Analyzing 8-Oxoguanine in Exhaled Breath Condensate: A Novel Within-Subject Laboratory Experimental Study on
Natasha Shaukat1, Tarana Ferdous1, Simanta Roy1
1Department of Epidemiology, Robert Stempel College of Public Health, Florida International University, 11200 SW 8th St, Miami, FL 33199, USA.
Introduction:
This study aimed to analyze exhaled breath condensate (EBC) for 8-oxoguanine (8-oxoGua), an oxidative stress biomarker among waterpipe (WP) smokers.
Methods:
In a within-subject pre-post exposure design, thirty waterpipe smokers completed two 45 min laboratory sessions. EBC was analyzed for 8-oxoGua before and after WP smoking. Median differences between time points (pre vs. post) were assessed using the Wilcoxon sign rank test, with significance defined as p < 0.05.
Results:
The analysis included 59 WP smoking sessions. Participants had a median age of 24 years (IQR: 21-25), with 62.1% being female. Most had a bachelor's degree or less (62.1%), and over half were students (55.2%), while 34.5% were employed. The average age for first WP use was 18.6 years, with participants reporting a median of three WP smoking sessions per month. Results indicate a median increase in 8-oxoGua among participants from 5.4 ng/mL (IQR: 8.8) before the smoking session to 7.6 ng/mL after (IQR: 15.7; p < 0.001).
Conclusions:
This study is the first to examine 8-oxoGua in EBC. Findings provide strong evidence of WP smoking's contribution to oxidative stress in the airways. It justifies the use of EBC to study the exposure to markers of oxidative stress with emerging tobacco use methods such as the waterpipe.
