Identification and seasonal variation of specific particulate bound (halogenated) polycyclic aromatic hydrocarbons in air from different metal industrial parks in Northwest China.

During the process of industrial heating, a large amount of polycyclic aromatic hydrocarbons (PAHs) and their halogenated compounds (Cl/Br-PAHs) can be formed. However, there is still limited understanding of the chemicals from different metal smelting industrial parks. This study evaluated the seasonal variations, composition profiles, and source allocations of the atmospheric particulate-bound PAHs and Cl/Br-PAHs in different metal industrial parks in a typical industrial city in northwest China. The results showed that the main PAHs produced by metal smelting were low molecular weight isomers, and the concentrations of Cl-PAHs were lower compared to Br-PAHs. The main Br-PAHs were 1-Br-Pyr and 4-Br-Pyr, while 9-Cl-Fle, 1-Cl-Pyr, and 6-Cl-BaP were the dominated Cl-PAH isomers. No significant difference was found in the concentrations among the sites, whereas the levels of the target chemicals were higher during cold months compared to warm months. The main source of PAHs was coal combustion and gasoline vehicle emission during metal smelting, and that of Cl/Br-PAHs was also industrial coal burning. In addition to the primary source, the secondary chlorination of parent PAHs was also a significant source of Cl-PAHs in the production of high purity aluminum. This study suggests that Cl-PAHs and Br-PAHs may behave differently in the atmosphere.

The effectiveness of an online sexuality education module in promoting sexual knowledge and attitude change: a cluster randomized controlled trial.

This study assesses the ability of an online sexuality education (OSE) module ('You and Me') to enhance sexual and reproductive health (SRH) knowledge and attitudes among 10th-grade vocational high school students in China. We conducted a cluster randomized controlled trial, randomizing 29 vocational high schools to (i) receiving the module (intervention) or (ii) not receiving the module (control). Students completed a baseline questionnaire, then completed the module within 8 weeks and then completed a follow-up questionnaire within the following 2 weeks. We assessed the differences in intervention effects using hierarchical linear modeling. No significant differences between intervention and control groups were found for knowledge and attitude scores at baseline among the 2985 students included in the analyses. For the intervention group at follow-up, we observed significant improvements in SRH knowledge scores of approximately 20% for boys and girls although girls responded to the module with larger knowledge gains than boys. At follow-up, intervention group students also had higher SRH attitude scores toward views that are more contemporary than the control group. In addition, girls held more contemporary attitudes than boys. The comprehensive OSE module assessed is effective in improving SRH knowledge, and attitude among Chinese vocational high school students after the module is completed.

Epidemiological characteristics of injuries among middle school students in Zhongshan, Guangdong Province / 中国学校卫生

Objective@#To explore the epidemiological characteristics of injury among middle school students in Zhongshan city, Guangdong Province, and to provide evidence for appropriate student injury prevention strategies and injury monitoring programs.@*Methods@#The cluster random sampling method was used to collect injury information among 2 212 middle school students in urban and suburban areas of Zhongshan city. SPSS 22.0 was used for statistical analysis.@*Results@#Among all the 2 212 middle school students, the incidence of injury was 17.95%. The incidence of injuries (20.9%)and mutiple injuries(6.67%)among boys was higher than that of girls(15.42%,4.61%),and the differences were of statistical significance(χ2=11.21,4.45,P<0.05). The incidence of multiple injuries among junior high school students(6.70%) was higher than that among high school students(4.48%)(χ2=5.20，P<0.05). The injury occurred in the school (63.76%) was higher than that occurred outside of the school (36.24%). Most injures were more likely to occur in sports area in school(33.16%),and most injuries were found occured while doing physical activities(38.01%).@*Conclusion@#The prevention of injury among middle school students should focus on junior high school students and male students. School-based injury prevention and health education should focus on campus sports-related injury.