Controlled Exposure of Healthy Nonsmokers to Secondhand and Thirdhand Cigarette Smoke
Controlled Exposure of Healthy Nonsmokers to Secondhand and Thirdhand Cigarette Smoke
This study compares the health effects of dermal and inhalational exposure to thirdhand
 cigarette smoke to those of inhalational exposure to secondhand cigarette smoke in healthy,
 adult nonsmokers. Our hypothesis is that dermal exposure increases exposure to the tobacco
 specific carcinogen, NNK and may affect both endothelial function and epidermal integrity.
Thirdhand cigarette smoke is the smoke chemicals that persist in the environment after
 smoking. Indoors, they can be found both on surfaces and in the air. Thirdhand smoke derives
 from secondhand smoke and contains the chemicals that stick to surfaces, are re-emitted into
 the air and that form by chemical reactions both on surfaces and in the air.

 Thirdhand smoke can contain higher concentrations of the tobacco-specific nitrosamine and
 known carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) than secondhand smoke,
 because nicotine reacts to form NNK in the indoor environment. Dermal exposure to thirdhand
 smoke includes nicotine, NNK and other tobacco-specific nitrosamines, polycyclic aromatic
 hydrocarbons, and volatile organic compounds. Inhalational exposure to thirdhand smoke
 includes nicotine, ultrafine particles and volatile organic compounds. Previous studies have
 shown that inhalational exposure to secondhand cigarette smoke causes endothelial
 dysfunction, which is a risk factor for heart disease and heart attacks.
Inclusion Criteria:

 -  Healthy on the basis of medical history, blood pressure and test of C-reactive
 protein, lipids and blood sugar.

 -  Non-smoker not exposed to second-hand smoke (SHS) as determined by saliva cotinine <
 10 ng/ml and tetrahydrocannabinol (THC) < 50 ng/ml.

 -  Flow mediated dilation of 4% or greater at screening visit.

 Exclusion Criteria:

 -  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 > 150 Diastolic blood pressure > 100 Blood glucose > 110 LDL >130 Pregnancy or
 breastfeeding (by urine Human Chorionic Gonadotropin (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
 over-the-counter (OTC) medicines Occupational exposure to smoke, dusts and fumes Concurrent
 participation in another clinical trial Unable to communicate in English No social security
 number