Impact of biochar on the degradation rates of three pesticides by vegetables and its effects on soil bacterial communities under greenhouse conditions.

A 28 days pesticide degradation experiment was conducted for broccoli (Brassica oleracea L. var. italica Planch) and pakchoi (Brassica chinensis L.) with three pesticides (chlorantraniliprole (CAP), haloxyfop-etotyl (HPM), and indoxacarb (IXB)) to explore the effects of biochar on pesticide environmental fate and rhizosphere soil diversity. Rice straw biochar (RB) was applied to soil at a 25.00 t ha-1 dosage under greenhouse conditions, and its effects on the degradation of three pesticides in vegetables and in soil were investigated individually. Overall, RB application effectively facilitated CAP and HPM degradation in broccoli by 13.51-39.42% and in broccoli soil by 23.80-74.10%, respectively. RB application slowed the degradation of CAP, HPM and IXB in pakchoi by 0.00-57.17% and slowed the degradation of CAP in pakchoi by 37.32-43.40%. The results showed that the effect of RB application on pesticide degradation in crops and soil was related to biochar properties, pesticide solubility, plant growth status, and soil characteristics. Rhizosphere soil microorganisms were also investigated, and the results showed that biochar application may be valuable for altering bacterial richness and diversity. The effect of biochar application on pesticide residues in crops and soil was influenced by the vegetable variety first, and the second was pesticide characteristics. RB applied to soil at a 25.00 t ha-1 dosage under greenhouse conditions is recommended for broccoli production to ensure food safety. Our results suggested that biochar application in soil could reduce pesticide non-point source pollution, especially for highly soluble pesticides, and could affect soil microorganisms.

Efficacy of Voluntary Medical Male Circumcision to Prevent HIV Infection Among Men Who Have Sex With Men : A Randomized Controlled Trial.

BACKGROUND: Observational studies suggest that voluntary medical male circumcision (VMMC) may lower HIV risk among men who have sex with men (MSM). A randomized controlled trial (RCT) is needed to confirm this. OBJECTIVE: To assess the efficacy of VMMC in preventing incident HIV infection among MSM. DESIGN: An RCT with up to 12 months of follow-up. (Chinese Clinical Trial Registry: ChiCTR2000039436). SETTING: 8 cities in China. PARTICIPANTS: Uncircumcised, HIV-seronegative men aged 18 to 49 years who self-reported predominantly practicing insertive anal intercourse and had 2 or more male sex partners in the past 6 months. INTERVENTION: VMMC. MEASUREMENTS: Rapid testing for HIV was done at baseline and at 3, 6, 9, and 12 months. Behavioral questionnaires and other tests for sexually transmitted infections were done at baseline, 6 months, and 12 months. The primary outcome was HIV seroconversion using an intention-to-treat analysis. RESULTS: The study enrolled 124 men in the intervention group and 123 in the control group, who contributed 120.7 and 123.1 person-years of observation, respectively. There were 0 seroconversions in the intervention group (0 infections [95% CI, 0.0 to 3.1 infections] per 100 person-years) and 5 seroconversions in the control group (4.1 infections [CI, 1.3 to 9.5 infections] per 100 person-years). The HIV hazard ratio was 0.09 (CI, 0.00 to 0.81; P = 0.029), and the HIV incidence was lower in the intervention group (log-rank P = 0.025). The incidence rates of syphilis, herpes simplex virus type 2, and penile human papillomavirus were not statistically significantly different between the 2 groups. There was no evidence of HIV risk compensation. LIMITATION: Few HIV seroconversions and limited follow-up period. CONCLUSION: Among MSM who predominantly practice insertive anal intercourse, VMMC is efficacious in preventing incident HIV infection; MSM should be included in VMMC guidelines. PRIMARY FUNDING SOURCE: The National Science and Technology Major Project of China.

2 Year Wencheng Waxy Yam Pesticide Residue Investigation and Quality Evaluation.

Wencheng waxy yam is famous for its glutinous and resilient taste, similar to waxy rice, but there is currently a lack of systematic research on the quality of this featured product, and little is known about its pesticide residues. We carried out a 2 year investigation of Wencheng waxy yam at seven sites from 2021 to 2022 to determine the oxidase content and phytochemical characteristics, namely, amylose, amylopectin, protein, reducing sugar, and mineral contents, such as K, Fe, and Zn, including the status of pesticide residues. The results showed that the oxidase content was affected by rainfall, and adequate water reduced the production of oxidase, including polyphenol oxidase, peroxidase, and superoxide dismutase, during the late growth stage of waxy yam, which was beneficial for reducing browning in yam processing. Radar map analysis showed that, with comprehensive evaluation, standardized production sites 1 and 2 had a relatively higher quality than 3-7 with small farmers. The results of pesticide multiresidue testing showed that no pesticides were detected in 64.29% of the samples, and the detected residues in the samples were very low, making the consumption of yam safe for consumers. These findings could be beneficial for the exploitation of the health benefits of waxy yam tubers and the innovation of yam-based functional products.

