Abstract / Summary
This Literature Review is formulated with the intention to assess the dangers surrounding the detection of tar and nicotine content, specifically utilizing High Pressure Liquid Chromatography (HPLC). Also other methods to measure and evaluate the importance of these substances from a researcher's viewpoint. Attention will be primarily focused on HPLC as an important method to be utilized. Focus will also be directed at other methods used, such as taking blood samples to measure the effects of tar and nicotine. This Literature Review acknowledges the limitations of research as there are many risks regarding cigarette smoking that are relatively unknown. Moreover, much research still needs to be undertaken and solutions formulated in order for the effects of nicotine and tar to be fully understood. This paper will now discuss HPLC as a method to measure the nicotine content found within cigarette smoke.
Introduction
Literature Review. The purpose of this review is to determine the importance of the HPLC method as a way of detecting the quantity of tar and nicotine existing in cigarette smoke. In addition, a review of other methods of 'measurements', will also be evaluated.
Background. The dangers of cigarette smoking, such as disease or death have been exposed by mainstream media and anti-smoking groups and associations worldwide. This is due in part by ongoing debate regarding the risks of disease from the inhalation of cigarette smoke; both by direct inhalation and by passive inhalation. These dangers are confirmed by a quote from an article 'Exposure to Cigarette Tar Inhibits Ribonucleotide Reductase and Blocks Lymphocyte Proliferation' which discusses the implications of exposure to cigarette tar, "exposure to cigarette smoke is an established risk factor for respiratory infections and cancer and has been implicated in the progression of AIDS".1 The word 'established', suggests that the possibilities of risk from cigarette smoking are well known.
Moreover, Nicotine is an addictive substance, therefore the dangers inherent in such an addictive habit such as smoking can not be easily dismissed, as it is an addictive habit. Risks found in the 'modern' lifestyle, such as substance abuse may be harder for the individual to give up. Another article excerpt points out that, "The use of tobacco products in general and tobacco smoking is the single most preventable cause of several adverse health effects to both active and passive smokers in the world today" Montalto and Wells.2 The awareness and knowledge regarding the dangers derived from the inhalation of cigarette tar and nicotine is evident by mass sponsored and non-sponsored advertising by cigarette companies. Many countries have enacted legislation restricting the availability and utilization of cigarettes.
The importance of HPLC to detect nicotine content. Over the past decades, methods have been formulated and tested in order to provide an accurate assessment of the quantity of nicotine found within cigarettes. Scientific studies have been undertaken to ascertain if, and by how much filters on cigarettes may decrease the intake of nicotine. One study 3 into cigarette ventilation, points out that many cigarette manufacturers imply or claim lower nicotine intake due to the presence of filters. However this methodology is false due the varied smoking practices by the smokers, including either blocking or partially blocking 'vents', (minute perforated holes). In theory allowing a greater intake of air; thereby decreasing the intact of nicotine. However, in practice the smoker can partially or completely block this form of nicotine intake control. This is achieved by allowing the fingers to cover the 'vents' when holding the cigarette. The blocking of these vents, compromises the intention to reduce nicotine intake.
The reality of blocking the 'vents' is pointed out within the following article, "Our data show that the combination of ample nicotine content with filter vents that are easily, and often unconsciously defeated by smokers" Kozlowski, Mehta, Sweeney, Schwartz, Vogler, Jarvis and West.3 Therefore the utilization of this outdated methodology to measure nicotine intact is regarded as unreliable and possibly leading to false assumptions.
The High Pressure Liquid Chromatography system, is one methodology utilized to ensure that a more accurate and measurable way of ascertaining the intake of nicotine. This methodology measures the levels of nicotine in the plasma or serum. It has been the subject of much research backed-up by extensive research data. This method is widely accepted by many scientific researchers, such as confirmed by this statement, "The validity of plasma or serum cotinine concentrations as a marker and stable measure of chronic nicotine intake is well
documented" .4 Perhaps one reason why the study into the HPLC methodology is considered valid, is that it is conducted scientifically under controlled conditions with pre-determined factors and objectives.
The participants are required to comply within pre-determined conditions, such as smoking cessation studies, as can be understood by, "Applications include screening of individuals before recruitment into research studies and smoking cessation clinical trials, as an outcome marker of treatment efficacy, and for evaluation of adequacy of dosage in conjunction with nicotine replacement therapy" Jatlow et al.5 By this viewpoint, the results will be determined by conditions that can be measured accurately by non-invasive methodology. Also, the participants were recruited upon the basis that they smoked at least 20 cigarettes a day. The average participant was determined to smoke an average of 28.3 cigarettes per day, and had been smoking for an average of 23.38 years. Jatlow et al.6
Research and analysis on smokers who smoked a lot of cigarettes' in their consumption over a significant time period was conducted. This possibly enabled more accurate and measurable assumptions to be attained. Perhaps, by selecting those who smoked heavily, the researchers could get results that presented a more accurate picture regarding nicotine intake.. The testing and analysis (including taking urine samples) took place both during the temporary cessation of smoking and also when testing during normal smoking practice.
