposure to PM2.5 and its constituents was positively associated with the risk of full-term SGA (P < 0.05), whether in the year before pregnancy or the entire pregnancy. These associations were more pronounced in the second trimester. We found that the risk of full-term SGA was positively and linearly related to the concentrations of PM2.5 and its constituents (Poverall < 0.05, Pnonlinear > 0.05). The associations of PM2.5 and its constituents with full-term SGA were stronger in multiparous mothers. Moreover, full-term SGA was associated with exposure to mixtures of SO42-, NO3-, NH4+, OM, and BC before pregnancy and in the second and third trimester. Among these, BC was positively associated with full-term SGA at each of the aforementioned stages. CONCLUSIONS:The risk of full-term SGA was positively and linearly related to concentrations of PM2.5 and its constituents, and these associations were more pronounced in the second trimester. BC was the most hazardous constituent of PM2.5 that was associated with full-term SGA.

To date, a limited number of studies have assessed the impact of individual and combined PM2.5 components on mumps incidence. Between 2013 and 2019, we collected data on 6270 mumps cases in Lanzhou, along with corresponding PM2.5 and its components, to analyze their temporal and spatial distributions. A generalized additive mixed model was constructed to examine the association between PM2.5 components and mumps incidence. Additionally, Bayesian kernel machine regression was used to evaluate the combined and interactive effects of co-exposure to PM2.5 components on mumps incidence and to identify key contributing components. A significant linear correlation was found between PM2.5 and mumps incidence at lag 1 month, with a relative risk (RR) of 1.85 (95 % CI: 1.14, 3.02) for each unit increase in PM2.5 (log-transformed PM2.5 concentration). Organic matter (OM) at lag 0 and 1 month, as well as black carbon (BC) at lag 1 month, were significantly positively correlated with mumps incidence. Furthermore, the joint exposure-effect curve for PM2.5 components and mumps incidence displayed an approximate V-shape. The effects of PM2.5 and its components on mumps incidence were more pronounced during the warm season. These findings suggest a significant association between short-term exposure to PM2.5 and its components and mumps incidence in Lanzhou, with potential variations in effect depending on the specific components of PM2.5.

Background Evidence has shown that the incidence of bacillary dysentery (BD) is associated with climatic factors. However, the lagged effects of climatic factors on BD are still unclear, especially lacking research evidence from arid and semi-arid regions. Therefore, this study aims to add new insights into this research field.Methods Spatial autocorrelation, time series analysis and spatiotemporal scans were used to perform descriptive analyses of BD cases from 2009 to 2019. On the basis of monthly data from 2015 to 2019, multivariable distributed lag non-linear models were used to investigate the lagged effects of climatic factors on BD.Results The hot spots for BD incidence are gradually decreasing and becoming increasingly concentrated in the southern part of Gansu Province. The maximum cumulative relative risks for monthly average temperature, sunshine duration, average relative humidity and precipitation were 3.21, 1.64, 1.55 and 1.41, respectively. The lagged effects peaked either in the current month or with a 1-month lag, and the shape of the exposure-response curve changed with the increase in maximum lag time. After stratification by per capita gross domestic product, there were differences in the effects.Conclusions Climatic factors can influence the incidence of BD, with effects varying across different lag times. It is imperative to vigilantly track the disparities in the incidence of BD attributable to economic factors.

Disturbances in the enterohepatic circulation are important biological mechanisms for causing gallstones and also have important effects on the metabolism of Per- and polyfluoroalkyl substances (PFAS). Moreover, PFAS is associated with sex hormone disorders, which are another important cause of gallstones. However, it remains unclear whether PFAS is associated with gallstones. In this study, we used logistic regression, restricted cubic spline (RCS), quantile g-computation (qg-comp), Bayesian kernel machine regression (BKMR), and subgroup analysis to assess the individual and joint associations of PFAS with gallstones and effect modifiers. We observed that the individual associations of perfluorodecanoic acid (PFDeA) (OR: 0.600, 95% CI: 0.444 to 0.811), perfluoroundecanoic acid (PFUA) (OR: 0.630, 95% CI: 0.453 to 0.877), n-perfluorooctane sulfonic acid (n-PFOS) (OR: 0.719, 95% CI: 0.571 to 0.906), and perfluoromethylheptane sulfonic acid isomers (Sm-PFOS) (OR: 0.768, 95% CI: 0.602 to 0.981) with gallstones were linearly negative. Qg-comp showed that the PFAS mixture (OR: 0.777, 95% CI: 0.514 to 1.175) was negatively associated with gallstones, but the difference was not statistically significant, and PFDeA had the highest negative association. Moreover, smoking modified the association of PFNA with gallstones. BKMR showed that PFDeA, perfluorononanoic acid (PFNA), and PFUA had the highest groupPIP (groupPIP=0.93); PFDeA (condPIP=0.82), n-perfluorooctanoic acid (n-PFOA) (condPIP=0.68), and n-PFOS (condPIP=0.56) also had high condPIPs. Compared with the median level, the joint association of the PFAS mixture with gallstones showed a negative trend. When the PFAS mixture level was at the 70th percentile or higher, they were negatively associated with gallstones. Meanwhile, when other PFAS were fixed at the 25th, 50th, and 75th percentiles, PFDeA had negative associations with gallstones. Our evidence emphasizes that PFAS is negatively associated with gallstones, and more studies are needed in the future to definite the associations of PFAS with gallstones and explore the underlying biological mechanisms.

