title: Cardiovascular Benefits of Wearing Particulate-Filtering Respirators: A Randomized Crossover Trial.
abstract: Practical approaches to protect individuals from ambient particulate matter (PM) are urgently needed in developing countries. Evidence on the health benefits of wearing particulate-filtering respirators is limited.
  
  
  
  We evaluated the short-term cardiovascular health effects of wearing respirators in China.
  
  
  
  A randomized crossover trial was performed in 24 healthy young adults in Shanghai, China in 2014. The subjects were randomized into two groups and wore particulate-filtering respirators for 48 hr alternating with a 3-week washout interval. Heart rate variability (HRV) and ambulatory blood pressure (BP) were continuously monitored during the 2nd 24 hr in each intervention. Circulating biomarkers were measured at the end of each intervention. Linear mixed-effect models were applied to evaluate the effects of wearing respirators on health outcomes.
  
  
  
  During the intervention periods, the mean daily average concentration of PM with an aerodynamic diameter < 2.5 μm (PM2.5) was 74.2 μg/m3. Compared with the absence of respirators, wearing respirators was associated with a decrease of 2.7 mmHg [95% confidence interval (CI): 0.1, 5.2 mmHg] in systolic BP and increases of HRV parameters, including 12.5% (95% CI: 3.8%, 21.2%) in high frequency (HF) power, 10.9% (95% CI: 1.8%, 20.0%) in the root mean square of the successive differences, and 22.1% (95% CI: 3.6%, 40.7%) in the percentage of normal RR intervals with duration > 50 msec different from the previous normal RR interval (pNN50). The presence of respirators was also associated with a decrease of 7.8% (95% CI: 3.5%, 12.1%) in the ratio of low frequency (LF)/HF power.
  
  
  
  Short-term wearing of particulate-filtering respirators may produce cardiovascular benefits by improving autonomic nervous function and reducing BP. Citation: Shi J, Lin Z, Chen R, Wang C, Yang C, Cai J, Lin J, Xu X, Ross JA, Zhao Z, Kan H. 2017. Cardiovascular benefits of wearing particulate-filtering respirators: a randomized crossover trial. Environ Health Perspect 125:175-180; http://dx.doi.org/10.1289/EHP73.
authors: School of Public Health, Key Lab of Public Health Safety of the Ministry of Education and Key Lab of Health Technology Assessment of the Ministry of Health, Fudan University, Shanghai, China.
authors: Jingjin
authors: J
authors: Shi
authors: Zhijing
authors: Z
authors: Lin
authors: Renjie
authors: R
authors: Chen
authors: Cuicui
authors: C
authors: Wang
authors: Changyuan
authors: C
authors: Yang
authors: Jing
authors: J
authors: Cai
authors: Jingyu
authors: J
authors: Lin
authors: Xiaohui
authors: X
authors: Xu
authors: Jennifer A
authors: JA
authors: Ross
authors: Zhuohui
authors: Z
authors: Zhao
authors: Haidong
authors: H
authors: Kan
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000032:analysis*; D015415:Biomarkers; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D002319:Cardiovascular System; D002681:China; D018592:Cross-Over Studies; D005260:Female; D006339:Heart Rate; D006801:Humans; D019570:Inhalation Exposure / Q000517:prevention & control* / Q000706:statistics & numerical data; D016014:Linear Models; D008297:Male; D052638:Particulate Matter / Q000032:analysis*; D012134:Respiratory Protective Devices; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D015415:Biomarkers; D052638:Particulate Matter