Study On Determination Of Trace Elements And Heavy Metals In Tobacco

The issue on smoking and health has always been greatly concerned about. In 1964, the first Surgeon General's Report on Smoking and Health was published by the United States Department of Health, Education, and Welfare. The report revealed that cigarette smoking is directly related to illness and death from heart disease and other ailments; that cigarette smoking is one of the leading contributory cause of death from chronic bronchitis and other lung disorders. The World Health Organization (WHO) also points out that the use of tobacco has great relations with death and prevalence of diseases, which is expanding increasingly over the world; that cigarette smoking is one of the major reasons which result people disability and early death. However, it is impossible to fully prohibit smoking at present. Since tobacco will exist at present and during a long time of future, it is very necessary for people to explore methods and means of reducing tobacco harm.Some countries such as America, Britain and former Soviet Union have carried out studies on trace elements in tobacco plant since 1930's ~ 1940's. Chinese experts started the research work on trace elements and heavy metals in tobacco in 1980's. The study on determination of trace elements and heavy metals in tobacco has already been carried out using different sample preparation and detection methods by many experts. Nowadays, the creation of standard, fast and accurate methods for determining trace elements and heavy metals in tobacco is one of the imperative research subjects of the tobacco industry.In this thesis, the methods for determination of trace elements and heavy metals in tobacco is summarized. Then, the inductively coupled plasma mass spectrometry (ICP-MS) is introduced. Some important advances and recent status in ICP-MS have also been outlined. The tobacco sample is digested thoroughly in a closed-vessel microwave digestion system with nitric acid and hydrogen peroxide, and the trace elements and heavy metals are fully extracted from the matrix. Meanwhile, the loss of volatile elements such as mercury, arsenic and lead is avoided. The simultaneousness determination methods for 6 elements (Ti, Sr, Mo, Ba, Th and U) and 27 elements (Be, Na, Mg, K, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Sr, Mo, Ag, Cd, Sn, Cs, Ba, Hg, T1, Pb, Th and U) are studied. The studies for 7 elements (Cr, Ni, As, Se, Cd, Hg and Pb) and 17 elements (Be, Ti, V, Cr, Ni, Cu, As, Sr, Mo, Ag, Cd, Cs, Ba, T1, Pb, Th and U) are also carried out, focusing on the determination method and the level of elemental content in different samples.