Determinants of Willingness to Use PrEP Among Gay and Bisexual Men in China Before Implementation: A Structural Equation Modeling Assessment.

With the recent endorsement of PrEP by the Chinese government, research is urgently needed to better understand factors impacting PrEP uptake among gay, bisexual, and other men who have sex with men (GBMSM) in China. This study examined willingness to use PrEP for HIV prevention among GBMSM in China through structural equation modeling. We examined the relationship among PrEP-related attitudes, subjective norms, PrEP-related knowledge and beliefs about medicines and willingness to use PrEP. The analysis showed a good fit between the data and both the measurement model (RMSEA = 0.060) and structural model (RMSEA = 0.054). Knowledge, attitudes, and subjective norms were significantly related to intention to use PrEP, whereas the effect of general beliefs about medicines was insignificant. These effect mechanisms point to the importance of designing interventions to support PrEP uptake that target knowledge, enhance positive attitudes about PrEP within social networks, and build positive social norms around PrEP among sexually active GBMSM.

[Profile Characteristics of VOCs from Wood and Economic Crop Burning].

Wood and economic crops are still widely used in rural areas of China. Although their combustion is an important source of volatile organic compounds (VOCs), study on their emission characteristics is relatively weak. In this study, three kinds of wood (poplar, cedarwood, and citrus branches) and six economic crop straws (soybean stalk, sesame stalk, corn cob, cotton stalk, peanut stalk, and corn stalk) were selected and their burning was simulated in the laboratory. A dilution tunnel system was used to dilute the smoke, and then Tedlar bags were used to collect the smoke. The compositions of 102 VOCs were analyzed by Agilent 7820A/5977E gas chromatography/mass spectrometry. The ozone formation potential (OFP) of VOCs for different types of biomass burning was analyzed. The results indicated that there are differences in the VOC compositions of different types of biomass burning emissions. Ethane (11.1%), trans-2-pentene (15.4%), ethylene (8.3%), and dichloromethane (11.9%) are the main VOCs emitted from poplar and cedarwood burning. Toluene (49.8%) is the most abundant species of VOC emitted from burning of citrus branches. Ethylene (11.8%-17.5%) and acetone (9.2%-14.7%) are the main VOCs components of straw burning. Corn stalks, peanut stalks, and citrus branches have similar VOC source profiles, with the coefficient of divergence less than 0.1. The benzene/toluene ratio for biomass burning emissions obtained in this study and in the literature is in the range of 0.030-6.48. It is arguable that a value higher than 1 indicated the impact of biomass burning. The contributions of alkenens, oxygenated VOCs, and aromatic hydrocarbons to the OFP of biomass burning were 30.6%-80.3%, 6.5%-21.0%, and 3.8%-56.5%, respectively. The components contributing more than 10.0% to the OFP are ethylene, propylene, trans-2-pentene, cis-2-pentene, toluene, and propionaldehyde.

Do gay and bisexual men who conceal their same-sex behavior prefer different kinds of health services? Findings across four cities to inform client-centered HIV prevention in China.

BACKGROUND: In China, addressing disparities in the HIV epidemic among men who have sex with men (MSM) requires targeted efforts to increase their engagement and retention in prevention. In an effort to advance MSM-friendly HIV services within China, and informed by community-based partnerships, we tested whether MSM who have ever versus never disclosed their same-sex behavior to healthcare providers (HCP) differ in sociodemographic and behavioral characteristics as well as the qualities of sexual health services each group would prefer to access. METHODS: We conducted a cross-sectional survey among HIV-negative MSM who went to MSM-focused voluntary counseling and testing clinics in four cities in China. The survey was anonymous and collected information on sociodemographic characteristics, testing behaviors, sexual-health related behavior, and sexual health service model preferences. RESULTS: Of 357 respondents, 68.1% participants had ever disclosed same-sex behavior to HCPs when seeking advice for sexual health. Younger age (aOR = 1.04; 95% CI: 1.01-1.08), and worry of HIV acquisition (aOR = 1.39; 95% CI: 1.05-1.84) were associated with higher odds of past disclosure. The availability of comprehensive sexual health services was one of the most valued characteristics of the ideal sexual health clinic. Those who ever disclosed and never disclosed differed significantly in their ranking of the importance of three out of ten dimensions: sexual health counseling services available (M = 3.99 vs. M = 3.65, p = .002), gay identity support available (M = 3.91 vs. M = 3.62, p = .016) and clinic collaborates with a gay CBO (M = 3.81 vs. M = 3.56, p = .036). CONCLUSIONS: Our hypothesis that MSM who had disclosed versus never disclosed same-sex behavior would differ in the value they placed on different dimensions of sexual health service was partially borne out. As health authorities in China decide on implementation models for pre-exposure prophylaxis (PrEP) delivery and specifically within which institutions to integrate PrEP services, the preferences of target populations should be considered to develop comprehensive, patient-centric and LGBT-friendly services.