Evidence on the association of fine particulate matter (PM2.5) exposure with stillbirth is limited and inconsistent, which is largely attributed to differences in PM2.5 constituents. Studies have found that the hazards of certain PM2.5 constituents to the fetus are comparable to or even higher than total PM2.5 mass. However, few studies have linked PM2.5 constituents to stillbirth. Moreover, the mediating role of pregnancy complications in PM2.5-related stillbirth remains unclear. To our knowledge, this study was the first to explore the individual and mixed associations of PM2.5 and its constituents with stillbirth in China. After matching the concentrations of PM2.5 and its constituents (sulfate [SO42−], nitrate [NO3−], ammonium [NH4+], organic matter [OM], and black carbon [BC]) for participants according to their geographical location, there were 170,507 participants included in this study. We found that stillbirth was associated with exposure to PM2.5 and its constituents in the year before pregnancy and during the entire pregnancy, and the associations in trimester 1 were strongest. The risk of stillbirth increased sharply when PM2.5 and its constituents during pregnancy exceeded the median concentrations. Moreover, stillbirth was associated with exposure to the mixtures of SO42−, NO3−, NH4+, OM, and BC before and during pregnancy (trimesters 1 and 2). Meanwhile, two-pollutant models also suggested stillbirth was associated with PM2.5 and its constituents in the year before and during pregnancy. The associations of PM2.5 and its constituents with stillbirth were stronger in mothers with advanced age and without cesarean delivery history. Additionally, hypertensive disorders in pregnancy, gestational diabetes, and placental abruption mediated the association of PM2.5 with stillbirth. Therefore, enhanced protection against PM2.5 for pregnant women before and during pregnancy and targeted interventions for pregnancy complications and anthropogenic sources of PM2.5 constituents are important to reduce stillbirth risk.

Objective To compare the outcomes of patients undergoing Retroperitoneal laparoscopic Radical nephrectomy (RLRN) and Transperitoneal laparoscopic Radical nephrectomy (TLRN). Methods A total of 120 patients with localized renal cell carcinoma were randomized into either RLRN or TLRN group. Mainly by comparing the patient perioperative related data, surgical specimen integrity, pathological results and tumor results. Results Each group comprised 60 patients. The two group were equivalent in terms of perioperative and pathological outcomes. The mean integrity score was significantly lower in the RLRN group than TLRN group. With a median follow-up of 36.4 months after the operation, Kaplan–Meier survival analysis showed no significant difference between RLRN and TLRN in overall survival (89.8% vs. 88.5%; P = 0.898), recurrence-free survival (77.9% vs. 87.7%; P = 0.180), and cancer-specific survival (91.4% vs. 98.3%; P = 0.153). In clinical T2 subgroup, the recurrence rate and recurrence-free survival in the RLRN group was significantly worse than that in the TLRN group (43.2% vs. 76.7%, P = 0.046). Univariate and multivariate COX regression analysis showed that RLRN (HR: 3.35; 95%CI: 1.12–10.03; P = 0.030), male (HR: 4.01; 95%CI: 1.07–14.99; P = 0.039) and tumor size (HR: 1.23; 95%CI: 1.01–1.51; P = 0.042) were independent risk factor for recurrence-free survival. Conclusions Our study showed that although RLRN versus TLRN had roughly similar efficacy, TLRN outperformed RLRN in terms of surgical specimen integrity. TLRN was also significantly better than RLRN in controlling tumor recurrence for clinical T2 and above cases. Trial registration Chinese Clinical Trial Registry ( https://www.chictr.org.cn/showproj.html?proj=24400 ), identifier: ChiCTR1800014431, date: 13/01/2018.

