Research suggests that people who used ecstasy at least 25 times had lowered serotonin levels for as long as a year after quitting. The manufacture of a pound of meth creates 5-6 pounds of toxic waste. Minnesota drug officials closed down a meth lab in 2003 being operated in a ice-fishing shack. The cookers were dumping waste into the ice hole, poisoning the lake. No one knows how many times a person can use ecstasy before becoming addicted or who's most vulnerable to ecstasy addiction. Genetic makeup, living environment, and other factors probably play a role in a person's susceptibility to addiction to any drug. Heroin is a highly addictive drug, and its use is a serious problem in America. Current estimates suggest that nearly 600,000 people need treatment for heroin addiction. Recent studies suggest a shift from injecting heroin to snorting or smoking because of increased purity and the misconception that these forms of use will not lead to addiction. | 