Voluntary Medical Male Circumcision and Incident HIV Infection Among Men Who Have Sex With Men in China (The CoM Study): Protocol for a Randomized Controlled Trial.

BACKGROUND: Systematic reviews and meta-analyses based on observational studies have shown voluntary medical male circumcision (VMMC) may reduce HIV risk among men who have sex with men (MSM). There is a lack of randomized controlled trial (RCT) data assessing the efficacy of VMMC. OBJECTIVE: The primary objective of this study was to assess the efficacy of VMMC for preventing HIV acquisition among MSM who primarily engage in insertive anal sex. METHODS: A multicenter RCT will be conducted among MSM in 8 cities in China. Eligible participants are men aged 18-49 years who self-report ≥2 male sex partners in the past 6 months, predominantly practice insertive anal sex, and are willing to undergo circumcision. Interested men who satisfy inclusion criteria will be tested for HIV 1 month before enrollment and at enrollment, and only those who are HIV negative will be enrolled. At baseline, all enrolled participants will be asked to report sociodemographic characteristics and sexual behaviors; provide a blood sample for HIV, syphilis, and herpes simplex virus type 2 testing; and provide a penile swab for human papillomavirus testing. Participants will be randomly assigned to the intervention or control group. Those in the intervention group will receive VMMC and undergo a web-based weekly follow-up assessment of postsurgery healing for 6 consecutive weeks. All participants will be tested for HIV at 3-, 6-, 9-, and 12-month follow-ups. All participants will also be asked to report sexual behaviors and undergo repeat herpes simplex virus type 2 and human papillomavirus testing at 6- and 12-month follow-ups. The primary end point is HIV seroconversion. Secondary end points are the safety and satisfaction with VMMC and the changes in sexual behaviors after VMMC. The grouped censored data will be analyzed by intention-to-treat approach. RESULTS: Recruitment for the RCT began in August 2020 and continued through July 2022. Data collection is expected to be completed by July 2023, and full data analysis is going to be completed by September 2023. CONCLUSIONS: This study will be the first RCT to assess the efficacy of VMMC in preventing HIV infection among MSM. Results from this trial will provide preliminary evidence for the potential efficacy of VMMC to reduce incident HIV infection among MSM. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2000039436; https://www.chictr.org.cn/showproj.html?proj=63369. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/47160.

Management of cesarean scar pregnancy: Importance of gestational age at diagnosis and disease type-A single center's 5 years of experience involving 223 cases.

Objective: This study aims to evaluate the importance of the gestational age at diagnosis and the types of cesarean scar pregnancy (CSP) for treatment outcomes and to identify the optimal treatment based on both the gestational age at diagnosis and the CSP type. Methods: A retrospective cohort study included 223 pregnant women diagnosed with CSP at Peking University First Hospital, Beijing, China, between 2014 and 2018. All CSP cases underwent ultrasound-guided vacuum aspiration followed by supplementary curettage. Adjuvant treatment modalities included intramuscular injection of systemic methotrexate, uterine artery embolization, and hysteroscopy before ultrasound-guided vacuum aspiration. Linear regression was used to determine the relationship between intraoperative blood loss and gestational age at diagnosis, CSP type, highest ß-human chorionic gonadotropin level, and management procedures. Results: None of the patients required blood transfusions or hysterectomies. Patients presenting at <8, 8-10, and >10 weeks had median estimated blood loss of 5, 10, and 35 ml, respectively. Patients with type I CSP, type II CSP, and type III CSP had median blood loss of 5, 5 and 10 ml, respectively. Multivariate linear regression analysis demonstrated that the gestational age at diagnosis (p < 0.001) and type of CSP (p = 0.023) were independent predictors of intraoperative estimated blood loss. For type I CSP patients, ultrasound-guided vacuum aspiration followed by supplementary curettage alone was performed in 15 of 34 (44.1%) patients, including 12/27 (44.4%) diagnosed at <8 weeks, 2/6 (33.3%) at 8-10 weeks, and 1/1 for >10 weeks. In type II CSP patients, fewer cases were managed by ultrasound-guided vacuum aspiration followed by supplementary curettage alone as the gestational age at diagnosis increased [18/96 (18.8%) for <8 weeks, 7/41 (17.1%) for 8-10 weeks, none for >10 weeks]. Most type III CSP patients (41/45, 91.1%) needed treatments in addition to the ultrasound-guided vacuum aspiration regardless of the gestational age at diagnosis. All CSP patients were treated successfully and did not require readmission or further medical interventions. Conclusion: Gestational age at diagnosis of CSP and its type show a strong correlation with estimated blood loss during ultrasound-guided vacuum aspiration. With careful management, CSPs may be treated at any gestational week, regardless of their type, with minimal intraoperative bleeding.

