Hazucha Milan J, Folinsbee Lawrence J, Bromberg Philip A
Department of Medicine, School of Medicine, and the Center for Environmental Medicine, Asthma and Lung Biology, University of North Carolina, Chapel Hill, North Carolina 27599-7310, USA.
J Appl Physiol (1985). 2003 Nov;95(5):1917-25. doi: 10.1152/japplphysiol.00490.2003. Epub 2003 Jul 18.
Subjects were healthy nonsmoking men (n = 146) and women (n = 94) 18-60 yr old. Initially, each subject was exposed for 1.5 h to 0.42 ppm O3. Forty-seven individuals were later reexposed twice, 1 wk to several months apart, to 0.4 ppm O3. Intermittent exercise utilized in all exposures was adjusted to produce an O3 dose of 560 ppm x l/m2 body surface area. The post-O3 percent change in forced-expiratory volume in 1 s (delta%FEV1) decrements of young (18-35 yr) and middle-aged (36-60 yr) men and women differed significantly (P < 0.05) from normal distribution with values skewed toward larger decrements in younger subjects. The mean delta%FEV1 rates were -16.3%, -16.6%, -11.6%, and -6.4%, respectively. The rate of decline with age was 2.5 times higher in young women compared with young men (P < 0.05). This pattern was reversed in the middle-age cohort. Our data support earlier reports of no significant difference in spirometric response to O3 between young men and women. The data also confirm that large FEV1 decrements after O3 exposure are mostly confined to younger individuals that also show much greater variance in response to repeated exposures than the middle-aged subjects. The majority of subjects remained in their initial category of O3 sensitivity on retesting after various time lapses. The r value (Spearman) between the first and second and first and third exposure response ranged from 0.544 to 850, depending on classification. However, the mean delta%FEV1 differed by as much as six percentage points between exposure days. The yearly loss of responsiveness (0.2% to 0.7%/year) with progressing age determined by cross-sectional analyses was substantially smaller.
受试者为18至60岁的健康非吸烟男性（n = 146）和女性（n = 94）。最初，每位受试者暴露于0.42 ppm的臭氧中1.5小时。47名个体随后在1周至数月的间隔内再次暴露于0.4 ppm的臭氧中两次。所有暴露过程中采用的间歇性运动经过调整，以产生560 ppm×l/m²体表面积的臭氧剂量。臭氧暴露后1秒用力呼气量（delta%FEV1）的下降百分比，年轻（18至35岁）和中年（36至60岁）男性和女性与正态分布有显著差异（P < 0.05），数值偏向年轻受试者中更大的下降幅度。平均delta%FEV1率分别为-16.3%、-16.6%、-11.6%和-6.4%。年轻女性的下降率比年轻男性高2.5倍（P < 0.05）。这种模式在中年人群中相反。我们的数据支持了早期关于年轻男性和女性对臭氧的肺量计反应无显著差异的报道。数据还证实，臭氧暴露后FEV1的大幅下降主要局限于年轻个体，而且与中年受试者相比，年轻个体对重复暴露的反应差异也大得多。大多数受试者在经过不同时间间隔重新测试后，仍处于其最初的臭氧敏感性类别。根据分类，第一次与第二次以及第一次与第三次暴露反应之间的r值（Spearman）在0.544至0.850之间。然而，暴露日之间的平均delta%FEV1差异高达6个百分点。通过横断面分析确定的随着年龄增长每年反应性的损失（0.2%至0.7%/年）要小得多。