Scarlet fever (SF) is an acute respiratory transmitted disease that primarily affects children. The influence of meteorological factors and air pollutants on SF in children has been proved, but the relevant evidence in Northwest China is still lacking. Based on the weekly reported cases of SF in children in Lanzhou, northwest China, from 2014 to 2018, we used geographical detectors, distributed lag nonlinear models (DLNM), and bivariate response models to explore the influence of meteorological factors and air pollutants with SF. It was found that ozone (O3), carbon monoxide (CO), sulfur dioxide (SO2), temperature, pressure, water vapor pressure and wind speed were significantly correlated with SF based on geographical detectors. With the median as reference, the influence of high temperature, low pressure and high pressure on SF has a risk effect (relative risk (RR) > 1), and under extreme conditions, the dangerous effect was still significant. High O3 had the strongest effect at a 6-week delay, with an RR of 5.43 (95

The particulate matter with diameter of less than 2.5 µm (PM2.5) is an important risk factor for respiratory infectious diseases, such as scarlet fever, tuberculosis, and similar diseases. However, it is not clear which component of PM2.5 is more important for respiratory infectious diseases. Based on data from 31 provinces in mainland China obtained between 2013 and 2019, this study investigated the effects of different PM2.5 components, i.e., sulfate (SO42−), nitrate (NO3−), ammonium (NH4+), and organic matter (OM), and black carbon (BC), on respiratory infectious diseases incidence [pulmonary tuberculosis (PTB), scarlet fever (SF), influenza, hand, foot, and mouth disease (HFMD), and mumps]. Geographical probes and the Bayesian kernel machine regression (BKMR) model were used to investigate correlations, single-component effects, joint effects, and interactions between components, and subgroup analysis was used to assess regional and temporal heterogeneity. The results of geographical probes showed that the chemical components of PM2.5 were associated with the incidence of respiratory infectious diseases. BKMR results showed that the five components of PM2.5 were the main factors affecting the incidence of respiratory infectious diseases (PIP>0.5). The joint effect of influenza and mumps by co-exposure to the components showed a significant positive correlation, and the exposure-response curve for a single component was approximately linear. And single-component modelling revealed that OM and BC may be the most important factors influencing the high incidence of respiratory infections. Moreover, respiratory infectious diseases in southern and southwestern China may be less affected by the PM2.5 component. This study is the first to explore the relationship between different components of PM2.5 and the incidence of five common respiratory infectious diseases in 31 provinces of China, which provides a certain theoretical basis for future research.

BackgroundFrom January 2020 to December 2022, China implemented "First-level-response", "Normalized-control" and "Dynamic-COVID-zero" to block the COVID-19 epidemic; however, the immediate and long-term impact of three strategies on other infectious diseases and the difference in their impact is currently unknown. We aim to provide a more comprehensive understanding of the impact of non-pharmacological interventions (NPIs) on infectious diseases in China.MethodsWe collected data on the monthly case count of infectious diseases in China from January 2015 to July 2022. After considering long-term trends using the Cox-Stuart test, we performed the two ratio Z tests to preliminary analyze the impact of three strategies on infectious diseases. Next, we used a multistage interrupted-time-series analysis fitted by the Poisson regression to evaluate and compare the immediate and long-term impact of three strategies on infectious diseases in China.ResultsCompared to before COVID-19, the incidence of almost all infectious diseases decreased immediately at stages 1, 2, and 3; meanwhile, the slope in the incidence of many infectious diseases also decreased at the three stages. However, the slope in the incidence of all sexually transmitted diseases increased at stage 1, the slope in the incidence of all gastrointestinal infectious diseases increased at stage 2, and the slope in the incidence of some diseases such as pertussis, influenza, and brucellosis increased at stage 3. The immediate and long-term limiting effects of "Normalized-control" on respiratory-transmitted diseases were weaker than "First-level-response" and the long-term limiting effects of "Dynamic-COVID-zero" on pertussis, influenza, and hydatid disease were weaker than "Normalized-control".ConclusionsThree COVID-19 control strategies in China have immediate and long-term limiting effects on many infectious diseases, but there are differences in their limiting effects. Evidence from this study shows that pertussis, influenza, brucellosis, and hydatid disease began to recover at stage 3, and relaxation of NPIs may lead to the resurgence of respiratory-transmitted diseases and vector-borne diseases.