Different experiments utilizing the HPLC methodology. One of the experiments 'Pulmonary T cell responses' utilized was the enactment of measuring the tar found in cigarettes. The motivation behind this experiment was due to the effect that smoking has on the "profound suppression of pulmonary T cell responses" and that it was established by McCue et al. that the suppression of these pulmonary T cell responses led to "increased susceptibility to respiratory tract infections and decreased tumor surveillance" McCue et al. Cigarette tar extracts were prepared by “smoking” a single cigarette into 10 ml RPMI 1640 via a vacuum pump at 125 ml/min. In these studies low- and high-tar cigarettes were used. Measuring and analyzing the quantity of tar found in many different brands of cigarettes, more data was obtained. This enabled analysis and conclusions regarding the effects or tar on the human body. This data found that the dangers of lung disease and cancer existed in all brands of cigarettes.
Another method (Role of Arginine), was to extract blood samples by injection from "12 otherwise healthy male current smokers (defined as _20 cigarettes per day) and 10 male non-smokers for the determination of plasma levels of arginine, citrulline,N-hydroxy-L-arginine (NOHA), and asymmetrical dimethylarginine (ADMA). No subject received any medication".7 In this study, the process was limited to only males participating, and Zhang et al. states that the study was conducted to study the effect of smoking on cerebrovascular issues and coronary artery disease. They found that the effects of smoking did adversely effect cerebrovascular issues and coronary artery disease.
HPLC and other similar methods utilized to detect nicotine. HPLC has been the primary methodology evaluated in this paper. However, various other sources were also looked at and evaluated. This research looked at other similar methods utilized to test the quantity of nicotine found in smokers. One of the other recent methodologies used to measure nicotine was via a Rapid Semi quantitative Dipstick method. Here saliva was extracted (non-invasive) so as to determine "Measurement of cotinine, a primary metabolite of nicotine that has a half-life of 16 to 18 h and that can be detected in urine, saliva, or serum, provides a reliable means of determining smoking status and other tobacco product use or exposure" Montalto and Wells.8 In this test, "One hundred seventy-two individuals participated from a family practice/general medical setting" Montalto et al.9 This relatively high number of participants enabled a more comprehensive and accurate study to be enacted. This study indicates that the saliva test strip results had a sensitivity of 99% and a specificity of 96%. From this result it can be determined that the prognosis for accuracy and meaningful conclusive evidence is reliable. Utilizing the saliva test strip can be determined as a viable alternative methodology.
Another methodology (Cellular and molecular mechanisms of cigarette smoke-induced lung damage and prevention by vitamin C) utilized, was to enact the participation of guinea pigs as a means to measure the importance of Vitamin C as a combatant against the effects of smoking. This test was achieved by restricting the availability of Vitamin C in these animals in order to determine what role Vitamin C plays in the health of a human being. The validity of Vitamin C as a powerful anti-oxidant is explained as follows, "Since vitamin C is a strong antioxidant, we have also determined the modulatory effect of vitamin C for preventing the patho physiological events" Banerjee, Likening tests on pigs utilizing the testing of Vitamin C, cannot be perceived as similar to HPLC. However, what is similar is that the testing was enacted under controlled conditions, with the results scientifically measured and evaluated.
Conclusion
New medical science and new innovative technology are being discovered. Both the nature and methodology of research is also changing and evolving. Therefore, this Literature Review suggests that there are limitations on what research can accomplish. Yet, this paper suggests that the aforementioned findings do create an awareness about HPLC and other similar methodologies. This awareness may enable both the general public and the medical profession to proactively and accurately analyze the effects cigarette smoke has on society.
References
1. McCue JM, Link KL, Eaton SS and Freed BM. Exposure to Cigarette Tar Inhibits
Ribonucleotide Reductase and Blocks Lymphocyte Proliferation 1: The Journal of
Immunology, 2000, 165: 6771–6775.
2. Montalto NJ and Wells WO. Validation of Self-Reported Smoking Status Using Saliva
Cotinine: A Rapid Semi quantitative Dipstick Method: Cancer Epidemiol Biomarkers
Prev 2007;16(9). September 2007.
3. Kozlowski LT, Mehta NY, Sweeney CT, Schwartz SS, Vogler GP, Jarvis MJ and West RJ.
Filter ventilation and nicotine content of tobacco in cigarettes from Canada, the United
Kingdom and the United States: Published by Tobacco Control 1998;7:369–375.
4 - 6. Jatlow P, Mc-Kee S and O’Malley SS. Correction of Urine Cotinine Concentrations for
Creatinine Excretion: Is It Useful? Departments of 1 Laboratory Medicine and 2
Psychiatry, Yale University, New Haven, CT 06520.
7. Zhang WZ, Venardos K, Chin-Dusting J and Kaye DM. Metabolism and Oxidative Stress
Adverse Effects of Cigarette Smoke on NO Bioavailability: Role of Arginine. 2006
American Heart Association. 7272 Greenville Avenue, Dallas, TX.
8 - 9. Montalto NJ and Wells WO. Validation of Self-Reported Smoking Status UsingSaliva
Cotinine: A Rapid Semi quantitative Dipstick Method. Acordia National/Wells Fargo,
Charleston, West Virginia and Clinical Research Centers of Tennessee, PLLC, Lebanon,
Tennessee.
10. Banerjee S, Chattopadhyay R, Ghosh A, Koley H, Panda K, Roy S, Chattopadhyay D and
10 The Detection of Tar and Nicotine Content of Cigarette Smoke Extract Using HPLC
Chatterjee IB. Cellular and molecular mechanisms of cigarette smoke-inducedlung
damage and prevention by vitamin C. Dr. B. C. Guha Centre for Genetic Engineering
and Biotechnology, University College of Science, Kolkata 700019, India.
