Waterpipe (WP) smoking has become one of the leading tobacco use methods among youth in Florida. The impact of this dramatic rise is amplified by the mounting evidence of WP addictive and harmful nature, as well as the lag of policy response to it. Evidence suggests WP use leads to nicotine addiction, and increases the risk of lung cancer, heart and respiratory disease and exposure to secondhand smoke. The spread of WP use among youth has been fueled by a misperception of reduced-harm compared to cigarettes. Health Warning Labels (HWLs) represent one of the most successful tobacco control strategies to communicate smoking- related risks, and studies have consistently shown that HWLs are associated with a decrease in smoking rates and smoking-related morbidity and mortality. Therefore, communicating WP risks to young people through HWLs has been identified as a priority by major health bodies in the US including the FDA.

Using the Delphi method among international tobacco control experts, our team has developed a set of 12 WP HWLs corresponding to 4 health themes; health risks/addiction, harm to others, WP-specific harm, WP harm compared to cigarettes. Building on this work, and using a mixed- method approach incorporating qualitative and quantitative research, the investigators propose to:

Aim 1: Adapt the 12 HWLs to young WP smokers in Florida using exploratory focus groups.

Aim 2: Test in a clinical lab experiment the performance of the top 4 HWLs on the WP device compared to no-HWL/control on harm perception, intention to quit, and toxicant exposure (Carbon monoxide (CO), nicotine, oxidative stress).

Aim 3: Use the knowledge obtained to advocate for the adoption of WP-HWLs policies and disseminate information about WP harmful effects to young people in Florida and nationally.

Communicating WP risks through HWLs promises to reduce WP use and WP-related morbidly and mortality among young adults in Florida. This pioneering work will inform the FDA and public health advocates on the potential of WP-HWLs policies and provide a model for other states to respond to the WP epidemic.

Our Team developed 12 pictorial Health Warning Labels (HWLs) for the waterpipe (WP) corresponding to 4 themes; health risks/addiction, harm to others, specific harm, and harm compared to cigarettes. The investigators will build on this work to advance HWLs policies and disseminate knowledge about WP harmful effects to young people in Florida and nationally through the following specific aims:

1. Adapt the HWLs to young adults in Florida using focus groups. The investigators will conduct mixed- gender focus groups combined with brief survey with regular WP smokers (6-8 groups; n ≈ 65; age 18-29 yrs) to 1- adapt the 12 HWLs to our target population, 2- explore their optimal placement and size, and 3- select the top 4 HWLs for testing (Aim 2).
2. Test the top 4 HWLs in a clinical lab experiment. Using the top 4 HWLs on the device, the investigators will recruit 2 groups of WP smokers (n= 248; age 18-29 yrs) based on their use frequency (beginners, established) for a within- (HWL vs no-HWL; pre- vs post- smoking) and between-subject (beginner vs. established; 4 HWLs) experiment. Participants will be randomly assigned to one of the 4 HWLs conditions and undergo 2 smoking sessions that differ by HWL (HWL vs. no-HWL), with pre-post smoking assessment of harm perception, intention to quit, and toxicant exposure. Participants will receive a follow-up phone call 3- month after exposure to assess longer-term changes in quit attitude and behavior. The investigators hypothesize that applying pictorial HWLs to the WP device will; 1- significantly increase harm perception and intention to quit, and reduce puffing behavior, satisfaction, and exposure to toxicants compared to no-HWL; 2- this effect will be more pronounced in beginner than established smokers.
3. Disseminate knowledge. The investigators will partner with Tobacco-Free Workgroup, and Truth Initiative to advocate for the adoption of HWLs policies and disseminate knowledge about WP harmful effects to young people in Florida and nationally.

Impact: Communicating WP risks through HWLs promises to reduce WP use and WP-related morbidly and mortality among young adults in the US.

Inclusion Criteria:

• Age of 21-35 years.
• Beginners WP smokers (defined as started WP smoking in the past 6 months, but smoke WP less than weekly); or established WP smokers (defined as smoked at least once a week in the past 6 months).
• Generally healthy individuals (determined by physical examination).
• Is willing to provide informed consent.
• Is willing to attend the lab as required by the study protocol.
• Have abstained from WP for 12 hours prior to each lab session.

Exclusion Criteria:

• Women who are breast-feeding or test positive for pregnancy (by urinalysis at screening).
• Individuals with self-reported history of chronic disease or psychiatric conditions.
• Individuals with history of or active cardiovascular disease, low or high blood pressure, seizures, and regular use of prescription medications (other than vitamins or birth control).
• Report tobacco product use regularly (> 5 times/month in the past year).