Melanin and Dermal Uptake of Thirdhand Cigarette Smoke (THS05)

This is a pilot study of the effects of dermal melanin on dermal uptake and retention of nicotine. The initial hypothesis is that higher levels of dermal melanin will correlate with lower uptake and longer retention of nicotine in the skin and body.

Study Overview

• Status: Not yet recruiting
• Conditions: Healthy
• Intervention / Treatment: Other: Wear clothing that has been exposed to cigarette smoke for 3 hours.

Detailed Description

This is an interventional pharmacokinetic study comparing the uptake and metabolism of nicotine from smoke-exposed clothing in people with low high levels of dermal melanin and people with high levels of dermal melanin. The study will measure nicotine and metabolites of nicotine in the blood during exposure and in urine for 10 days after exposure.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Suzaynn F Schick, PhD; Phone Number: 415-514-3535; Email: suzaynn@gmail.com
• Study Contact Backup: Name: Abel Huang, BS; Phone Number: (415) 514-9011; Email: abel.huang@ucsf.edu

Study Locations

• United States
  • California
    • San Francisco, California, United States, 94110
      • Zuckerberg San Francisco General Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Adult nonsmoker
• Aged 18-50
• Skin reflectance scores below 150 or above 249 using the Mexameter 18 instrument
• Healthy on the basis of medical history
• Systolic blood pressure <150
• Diastolic blood pressure <100
• C-reactive protein <3.1 mg/ml
• Liver function (AST and ALT) in normal ranges
• kidney function (BUN) in normal ranges
• LDL<131
• Blood glucose <110
• Not exposed to tobacco SHS.

Exclusion Criteria:

• Dermal skin reflectance score between 150 and 249, as measured by the Mexameter 18 instrument.
• Positive SARS-CoV-2 antibody test
• Age 18 < or > 50
• Physician diagnosis of asthma, heart disease, hypertension, thyroid disease, diabetes, renal or liver impairment or glaucoma.
• Unstable psychiatric condition (such as current major depression, history of schizophrenia or bipolar disorder) or current use of more than two psychiatric medications
• Systolic blood pressure greater than or equal to 150
• Diastolic blood pressure greater than or equal to 100
• Blood glucose greater than or equal to 110
• LDL greater than or equal to130
• Pregnancy or breastfeeding (by urine hCG and/or history)
• Alcohol or illicit drug dependence within the past 5 years
• BMI > 35 and < 18
• Current illicit drug use (by history or urine test)
• More than 1 pack year smoking history
• Ever a daily marijuana smoker
• Smoked anything within the last 3 months
• Unable to hold allergy or other OTC medicines
• Occupational exposure to smoke, dusts OR fumes
• Concurrent participation in another clinical trial
• Unable to communicate in English
• No social security number

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Low melanin; Individuals with skin reflectance scores below 150 using the Mexameter 18 instrument.	Other: Wear clothing that has been exposed to cigarette smoke for 3 hours.; Cotton clothing is exposed to smoke from Marlboro Red (hard pack) cigarettes at 1-1.2 mg/m3 repeatedly, until total exposure equals 3 grams total particulate material. When tested after exposure, the clothing typically contained 59.15 +/- 18 µg nicotine and 42 +/- 24 ng NNK per gram. The mass of the clothing varies by size, but the average combination of pants and shirt contains 32 mgs nicotine and 23 µg NNK.
Experimental: High melanin; Individuals with skin reflectance scores above 249 using the Mexameter 18 instrument	Other: Wear clothing that has been exposed to cigarette smoke for 3 hours.; Cotton clothing is exposed to smoke from Marlboro Red (hard pack) cigarettes at 1-1.2 mg/m3 repeatedly, until total exposure equals 3 grams total particulate material. When tested after exposure, the clothing typically contained 59.15 +/- 18 µg nicotine and 42 +/- 24 ng NNK per gram. The mass of the clothing varies by size, but the average combination of pants and shirt contains 32 mgs nicotine and 23 µg NNK.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Total combined urinary concentrations of the nicotine metabolites cotinine and 3-hydroxycotinine	The study will measure urinary metabolites of nicotine in the first void of the day for 10 days after exposure and sum the total mass of metabolites.	First void, collected for 10 days
Change in blood concentrations of nicotine	The study will measure concentration of nicotine in the blood before and after the dermal exposure to nicotine.	Baseline and 3 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Urinary concentration of the NNK metabolite NNAL	The study will measure urinary metabolites of NNK in the first void of the day for 10 days after exposure and sum the total mass of metabolites.	First void, collected for 10 days

Collaborators and Investigators

• Sponsor: University of California, San Francisco
• Investigators: Principal Investigator: Suzaynn F Schick, PhD, University of California, San Francisco

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2023
• Primary Completion (Estimated): November 1, 2025
• Study Completion (Estimated): November 1, 2025

Study Registration Dates

• First Submitted: August 25, 2023
• First Submitted That Met QC Criteria: August 25, 2023
• First Posted (Actual): August 31, 2023

Study Record Updates

• Last Update Posted (Estimated): September 6, 2023
• Last Update Submitted That Met QC Criteria: September 1, 2023
• Last Verified: September 1, 2023

More Information

Terms related to this study

• Keywords: Nicotine; Exposure; Dermal; Melanin; Thirdhand tobacco smoke; Tobacco Smoke Pollution
• Other Study ID Numbers: 22-37861

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No