Substance use problems in developing countries.

“Recurring economic and political crises in various parts of the world, serious environmental problems, and widespread insecurity about the future” (W1) have increased the gap between rich and poor, between countries and also within countries. What do we know about the role of substance use and the risk factors and impact of substance use problems in this context? The problems have to a large extent been stabilized in developed countries that have been exposed to substance use for decades, in contrast to many developing countries and countries with former socialist economies (2). Alcohol use is rising rapidly in some of the developing regions (W3): early onset and excessive drinking are reported; large increases in cigarette smoking are also documented (4). For illicit drugs, data are more difficult to obtain. Major increases in injecting drug use, which carries the highest health risks, are recorded: opiate injecting in eastern European countries and south and South-East Asia, and amphetamine injecting in many regions (W5). Research on social and environmental factors contributing to such increases has been less extensive in the developing world, but indicators and case studies (6, 7) direct attention to urbanization, poverty, migration, technological change, educational deficits, and vested interests in marketing substances (W8). In Asia, Africa and Latin America, urban populations increased from 16% to 50% of the total. “Increased stressors and adverse events, such as overcrowded and polluted environments, poverty and dependence on a cash economy, high levels of violence and reduced social support” (9) have deleterious consequences for mental health in general and substance use problems in particular, increasing the risk of heavy drinking. Half of the urban populations in lowand middle-income countries live in poverty, and tens of millions are homeless; 77% of Brazilian street children drink heavily. Associated with poverty are unemployment, low education and deprivation, all contributing to higher prevalences