Investigation of polycyclic aromatic hydrocarbons in soils from Caserta provincial territory, southern Italy: Spatial distribution, source apportionment, and risk assessment.

The concentrations of polycyclic aromatic hydrocarbons (PAHs) in soils from Caserta provincial territory, southern Italy, were systematically investigated along with their correlations with soil properties and health risk. The concentrations of ∑16PAHs ranged from 10.0 to 4191 ng/g, with a median (1 st quartile, Q1; 3rd quartile, Q3) of 28.5 (17.5-65.0) ng/g; Four-ring PAHs were the most abundant and contributed an average of ∼50.2% of the ∑16PAHs. Significant differences in the spatial distributions of PAHs in soil were observed, with higher levels of PAH contamination found in Caserta city and the surrounding areas. According to the positive matrix factorization (PMF) model, three sources were identified: chemical production and metal smelting, vehicle emissions, and coal/biomass combustion. Soil total organic carbon was significantly correlated with the concentration of total PAHs and the concentrations of PAHs with three-, four-, and five-rings. In contrast, only the concentration of ∑4DBPs (dibenzo(a,e)pyrene, dibenzo(a,h)pyrene, dibenzo(a,i)pyrene, dibenzo(a,l)pyrene) was well correlated with population density. The soil mass inventory of ∑16PAHs was estimated to be 6.87 metric tons (geometric mean). The ecological risks posed by PAHs in the study are negligible; however, health risks of exposure to soil-borne PAHs were identified based on a probabilistic risk model.

Polycyclic aromatic hydrocarbons (PAHs) in agricultural soils from Ningde, China: levels, sources, and human health risk assessment.

Soil-bound polycyclic aromatic hydrocarbons (PAHs) in farmland are critical to human health. The level, composition, source, and cancer risk of sixteen PAHs in agricultural soil from Ningde, China, were investigated. The results indicated that the total concentrations of 16 PAHs ranged from 77.3 to 1188 ng g-1, with a mean value of 406 ng g-1. Five-ring PAHs were found to have the highest concentrations (148 ± 133 ng g-1), followed by four-ring (120 ± 101 ng g-1), three-ring (61.9 ± 54.2 ng g-1), six-ring (44.6 ± 61.0 ng g-1), and two-ring (31.3 ± 31.0 ng g-1). Employing positive matrix factorization (PMF), four PAH sources including biomass burning (36.3%), coal combustion (35.5%), traffic emissions (16.4%), and coke source (11.8%) were identified. Incremental lifetime cancer risk (ILCR) results showed that ILCR values ranged from 7.1 × 10-4 to 1.1 × 10-3, which will cause moderate-to-high cancer risk to human health mainly via the soil ingestion and dermal contact exposure pathways. The source-oriented results indicated that coal combustion (32.7%), traffic emission (34.3%), and biomass burning (32.4%) had similar contributions to the total cancer risk. Therefore, more attention should be paid to these pyrolysis-originated sources to protect humanity from the health risk of PAHs.

Mitigating circumstances: A model-based analysis of associations between risk environment and infrequent condom use among Chinese street-based sex workers.

BACKGROUND: Little is known about how freelance street-based sex workers navigate condom use while soliciting. Traditional behavioural model may fail to account for the complex risk environment that most street-based sex workers work within. We examine first the association of self-efficacy and the infrequent condom use, then we investigated the roles of clients and venues frequented on this association. METHOD: Using a purposive chain-referral sampling method, we surveyed 248 street-based sex workers in Shanghai. The survey focused on sex workers HIV risk factors, sex work patterns, HIV knowledge, and related HIV self-efficacy. Clients types and behaviours, and characteristics of the venues frequented by these commercial sex workers were also collected. We conducted a series of multiple logistic regression models to explore how the association between a sex worker's self-efficacy with infrequent condom use change as client and venue characteristics were added to the models. RESULTS: We find that within the basic model, low self-efficacy was marginally associated with infrequent condom use (54.9% vs. 45.1%, AOR = 1.70, 95% CI = 0.95-3.03). As client- and venue- characteristics were added, the associations between self-efficacy and condom use were strengthened (AOR = 2.10 95% CI = 1.12-3.91 and 2.54 95% CI = 1.24-5.19 respectively). Those who reported middle-tiered income were more likely to report infrequent condom use compared to their peers of high income (AOR = 3.92 95% CI = 1.32-11.70) whereas such difference was not found between low income and high income sex workers. Visiting multiple venues and having migrant workers as clients were also associated with infrequent condom use. CONCLUSION: Our findings suggest sex worker's self-efficacy matters in their HIV risk behaviours only when environment characteristics were adjusted. Risk environment for street-based sex workers are complex. Programming addressing behavioural changes among female sex workers should adopt holistic, multilevel models with the consideration of risk environments.