Risk Compensation in Voluntary Medical Male Circumcision Programs.

PURPOSE OF REVIEW: Evidence from clinical trials identified the effectiveness of voluntary medical male circumcision (VMMC) as an additional strategy to reduce the risk of HIV transmission from women to men. However, concerns about post-circumcision sexual risk compensation may hinder the scale-up of VMMC programs. We reviewed the evidence of changes in risky sexual behaviors after circumcision, including condomless sex, multiple sex partners, and early resumption of sex after surgery. RECENT FINDINGS: Most clinical trial data indicate that condomless sex and multiple partners did not increase for men after circumcision, and early resumption of sex is rare. Only one post-trial surveillance reports that some circumcised men had more sex partners after surgery, but this did not offset the effect of VMMC. Conversely, qualitative studies report that a small number of circumcised men had increased risky sexual behaviors, and community-based research reports that more men resumed sex early after surgery. With the large-scale promotion and expansion of VMMC services, it may be challenging to maintain effective sexual health educations due to various restrictions. Misunderstandings of the effect of VMMC in preventing HIV infection are the main reason for increasing risky sexual behaviors after surgery. Systematic and practical sexual health counseling services should be in place on an ongoing basis to maximize the effect of VMMC.

COVID-19 vaccination perception and uptake among cancer patients in Guangzhou, China.

Patients with cancer are considered at high risk of COVID-19 related complications with higher mortality rates than healthy individuals. This study investigated the perception, acceptance, and influencing factors of COVID-19 vaccination among cancer patients in Guangzhou, China. A cross-sectional survey was conducted in Guangzhou, China from August to November 2021 in two tertiary medical centers. Outpatients were recruited through hospital posters to complete a questionnaire including demographics, medical history, knowledge, and attitude toward COVID-19 vaccines and COVID-19 vaccination status. Chi-square tests and multivariable logistic regression were used to analyze predictors for acceptance of COVID-19 vaccination. In total, only 75 out of 343 patients (21.87%) had received at least one dose of COVID-19 vaccine. Twenty-one patients (6.12%) had received a recommendation about COVID-19 vaccination from their physicians. Patients who were recommended by physicians to get vaccinated (aOR = 11.71 95% CI: 2.71-50.66), with a monthly income of more than CNY 5000 (aOR = 3.94, 95% CI: 1.88-8.26) were more likely to have received COVID-19 vaccination. Cancer patients who had been diagnosed for more than one year (aOR = 0.21, 95% CI: 0.09-0.51), had received multiple cancer treatment strategies (aOR = 0.34, 95% CI: 0.16-0.74), worried about the safety of COVID-19 vaccines (aOR = 0.21, 95% CI: 0.11-0.40), were less likely to have received COVID-19 vaccination. COVID-19 vaccination uptake among cancer patients was insufficient. The proportion of cancer patients receiving vaccination recommendations from physicians remains inadequate. Physicians are expected to play an essential role in patients' knowledge of the safety and effectiveness of COVID-19 vaccines.

Global Pattern and Trends in Penile Cancer Incidence: Population-Based Study.

