Systemic biomarkers of inflammation, oxidative stress and tissue injury and repair among waterpipe, cigarette and dual tobacco smokers.

BACKGROUND: Waterpipe tobacco (WPT) smoking is associated with deleterious effects on cardio-pulmonary systems which may have adverse repercussions in pathophysiology and progression of chronic lung and cardiovascular diseases. We compared the biomarkers of systemic inflammation, lipid mediators, injury/repair and oxidative stress between groups of non-smokers (NS), exclusive WPT smokers (WPS), exclusive cigarette smokers (CS) and dual WPS and CS (DS). METHODS: Two cohorts were recruited. Cohort I consisted of WPS (n=12), CS (n=26), DS (n=10) and NS (n=25). Cohort II consisted of WPS (n=33) and NS (n=24). Plasma and urine samples were collected and analysed for various systemic biomarkers. RESULTS: Compared with NS, plasma levels of inflammatory mediators (interleukin (IL)-6, IL-8, IL1ß and tumor necrosis factor-α) were significantly higher in WPS and CS, and were further augmented in DS. Endothelial biomarkers (intracellular adhesion molecule-1, prostaglandin E-2 and metalloproteinase-9) were significantly higher in CS. Most notably, pro-resolving lipid mediator (resolvin E1) and biomarkers of immunity, tissue injury, and repair were significantly lower in WPS and CS. Urinary levels of 8-isoprostane were significantly higher in all smoking groups in cohort I, while 8-isoprostane, myeloperoxidase, receptor for advanced glycation end products (RAGE), En-RAGE and matrix metalloproteinase-9 were significantly higher in all smoking groups in cohort II. CONCLUSIONS: Biomarkers of inflammation, oxidative stress, immunity, tissue injury and repair were elevated in WPS and CS groups. Furthermore, concurrent use of WPT and cigarettes is more harmful than cigarette or WPT smoking alone. These data may help inform the public and policy-makers about the dangers of WPT smoking and dual use of tobacco products.

Waterpipe device cleaning practices and disposal of waste associated with waterpipe tobacco smoking in homes in the USA.

OBJECTIVES: To quantify postsmoking waterpipe tobacco (WPT) waste and describe postsmoking waterpipe (WP) device cleaning practices and disposal of associated waste in home settings. METHODS: We analysed data from a US convenience sample of 50 exclusive WPT smokers, mean age 25.3 years. Data were collected at a home visit during which participants smoked one WPT head and completed a self-administered questionnaire on WP cleaning practices and disposal of waste associated with WPT use. Research assistants provided and prepared a WP for participants by weighing and loading 10 g of WPT in the WP head and placing 470 mL of water in the WP bowl. At the completion of the smoking session, research assistants measured the remaining WPT and water. Descriptive analyses were performed. RESULTS: Of the 10 g of fresh WPT used for each smoking session, 70.1% (mean=7.01 g) was discarded postsmoking as waste; for each 470 mL of water used in the WP bowl, 94.3% (mean=443 mL) was discarded. WP device cleaning practices ranged from never cleaning the device to cleaning it after each smoking session. Respondents reported discarding smoked WPT residue in the trash (81.6%) or the kitchen sink (14.3%) and discarding postsmoking charcoal in the trash (57.6%), the kitchen sink (27.3%) or backyard soil (9.1%). Respondents reported discarding smoked WP water in the kitchen sink (76.5%), bathroom sink (14.7%), toilet (2.9%) and backyard soil (5.9%). CONCLUSIONS: Interventions and regulations are needed to inform proper WP device cleaning practices and disposal of waste associated with WPT use. TRIAL REGISTRATION NUMBER: NCT03253653.