asthma, and 790,000 health care visits for ear infections. The addictive alkaloid nicotine is a stimulant, and popularly known as the most characteristic constituent of tobacco. In drug effect preference questionnaires, a rough indicator of addictive potential, nicotine scores almost as highly as opioids. Users typically develop tolerance and dependence. Nicotine is known to produce conditioned place preference, a sign of psychological enforcement value. In one medical study, tobacco's overall harm to user and self was determined at three percent below cocaine, and 13 percent above amphetamines, ranking sixth most harmful of the 20 drugs assessed. Radioactivity Polonium-210 is a radioactive trace contaminant of tobacco, providing additional explanation for the link between smoking and bronchial cancer. The radioactive particles build up over time in the lungs and a UCLA study has estimated that the radiation from 25 years of smoking would cause over 120 deaths per thousand smokers. Economic Tobacco has a significant economic impact. The global tobacco market in 2010 was estimated at US$760 billion, excluding China. The global revenues from tobacco taxes in 2013-2014 was approximately $269 billion. In China, cigarette manufacturing is one of the few profitable state-owned industries. For example, in 1998 the 1 429 state-owned enterprises in Yunnan province had revenue of Renminbi (RMB) 69.1 billion (US$8.3 billion) while 8 cigarette manufacturing plants alone accounted for about 53 percent (or RMB 36.2 billion) of total provincial industry sales. The Chinese government also collects tax on tobacco products. Tax revenues from cigarettes increased from 740 to 842 billion Chinese yuan between 2014 and 2016. This generated an additional 101 billion Chinese yuan in tax revenues for the government. In India, tobacco generates approximately 20 billion Indian Rupees (US$0.45 billion) of income per annum as a result of employment, income and government revenue. Statistica estimates that in the U.S. alone, the tobacco industry has a market of US$121 billion, despite the fact the CDC reports that US smoking rates are declining steadily. In terms of health expenditures, cigarette smoking contributed to more than $225 billion (or 11.7%) of annual healthcare spending in the U.S. in 2014. Smoking-attributable healthcare spending increased more than 30% for Medicaid between 2010 and 2014. In the US, the decline in the number of smokers, the end of the Tobacco Transition Payment Program in 2014, and competition from growers in other countries, made tobacco farming economics more challenging. Of the 1.22 billion smokers