Biomass burning contributed most to the human cancer risk exposed to the soil-bound PAHs from Chengdu Economic Region, western China.

The purpose of this study was to assess the human cancer risk due to the exposure to the soil-bound polycyclic aromatic hydrocarbons (PAHs) from Chengdu Economic Region (CER), western China with the main concern on cancer risk source apportionment. The total concentrations of sixteen PAHs ranged from 12.5 to 75431 ng g-1, with a mean value of 3106 ng g-1, which suggested that the most areas of CER were contaminated. Source apportionment of PAHs was conducted by the positive matrix factorization (PMF) model and the biomass burning contributed most (63.6%) to the total PAHs, followed by petroleum combustion (16.0%), coke source (11.3%), and petrogenic source (9.2%). Results from incremental lifetime cancer risk (ILCR) calculation showed that soil ingestion exerted the highest cancer risk (accounted for 98.1 - 99.3% of the total cancer risk) on human health among three different exposure pathways, followed by dermal contact (0.66 - 1.83%) and inhalation (0.03 - 0.04%). Among different age groups, adult suffered the highest cancer risk via any exposure pathways. Based on PMF and ILCR methods, the cancer risk source apportionment was conducted and the biomass burning showed moderate cancer risk. The petrogenic, coke, and petroleum sources showed low cancer risks to human. To analyze the sensitivity of the parameters used in ILCR calculation, Monte Carlo simulation was employed. The results indicated that the contribution of each source and exposure duration (ED) were the influential parameters on human health associated with soil-bound PAHs. Therefore, much attentions should be paid to biomass burning to avoid cumulative cancer risk.

[Distribution, Sources and Risk Assessment of the PAHs in the Surface Sediments and Water from the Daye Lake].

8 surface sediments and 8 water samples were collected from the Daye Lake in August 2015.The 16 kinds of EPA control polycyclic aromatic hydrocarbons (PAHs) were analyzed by GC-MS.The results showed that the PAHs concentrations of surface sediments and water ranged from 35.94 ng·g-1 to 2032.73 ng·g-1 and from 27.94 ng·L-1 to 242.95 ng·L-1,with average contents of 940.61 ng·g-1 and 107.77ng·L-1,respectively.The distribution of PAHs in surface sediments indicated that the contents in the center samples were higher than those in the bank samples,but the water showed nearly the opposite tendency.The 4-5 rings high molecular weight PAHs were the main components in the surface sediments,and the 2,4 and 5 rings PAHs were given priority in water.Compared with the other domestic and oversea lakes,the PAHs pollution of the Daye Lake was at a moderate level.Source apportionment showed that the PAHs in surface sediments and water from the Daye Lake came from the combustion source,HWM-PAHs were the dominant part of the PAHs in the sediment,reflecting the sediment PAHs pollution under the effects of mining and smelting over a long period;All monomer PAHs and total PAHs content in sediment did not exceed the ERM and FEL limiting values,showing that there was no particularly serious ecological risk caused by PAHs in the surface sediments from the Daye Lake;the incremental lifetime cancer risks assessment showed that the uptake risk of PAHs in Daye Lake water through the ingestion and dermal absorption were both in the acceptable range recommended by the USEPA,but all sites had higher risk than the acceptable risk level recommended by the Sweden environmental protection agency and Royal society.The pollution of seven carcinogenic PAHs needs prevention and control.

Female streetwalkers' perspectives on migration and HIV/STI risks in a changing economic and social environment: a qualitative study in Shanghai, China.

China's 30-year economic boom has created a unique social and economic market for commercial sex, as well as for a workforce of migrant women from rural China. This qualitative study explores the impact of the rapidly changing social and economic environment on migration patterns, knowledge of sexually transmitted infections (STIs), STI risk behaviours and health beliefs among female streetwalkers in Shanghai. Qualitative data were collected in 2010 through semi-structured in-depth interviews with 16 streetwalkers to characterise their migration passages, sexual health and behaviours, and peer networks. Many streetwalkers reported histories of childhood impoverishment, of family or partner violence or trauma, of migration consistent with the timeline and routes of economic development and of a scarcity in health, social or economic support. Their knowledge of the prevention and treatment of HIV and STIs was limited. They had little bargaining power on condom use and the majority resorted to vaginal douching and self-management with antibiotics as preventative measures. The study identifies streetwalkers' perspectives on the changing environment, their options and actions and, finally, HIV/STI risks that were unique to this hidden population.