Cocaine from drains in Spain.

Researchers have documented the flow of so-called drugs of abuse, such as cocaine, methamphetamine, and ecstasy, in rivers and streams from Venice, Italy, to Florence, Ore. However, new research published in ES&T (DOI 10.1021/es800768h) shows that conventional drinking-water treatment successfully removes these drugs and others considered to be more benign, such as caffeine and nicotine. The researchers, from the University of Barcelona and the water corporation Grupo Agbar, tested water samples for a suite of illicit drugs that included PCP, LSD, cocaine, ecstasy, and methamphetamine, as well as several metabolites. They also looked for caffeine and nicotine; nicotine recently has shown promise as a biomarker of human activity (Environ. Sci. Technol. 2008, DOI 10.1021/es800455q). Led by Francesc Ventura of Grupo Agbar, the team monitored the Llobregat, a highly polluted river in Spain, and several of its tributaries. Drugs can be detected in the treated wastewater that is dumped into these water bodies by more than 55 treatment plants. To track the contamination, the team sampled river water at more than a dozen input sites during different seasons throughout a year. The researchers also took spot samples at the same time every day for a week in December at a treatment plant that provides drinking water for 1 million people. They followed up with a year of regular monitoring. The researchers found that the river basin is basically flooded with caffeine and trace levels of nicotine. They also report that the rivers carried up to 15 grams (g) per day of cocaine and 195 g/day of benzoylecgonine, one of its metabolites. And although the team found two amphetamine-like drugs, ecstasy (MDMA: 3,4-methylenedioxy-N-