BACKGROUND: Penile cancer is a relatively rare genital malignancy whose incidence and mortality are rising in many countries. OBJECTIVE: This study aims to assess the recent incidence and mortality patterns and incidence trends of penile cancer. METHODS: The age-standardized incidence and mortality rates (ASIR and ASMR, respectively) of penile cancer in 2020 were estimated from the Global Cancer Registries (GLOBOCAN) database. Incidence trends of penile cancer from 1973 to 2012 were assessed in 44 populations from 43 countries using the Cancer Incidence in Five Continents plus (CI5plus) and the Nordic Cancer Registries (NORDCAN) databases. Average annual percentage change was calculated to quantify trends in ASIR using joinpoint regression. RESULTS: Globally, the estimated ASIR and ASMR of penile cancer were 0.80 (per 100,000) and 0.29 (per 100,000) in 2020, equating to 36,068 new cases and 13,211 deaths in 2020, respectively. There was no significant correlation between the ASIR (P=.05) or ASMR (P=.90) and Human Development Index. In addition, 15 countries saw increasing ASIR for penile cancer, 13 of which were from Europe (United Kingdom, Lithuania, Norway, Estonia, Finland, Sweden, Cyprus, Netherlands, Italy, Croatia, Slovakia, Russia, and the Czech), and 2 from Asia (China and Israel). CONCLUSIONS: Although the developing countries still bear the higher incidence and mortality of penile cancer, the incidence is on the rise in most European countries. To mitigate the disease burden resulting from penile cancer, measures to lower the risk for penile cancers, including improving penile hygiene and male human papillomavirus vaccination, may be warranted.

Maternal outcomes of abnormally invasive placenta in China and their association with use of abdominal aortic balloon occlusion.

OBJECTIVE: To compare maternal outcomes of abnormally invasive placenta in China in 2012, 2015, and 2018, and further examine the association between use of abdominal aortic balloon occlusion (AABO) and the risk of maternal outcomes. MATERIALS AND METHODS: A retrospective analysis included 830 women diagnosed as abnormally invasive placenta from 5 tertiary care centers in China in 2012, 2015 and 2018. Participants were divided into AABO group and non-AABO group according to whether they were treated with AABO or not. Logistic regression models were used to assess the association of use of AABO with postpartum hemorrhage, blood transfusion, hysterectomy and repeated surgery. RESULTS: Among 830 participants, 66.0% (548/830) and 34.0% (282/830) of women were diagnosed with placenta increta and percreta, respectively; 33.3% (276/830) of women with abnormally invasive placenta were treated with AABO. In 2012, 2015, and 2018, the rate of blood transfusion was 83.1, 59.8, and 56.2%; the rate of hysterectomy was 50.8, 11.2, and 2.4%; and the rate of repeated surgery was 10.2, 9.4, and 0.9%. Use of AABO was associated with lower risk of postpartum hemorrhage (OR = 0.59, 95% CI: 0.35-0.99), blood transfusion (OR = 0.72, 95% CI: 0.52-0.99), hysterectomy (OR = 0.04, 95% CI: 0.01-0.14) and repeated surgery (OR = 0.14, 95% CI: 0.05-0.41) after adjustment for potential confounders. CONCLUSION: The rates of blood transfusion, hysterectomy and repeated surgery progressively decreased from 2012 to 2018 in Chinese women with abnormally invasive placenta. Use of AABO was associated with lower risk of postpartum hemorrhage, blood transfusion, hysterectomy and repeated surgery.

Intra-abdominal aortic balloon occlusion in the management of placenta percreta.

BACKGROUND: Massive bleeding is the main concern for the management of placenta percreta (PP). Intra-abdominal aortic balloon occlusion (IABO) is one method for pelvic devascularization, but the efficacy of IABO is uncertain. This study aims to investigate the outcomes of IABO in PP patients. METHODS: We retrospectively reviewed the clinical data of PP cases from six tertiary centers in China between January 2011 and December 2015. PP cases with/without the use of IABO were analyzed. Propensity score matching analysis was performed to reduce the effect of selection bias. Postpartum hemorrhage (PPH) and the rate of hysterectomy, as well as neonatal outcomes, were analyzed. RESULTS: One hundred and thirty-two matched pairs of patients were included in the final analysis. Compared with the control group, maternal outcomes, including PPH (68.9% vs. 87.9%, χ2 = 13.984, P < 0.001), hysterectomy (8.3% vs. 65.2%, χ2 = 91.672, P < 0.001), and repeated surgery (1.5% vs. 12.1%, χ2 = 11.686, P = 0.001) were significantly reduced in the IABO group. For neonatal outcomes, Apgar scores at 1 minute (8.67 ±â€Š1.79 vs. 8.53 ±â€Š1.68, t = -0.638, P = 0.947) and 5 minutes (9.43 ±â€Š1.55 vs. 9.53 ±â€Š1.26, t = 0.566, P = 0.293) were not significantly different between the two groups. CONCLUSIONS: IABO can significantly reduce blood loss, hysterectomies, and repeated surgeries. This procedure has not shown harmful effects on neonatal outcomes.