Mainland China included Japanese encephalitis (JE) vaccine in the national immunization program in 2008 to control the JE epidemic. However, Gansu province in Western China experienced the largest JE outbreak since 1958 in 2018. We conducted a retrospective epidemiological study to explore the causes of this outbreak. We found that adults aged ≥20 years (especially those in rural areas) were the main JE cases in Gansu Province, with a significant increase in the JE incidence in older adults aged ≥60 years in 2017 and 2018. In addition, JE outbreaks in Gansu Province were mainly located in the southeastern region, while the temperature and precipitation in Gansu Province were gradually increasing in recent years, which made the JE epidemic areas in Gansu Province gradually spread to the western of Gansu Province. We also found that adults aged ≥20 years in Gansu Province had lower JE antibody positivity than children and infants, and the antibody positivity rate decreased with age. In the summer of 2017 and 2018, the density of mosquitoes (mainly the Culex tritaeniorhynchus ) in Gansu Province was significantly higher than in other years, and the genotype of JEV was mainly Genotype‐G1. Therefore, in the future JE control in Gansu Province, we need to strengthen JE vaccination for adults. Moreover, strengthening mosquito surveillance can provide early warning of JE outbreaks and the spread of epidemic areas in Gansu Province. At the same time, strengthening JE antibody surveillance is also necessary for JE control.

BACKGROUND:The impact of COVID-19 on the epidemiology, clinical characteristics, and infection spectrum of viral and bacterial respiratory infections in Western China is unknown.METHODS:We conducted an interrupted time series analysis based on surveillance of acute respiratory infections (ARI) in Western China to supplement the available data.RESULTS:The positive rates of influenza virus, Streptococcus pneumoniae, and viral and bacterial coinfections decreased, but parainfluenza virus, respiratory syncytial virus, human adenovirus, human rhinovirus, human bocavirus, non-typeable Haemophilus influenzae, Mycoplasma pneumoniae, and Chlamydia pneumoniae infections increased after the onset of the COVID-19 epidemic. The positive rate for viral infection in outpatients and children aged <5 years increased, but the positive rates of bacterial infection and viral and bacterial coinfections decreased, and the proportion patients with clinical symptoms of ARI decreased after the onset of the COVID-19 epidemic. Non-pharmacological interventions reduced the positive rates of viral and bacterial infections in the short term but did not have a long-term limiting effect. Moreover, the proportion of ARI patients with severe clinical symptoms (dyspnea and pleural effusion) increased in the short term after COVID-19, but in the long-term, it decreased.CONCLUSIONS:The epidemiology, clinical characteristics, and infection spectrum of viral and bacterial infections in Western China have changed, and children will be a high-risk group for ARI after the COVID-19 epidemic. In addition, the reluctance of ARI patients with mild clinical symptoms to seek medical care after COVID-19 should be considered. In the post-COVID-19 era, we need to strengthen the surveillance of respiratory pathogens.

The "14th Five-Year Plan" period is the key stage for southern Hebei cities (Shijiazhuang, Xingtai, and Handan) to be removed from the bottom ten of the Air Quality Composite Index. The hourly ozone (O3) data of 15 country-controlled monitoring stations in the southern cities of Hebei Province from April to October 2020, hourly data of three volatile organic compound (VOCs) supersites, and the meteorological data of the same period were used for analysis, combined with the spatiotemporal succession, O3 formation potential (OFP), backward trajectory modeling, and spatial statistical modeling. The results showed the following:firstly, the temporal variations in O3 in southern cities of Hebei Province from April to October presented an inverted "U" shape, and the spatial distribution was high in the south and low in the north. O3 pollution was the most serious in June, with Xingtai (233.8 μg·m-3)>Handan (225.2 μg·m-3)>Shijiazhuang (224.8 μg·m-3). O3 was positively correlated with temperature and wind speed and negatively correlated with humidity and VOCs; furthermore, the ρ(TVOC) from April to October followed the order of Xingtai (274 μg·m-3)>Shijiazhuang (266 μg·m-3)>Handan (218 μg·m-3). The total OFP of alkenes and aromatics accounted for more than half; moreover, the trajectory of O3 pollution in southern cities of Hebei Province showed spatial directionality and relevance. The highest mass concentration of O3 (198.92 μg·m-3) was in the trajectory from Shijiazhuang to Xingtai, and the highest frequency of O3 pollution was in the trajectory from Handan to Xingtai. Moreover, the transmission contributions of O3from Xingtai to Shijiazhuang agglomerations were high (27.39%), and Handan played a significant role in the transmission contribution of O3 to Xingtai (32.76%).