From as early as their days in elementary school, most young Americans have had to come to terms with marijuana as a pervasive element in their lives. Just as nearly all adolescents have had to decide whether to drink and whether to smoke cigarettes, they also have had to decide whether to smoke marijuana. While marijuana vaping has recently increased as a means for consuming marijuana, marijuana smoking remains the dominant means for administering this drug. From a federal perspective, marijuana is undoubtedly the dominant illicit drug in U.S. society today despite the fact that as many as eighteen U.S. states and the District of Columbia have removed (as of 2021) the "illicit" characterization from the federal definition of marijuana use. From the National Survey on Drug Use and Health, it has been estimated that approximately 50 million Americans in 2020 smoked marijuana within the past year. Nearly 35 percent of individuals in the eighteen to twenty-five age group reported in 2020 having smoked marijuana in the past year. This percentage was about twice that of the percentages reported by two other age groups, those twelve to seventeen years old and those twenty-six years or older. Each year, the number of Americans who have taken up marijuana smoking for the first time increases. In 2020, approximately 2.8 million Americans had smoked marijuana for the first time. In other words, on each day in 2020, there were about 7,700 new marijuana users. One year earlier, in 2019, new initiates in marijuana smoking had increased by 3.5 million, with about 9,600 new marijuana users on each day of that year. Given that federal statutes define marijuana use as illicit drug use, it is fair to say that marijuana smoking for the vast majority of Americans represents the sole form of illicit drug-taking behavior in their lives. No other illicit substance comes close to marijuana. Yet, in terms of substance use, marijuana comes in third place far behind alcohol and tobacco. In 2020, approximately 139 million Americans drank alcohol and 52 million used tobacco products of some kind in the past month, 332 In 2020, 35 percent of high school seniors reported having used marijuana in the past year, 21 percent reported having done so in the past month, and 7 percent on a daily basis. Among eighth graders, 11 percent reported using marijuana in the past year, 6 percent in the past month, and only 1 percent on a daily basis. 333 Historically speaking, the character of present-day patterns of marijuana use in the United States has changed considerably in three important respects, as prevalence rates have increased over the years. First respect First, perceptions of risk among adolescent marijuana users have declined. In 2009, Lloyd Johnston of the University of Michigan survey reported that more than half of high school seniors regarded "regular marijuana smoking" as presenting "great risk to the user. 334 In contrast, in 2019, about one-third (31 percent) of high school seniors judged "regular marijuana smoking" as representing "great risk.*335 Hide Answer Second respect Second, the increased potency in currently available cannabis products is significantly greater than in years past. As noted earlier, a typical marijuana joint in the psychedelic era several decades ago contained approximately 1 to 2 percent THC; the average concentration has now risen above 6 percent to as high as 14 percent and, in the case of recent strains of sinsemilla, even higher levels. It is reasonable to assume that the adverse effects of chronic marijuana smoking will be more intense than the relatively mild symptoms associated with marijuana use in the past. Hide Answer Third respect Third, a growing number of synthetic cannabinoids are currently available on the street. A prominent example is known by the street name Spice or K2 (see Health Alert 7.1). Each year brings with it a new group of ingredients, some of them newly introduced drugs and others merely inventive creations from already available materials, ready to be combined with marijuana either to weaken its effects or to change the overall psychoactive result by some synergistic or other interactive effect.