Cigarette Filter Study

BEHAVIORAL

Charcoal filtered cigarettes with marketing

After completing a 7-day baseline period of smoking their own preferred brand, participants randomized to the charcoal filtered cigarette with marketing condition will use Natural American Spirit Sky cigarettes for the next 28 days

BEHAVIORAL

Charcoal filtered cigarette without marketing

After completing a 7-day baseline period of smoking their own preferred brand, participants randomized to the charcoal filtered cigarette without marketing condition will use Tareyton cigarettes for the next 28 days

BEHAVIORAL

Non-charcoal filtered cigarettes

After completing a 7-day baseline period of smoking their own preferred brand, participants randomized to the non-charcoal filtered cigarette condition will use Natural American Spirit Yellow cigarettes for the next 28 days

Risk beliefs

Time frame: Day 35

Risk beliefs will be captured via 8 items rated on a 5-point Likert scale (1 = "definitely untrue", 5 = "definitely true") that evaluate participants' preferred brand and the cigarettes they smoke on the following beliefs: a) "lower in nicotine", b) "lower in tar", c) "less addictive", d) "less likely to cause cancer", e) "has fewer chemicals", f) "is healthier", g) "makes smoking safer", h) "helps people quit smoking." Individual items will be scores as correct or incorrect, and incorrect responses will be summed to created an overall false beliefs score (0-8 range, with higher scores indicating greater false beliefs about reduced risk.

Perceived health risks

Time frame: Day 35

Participants will indicate on a 7-point Likert scale (1 = "very low risk", 7 = "very high risk") their risk of developing smoking-related health conditions (i.e., lung cancer, heart disease, stroke, emphysema, respiratory infections, and other cancers) from regular use of the cigarette they are smoking. Higher mean scores indicate greater perceived risk (range 1-7).

Subjective ratings

Time frame: Day 35

Participants will rate cigarettes smoked during in-person visits using 14 individual items assessing various cigarette characteristics (e.g., strength, taste, satisfaction, harshness) used by the tobacco industry and our laboratory. Items are rated on a 100 mm visual analog scale with item-specific anchors (e.g., strength: 0 = "very weak," 100 = "very strong"); lower scores indicate less favorable ratings. We will examine mean composite scales generated from these items to assess domains of product harshness, smoking satisfaction, positive sensory experience, and cleanliness.

Daily cigarette consumption

Time frame: Day 35

Daily cigarette consumption will be assessed by participant self-report and verified through collection of used filters for all cigarettes smoked during the 5-week study. The mean will be computed for daily cigarette consumption during the week preceding final study session (i.e., mean of cigarettes smoked per day between Sessions 5 and 6, or Days 28-35).

Smoking topography (puffs taken)

Time frame: Day 35

We will use a validated procedure to score video recorded smoking sessions to quantify puffing behavior to obtain estimated number of puffs taken.

Smoking topography (total duration)

Time frame: Day 35

We will use a validated procedure to score video recorded smoking sessions to quantify puffing behavior to obtain estimates of the duration of each puff, and sum these to create a summary composite measure (in sec).

Smoking topography (total interpuff interval)

Time frame: Day 35

We will use a validated procedure to score video recorded smoking sessions to quantify puffing behavior to obtain estimates of interpuff interval (i.e., time between puffs) and created a summed composite (in sec).

Session onset carbon monoxide (CO)

Time frame: Day 35

CO will be assessed in ppm using the coVita Micro+ pro Smokerlyzer breath CO monitor (Santa Barbara, CA) at session onset to estimate daily tobacco exposure.

Carbon monoxide (CO) boost

Time frame: Day 35

CO will be assessed in ppm using the coVita Micro+ pro Smokerlyzer breath CO monitor (Santa Barbara, CA) before and after each cigarette smoked. The change in CO resulting from smoking a cigarette, CO boost, estimates exposure due to smoking an individual cigarette.

Tobacco/nicotine exposure

Time frame: Day 35

Total nicotine equivalents exposure will be assessed via measuring urine concentrations of nicotine metabolites by liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) using Waters Xevo® TQ-XS Tandem Mass Spectrometer with ACQUITY UPLC I-Class Chromatography System (UPLC-MS-MS). Greater values indicate greater exposure.

NNAL exposure

Time frame: Day 35

We will assess NNAL (4-(Methylnitrosamino)-1-(3-pyridyl)-1-butanol), a metabolite of NNK (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone), a potent lung carcinogen. A highly sensitive UHPLC-MS/MS method with Waters Xevo® TQ-XS UPLC-MS-MS will determine total NNAL in urine using liquid-liquid extraction followed by conversion to the hexanoate ester derivative. Greater values indicate greater exposure.

VOC exposure

Time frame: Day 35

We will collect a urine sample to assess exposure to seven volatile organic compounds (VOCs) due to their association with adverse health effects such as cancer, birth defects, and neurological damage S-(3-hydroxypropyl)-mercapturic acid (3HPMA, a metabolite of potentially toxic acrolein; 2-Carbamoyl-2-hydroxy-ethyl mercapturic acid (2CAHEMA, a metabolite of a neurotoxicant acrylamide); 2-carbamoyl-2-hydroxy-ethyl mercapturic acid (2CYEMA, a metabolite of a potent respiratory irritant acrylonitrile); phenyl mercapturic acid (PHMA, a metabolite of IARC Group 1 carcinogen benzene); benzyl mercapturic acid (BZMA, a metabolite of IARC Group 3 carcinogen toluene); 2,4-Dimethylphenyl mercapturic acid (24MPHMA, a metabolite of IARC Group 3 carcinogen xylene); and N-Acetyl-S-(4-hydroxy-2- buten-1-yl)-L-cysteine (MHBMA3, a metabolite of 1,3-Butadiene).

What is a clinical trial?

A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.

Is it safe to participate?

Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.

Will I be compensated?

Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.

Will I receive a placebo instead of treatment?

When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.

Can I leave a trial if I change my mind?

Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.

How long does a clinical trial last?

Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.