Association Between Pre-delivery Coagulation Indicators and Invasive Placenta Accreta Spectrum.

OBJECTIVES: To analyze the association between pre-operational coagulation indicators and the severity of placenta accreta spectrum (PAS), as well as blood loss volume during operation. METHODS: Hospitalized patients of the obstetric department in a major hospital from 2018 to 2020 who were clinically and/or pathologically diagnosed with invasive PAS were included. Univariate and multivariate logistic regression and Poisson regression models were used to quantify the association between each of the 6 coagulation indicators and PAS severity (measured by FIGO grade) as well as maternal outcomes. RESULTS: Ninety-five patients (46 FIGO grade 2 and 49 FIGO grade 3) were included. Higher PT [adjusted OR (aOR): 5.54; 95% CI, 1.80 to 17.07] and FDP (aOR: 1.19; 95% CI, 1.01-1.42) levels were associated with an increased risk of FIGO grade 3 after adjusting for covariates. D-dimer [incidence rate ratio (IRR): 1.19; 95% CI, 1.05 to 1.35)] and FDP (IRR: 1.03; 95% CI, 1.01-1.04) levels were significantly associated with higher blood loss volume after adjusting for covariates. CONCLUSION: Preoperative coagulation indicators, especially PT, D-dimer and FDP, are associated with disease severity and blood loss volume during operation of invasive PAS. The underlying mechanism for the coagulation profile of PAS patients warrants further analysis. SYNOPSIS: Preoperative coagulation indicators, especially PT, D-dimer and FDP, are associated with disease severity and blood loss volume during operation among invasive placenta accreta spectrum patients.

Genome-Wide Identification and Characterization of Long Noncoding RNAs Involved in Chinese Wheat Mosaic Virus Infection of Nicotiana benthamiana.

Recent studies have shown that a large number of long noncoding RNAs (lncRNAs) can regulate various biological processes in animals and plants. Although lncRNAs have been identified in many plants, they have not been reported in the model plant Nicotiana benthamiana. Particularly, the role of lncRNAs in plant virus infection remains unknown. In this study, we identified lncRNAs in N. benthamiana response to Chinese wheat mosaic virus (CWMV) infection by RNA sequencing. A total of 1175 lncRNAs, including 65 differentially expressed lncRNAs, were identified during CWMV infection. We then analyzed the functions of some of these differentially expressed lncRNAs. Interestingly, one differentially expressed lncRNA, XLOC_006393, was found to participate in CWMV infection as a precursor to microRNAs in N. benthamiana. These results suggest that lncRNAs play an important role in the regulatory network of N. benthamiana in response to CWMV infection.

Guizhi Fuling Capsule Exhibits Antidysmenorrhea Activity by Inhibition of Cyclooxygenase Activity.

Guizhi Fuling capsule (GZFLc) is a modern preparation from traditional Chinese Medicine. Guizhi Fuling was first prescribed by Zhang Zhongjing almost two thousand years ago for the treatment of primary dysmenorrhea. It has also been used to treat uterine fibroids, dysfunctional uterine bleeding, and endometriosis. Although effective against dysmenorrhea clinically, there are limited information on the mechanism of its action. The major components responsible for the activity are not well defined. The aim of this study has been to elucidate a mechanism that may facilitate the development of a bioactivity-based assay for quality control during drug formulation and manufacturing. Using an oxytocin-induced mouse dysmenorrhea model, we showed that oral administration of GZFLc at 150 and 300 mg/kg, dosages relevant to clinic usages, significantly suppressed oxytocin-induced writhing response. The antidysmenorrhea effect was also demonstrated by a rotarod assay. We showed that GZFLc treatment significantly prolonged the hanging time of mice on the rotating rod. Histological studies showed that GZFLc treatment reduced lamina propria edema, while no effect on COX2 expression was detected. GZFLc instead exhibited direct inhibitory effect against COX2, a critical enzyme that catalyzes arachidonic acid conversion to prostaglandins. By HPLC profiling, we showed that paeoniflorin, paeonol, and cinnamaldehyde are the major components from the corresponding plants. At 5 and 10 mg/kg, both paeoniflorin and paeonol were active against induced dysmenorrhea. The study not only links GZFLc antidysmenorrhea activity to COX2 inhibition but also uncovers a mechanism of action by which an assay can be developed for bioefficacy evaluation of GZFLc.

