Clinical trial Recruiting at 1 site Interventional Ages 21 and up

Charcoal-filtered versus regular cigarette filters: effects on perceptions, smoking, and exposure

Official title: A Randomized Trial of Charcoal-filtered Cigarettes on Product Perceptions, Smoking Behaviors, and Toxicant Exposure

Run by Rutgers, The State University of New Jersey · NCT07348679 · Data updated 2026-11-12

This trial will test whether using charcoal-filtered versus regular cigarette filters changes what adult smokers think of the product, how they smoke, and their exposure to harmful chemicals.

Quick facts

Study typeInterventional
Ages21 Years and up
SexAll
Enrollment252 (estimated)
SponsorRutgers, The State University of New Jersey
Academic / other
Locations1 site (New Brunswick, New Jersey)
StatusRecruiting
StartedApril 27, 2026
Main results expectedDecember 31, 2030
Study endsDecember 31, 2030
Registry record updatedJune 5, 2026
Trial IDNCT07348679 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults aged 21 or older who smoke at least 5 cigarettes per day, primarily use non-menthol brands other than Natural American Spirit, are not trying to quit, and can attend weekly lab visits in English are ideal candidates.

Probably not a fit

People who primarily use menthol or Natural American Spirit cigarettes, are enrolled in or planning to join a quit program, are under 21, or cannot attend in-person weekly visits are unlikely to benefit or be eligible.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a 5-week, open-label, parallel-design randomized trial in adult daily smokers. After a baseline period smoking their usual brand, participants are randomized to smoke cigarettes with charcoal filters (with or without marketing) or non-charcoal filters for four weeks. Participants come weekly to a laboratory session to smoke two cigarettes under observation, provide urine and carbon monoxide samples, and complete questionnaires on perceptions and behavior. Primary outcomes include product perceptions, smoking behavior measures, and biomarkers of exposure to tobacco-related toxicants.

Why it matters

Potential benefit: If successful, the results could show whether charcoal filters reduce exposure to toxicants or change smoking behavior, informing product design and regulation that might lower harm for smokers.

How similar studies have gone: Prior small laboratory studies of charcoal or novel filters have shown mixed and limited evidence for reducing exposure or changing behavior, so this approach is not yet proven.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Eligible subjects will be:

  1. Male and female smokers who are at least 21 years of age and self-report smoking at least 5 cigarettes per day for at least the past 6 months.
  2. Smokers of primarily non-menthol cigarettes of brands other than Natural American Spirit.
  3. Not currently undergoing smoking cessation treatment or trying to quit.
  4. Able to communicate fluently in English (speaking, writing, and reading).
  5. Capable of giving written informed consent, which includes compliance with the requirements and restrictions listed in the combined consent and HIPAA form.

Exclusion Criteria:

* Subjects who self-report and/or present with the following criteria will not be eligible to participate in the study:

Smoking Behavior

1. Use of menthol or Natural American Spirit cigarettes as preferred/regular brand (defined as using \>20% of the time).
2. Enrollment or plans to enroll in a smoking cessation program in the next month.
3. Provide an initial Carbon Monoxide (CO) reading \< 5 parts per million (ppm).

Alcohol/Drugs

1. History of substance abuse (other than nicotine) in the past 12 months and/or currently receiving medical treatment for substance abuse.
2. Current alcohol consumption that exceeds 25 standard drinks/week.

Medical

1. Women who are pregnant, planning a pregnancy, and/or lactating.
2. Any impairment including, but not limited to, visual, physical, and/or neurological impairments preventing the completion of procedures included within this protocol. Notable impairments will be evaluated by the PI and eligibility will be determined on a case-by-case basis.
3. Color blindness.
4. Serious or unstable disease within the past 12 months (e.g. heart disease, cancer). Applicable conditions will be evaluated by the Principal Investigator and eligibility will be determined on a case-by-case basis.

Psychiatric

As determined by self-report:

1. Lifetime history or current diagnosis of psychosis, bipolar disorder, and/or schizophrenia.
2. Current diagnosis of major depression. Subjects with a history of major depression, in remission for 6 months or longer, are considered eligible.

Other

Additionally, participants may be deemed ineligible for any of the following general reasons at any point throughout the study, as well as during the initial telephone screen, at the discretion of the PI:

* Significant non-compliance with protocol and/or study design.
* Past, current, anticipated, or pending enrollment in another research program over the study period that could potentially impact study data.
* Any medical condition, illness, disorder, adverse event (AE), or concomitant medication that could compromise participant safety or significantly impact study performance.

Where it's running

  • Institute for Nicotine and Tobacco Studies
    New Brunswick, New Jersey, United States
    Recruiting

Study contacts

  • Principal investigator: Melissa Mercincavage, PhD — Rutgers, The State University of New Jersey
  • Study coordinator: Matthew Joy, MPH
  • Email: maj206@ints.rutgers.edu
  • Phone: 848-267-8284

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.