to produce a potent entheogen in his own home, without access to sophisticated technology, equipment or chemical supplies." San Antonio's technique describes a method to grow the common edible mushroom Agaricus bisporus Because of a lack of clarity about laws about psilocybin mushrooms, retailers in the late 1990s and early 2000s commercialized and marketed them in smartshops in the Netherlands and the UK, and online. Several websites emerged that have contributed to the accessibility of information on description, use, effects and exchange of experiences among users. Since 2001, six EU countries have tightened their legislation on psilocybin mushrooms in response to concerns about their prevalence and increasing usage. In the 1990s, hallucinogens and their effects on human consciousness were again the subject of scientific study, particularly in Europe. Advances in neuropharmacology and neuropsychology, and the availability of brain imaging techniques have provided impetus for using drugs like psilocybin to probe the "neural underpinnings of psychotic symptom formation including ego disorders and hallucinations". Recent studies in the United States have attracted attention from the popular press and thrust psilocybin back into the limelight. Society and culture Legal status Advocacy for tolerance Despite being illegal in many typically Western countries, such as the UK, Australia and some US states, less conservative governments opt to nurture the legal use of psilocybin and other psychedelic drugs. In Amsterdam, Netherlands, authorities provide education and promotion on the safe use of psychedelic drugs, such as psilocybin, in an aim to reduce public harm. Similarly, religious groups like America's Uniao do Vegetal, UDV, use psychedelics in traditional ceremonies. Advocate for legalization argue there is a lack of evidence of harm, and potential use in treating certain mental health conditions. Research is difficult to conduct because of the legal status of psychoactive substances. Advocates for legalization also promote the utility of "ego dissolution" and argue bans are cultural discrimination against traditional users. Usage A 2009 national survey of drug use by the US Department of Health and Human Services concluded that the number of first-time psilocybin mushroom users in the United States was roughly equivalent to the number of first-time users of cannabis. In European countries, the lifetime prevalence estimates of psychedelic mushroom usage among young adults (15–34 years) range from 0.3% to 14.1%. In modern Mexico, traditional ceremonial use survives among several indigenous groups, including the Nahuas, the Matlatzinca, the Totonacs, the Mazatecs, Mixes, Zapotecs, and the