NbWRKY40 Positively Regulates the Response of Nicotiana benthamiana to Tomato Mosaic Virus via Salicylic Acid Signaling.

WRKY transcription factors play important roles in plants, including responses to stress; however, our understanding of the function of WRKY genes in plant responses to viral infection remains limited. In this study, we investigate the role of NbWRKY40 in Nicotiana benthamiana resistance to tomato mosaic virus (ToMV). NbWRKY40 is significantly downregulated by ToMV infection, and subcellular localization analysis indicates that NbWRKY40 is targeted to the nucleus. In addition, NbWRKY40 activates W-box-dependent transcription in plants and shows transcriptional activation in yeast cells. Overexpressing NbWRKY40 (OEWRKY40) inhibits ToMV infection, whereas NbWRKY40 silencing confers susceptibility. The level of salicylic acid (SA) is significantly higher in OEWRKY40 plants compared with that of wild-type plants. In addition, transcript levels of the SA-biosynthesis gene (ICS1) and SA-signaling genes (PR1b and PR2) are dramatically higher in OEWRKY40 plants than in the control but lower in NbWRKY40-silenced plants than in the control. Furthermore, electrophoretic mobility shift assays show that NbWRKY40 can bind the W-box element of ICS1. Callose staining reveals that the plasmodesmata is decreased in OEWRKY40 plants but increased in NbWRKY40-silenced plants. Exogenous application of SA also reduces viral accumulation in NbWRKY40-silenced plants infected with ToMV. RT-qPCR indicates that NbWRKY40 does not affect the replication of ToMV in protoplasts. Collectively, our findings suggest that NbWRKY40 likely regulates anti-ToMV resistance by regulating the expression of SA, resulting in the deposition of callose at the neck of plasmodesmata, which inhibits viral movement.

Health risk assessment of Chinese consumers to Cadmium via dietary intake.

This paper investigated the concentration of Cd in foods via surveys and a literature review. The concentration of Cd in different food groups was in the decreasing order of meat > aquatic products > cereal > vegetable > bean > egg > dairy > fruit. More precisely, on average the weekly Cd intake for men, women, 2-3-year-old children and 4-17-year-old children were 0.0039, 0.0041, 0.0069 and 0.0064mgkg-1 bw week-1, respectively. Among all food groups, cereal was the most significant contributor to the dietary intake of Cd, followed by vegetable, aquatic products and meat. For Chinese consumers, the results of risk assessment for all groups by the deterministic method and the probabilistic method showed the mean weekly Cd intake via dietary exposure was lower than the provisional tolerable weekly intake (PTWI) proposed by WHO. However, the 95th and 97.5th percentile THQ values all exceeded 1, and the probability of dietary Cd exposure greater than the weekly intake tolerance (THQ >1) were 15.9%, 17.1%, 42.3% and 28.4% for men, women, 2-3-year-old children and 4-17-year-old children, indicating a potential risk from Cd exposure via dietary intake, especially for children. It appeared that dietary Cd exposure should deserve our attention, and positive measures must be taken to reduce the concentration of Cd in food at once.

Polycyclic aromatic hydrocarbons in urban soils of Hangzhou: status, distribution, sources, and potential risk.

Concentration, composition profile, spatial distribution, sources, and health risk of 16 polycyclic aromatic hydrocarbons (PAHs) were analyzed in 69 surface soil samples collected from Hangzhou urban districts. ∑PAHs ranged from 180.77 to 1,981.45 µg kg(-1) with a mean of 611.28 µg kg(-1). Among different functional areas, a higher level of PAHs was found in the roadsides, followed by commercial districts, residential areas, parks, and greenbelts. The composition of PAHs was characterized by high molecular weight PAHs (4 ~ 6 rings). Principal component analysis (PCA) and PAH isomeric ratios indicated that PAHs mainly originated from combustion, especially vehicle exhaust. The incremental lifetime cancer risks (ILCRs) associated with exposures to PAHs in soil were calculated separately for children and adults under normal and extreme conditions. The results showed that ILCRs for urban soil of Hangzhou were acceptable. However, attentions should be attracted on the sites of high PAH concentrations because the ILCRs were closed to 10(-4) under extreme conditions, especially for children.