We plan to study approximately 30 male college age (18 to 30 yrs) smokeless tobacco users in comparison to 30 control non-tobacco users. They will be screened by questionnaire to determine the frequency, duration, and length of use of tobacco. Blood pressures will be taken for baseline information in triplicate on three different occasions (using a Dinamap 845 XT Automatic Blood Pressure Monitor), in the abstained state (14 to 16 hours of overnight non-use of any form of tobacco) as well as for three different occasions after a day of continued use of their own brand tobacco. All measurements for the two groups will be taken at the same time of day depending on the treatments. The populations will be matched by age, height, weight, and classification of tobacco use (or non-use). Smokeless tobacco users will be further subclassified as light smokeless tobacco users (less than 1/2 can or package/week), versus moderate smokeless tobacco users (1/2 to 2 1/2 cans or packages/week) and heavy smokeless tobacco users (2 1/2 cans or packages/week or more). For baseline analysis blood samples will be taken in the abstained state (controls and smokeless tobacco users) for a Diagnostic Multichem blood analysis, blood lead and erythrocyte protoporphyrin (EP) levels for lead absorption, and blood cadmium concentration. (Roche Laboratories, North Carolina) As part of the Diagnostic Multichem analysis, measurement will be made of serum electrolytes, blood urea nitrogen (BUN), calcium, phosphorus, alkaline phosphatase, albumin, vit D, and complete clood count. Samples for lead and cadmium will be transferred into trace element suitable EDTA-containing rubber stopper evacuated glass tubes. Blood samples for lead and cadmium will be collected directly into such tubes. Along with these measurements, analysis for nicotine/cotinine levels will be made by Toxicology Associates, Columbus, Ohio. For quality control purposes, analysis of lead and cadmium will also be conducted by Smith-Kline Laboratories, Van Nuys, California. The results will take into consideration race, degree of urbanization (of place of residence), usage patterns of subjects, type of tobacco (snuff or chewing tobacco), and age of initiation of habit. In relation to lead absorption considerations, potential association with erythrocyte protoporphyrin (EP) and iron levels will be considered. With regard to cadmium levels, consideration of potential association with elevated blood pressures will be made. Effects on serum phosphorus, calcium, vitamin D, and uric acid will be considered in relation to lead and cadmium.
