重复暴露于接近环境水平的PM2.5会降低肺功能：受控人体暴露研究。
完整摘要 · 中文译文
流行病学研究已在观察性环境中提供了累积多日PM2.5暴露对健康影响的证据；然而，尚无在连续多日进行人体控制暴露研究。为评估接近环境水平的PM2.5暴露对肺功能和运动耐受性的影响，在健康人类志愿者（n = 17）中开展了一项随机、双盲控制暴露研究。暴露包括连续3天、每天4小时间歇性运动，分别暴露于清洁空气和35 μg/m3 PM2.5，两次暴露间隔至少2周。在每个暴露日的基线、暴露后（+0 h）和20 h（+20 h）测量肺量计。PM2.5暴露降低了肺功能，第2天和第3天后出现下降。第1天+0 h，FEV1无变化（-0.9%，95% CI：-2.1，0.3），第1天+20 h，FEV1无变化（-1.2%，95% CI：-2.4，0.1）。第2天+0 h，FEV1降低1.9%（95% CI：-3.1，-0.7）。该下降持续至第2天+20 h，FEV1降低1.7%（95% CI：-3.3，-0.2）。第3天+0 h，FEV1显示相似降低，为1.8%（95% CI：-3.5，-0.1）。该下降持续至第3天+20 h，FEV1降低1.7%（95% CI：-3.2，-0.1）。PM2.5暴露在第2天（-2.0 W，95% CI：-2.86，-1.08）和第3天（-2.4 W，95% CI：-3.18，-1.61）均降低了运动输出。肺功能和运动输出显示出性别修饰效应；男性在第3天+20 h时肺功能下降更大，女性在第3天后运动输出损失更大。总之，接近环境水平的PM2.5暴露引起肺功能缺陷 在持续暴露数日后仍维持，并且在停止暴露后至少持续20小时。PM2.5暴露会降低运动输出。
完整摘要 · 英文原文
Epidemiologic studies have provided evidence of health effects over cumulative days of PM2.5 exposure in observational settings; however, there have been no controlled exposure studies in humans over consecutive days. To assess the effects of near-ambient PM2.5 exposure on pulmonary function and exercise tolerance, a randomized, double-blind controlled exposure study was conducted among healthy human volunteers (n = 17). Exposure consisted of 4 h of intermittent exercise for 3 consecutive days to clean air and 35 μg/m3 of PM2.5 separated by a minimum of 2 weeks. Spirometry was measured at baseline, postexposure (+0 h), and 20 h (+20 h) after each day of exposure. PM2.5 exposure reduced lung function, with reductions after Day 2 and Day 3. At Day 1 + 0 h, FEV1 was unchanged (-0.9%, 95% CI: -2.1, 0.3), and at Day 1 + 20 h, FEV1 was unchanged (-1.2%, 95% CI: -2.4, 0.1). At Day 2 + 0 h, FEV1 was reduced by 1.9% (95% CI: -3.1, -0.7). This decrement persisted into Day 2 + 20 h, with FEV1 reduced by 1.7% (95% CI: -3.3, -0.2). At Day 3 + 0 h, FEV1 showed a similar reduction of 1.8% (95% CI: -3.5, -0.1). This decrement persisted into Day 3 + 20 h, with FEV1 down by 1.7% (95% CI: -3.2, -0.1). PM2.5 exposure reduced exercise output on both Day 2 (-2.0 W, 95% CI: -2.86, -1.08) and Day 3 (-2.4 W, 95% CI: -3.18, -1.61). Lung function and exercise output displayed modification by sex; males showed greater decrements in lung function at Day 3 + 20 h, and females had greater losses in exercise output after Day 3. In conclusion, near-ambient PM2.5 exposure elicits pulmonary function deficits, sustained after multiple days of exposure and persisting at least 20 h after cessation of exposure. PM2.5 exposure decreases exercise output.