Imagine this sticker above your light switch: Powered by Prozac.

No, it’s not likely that your local power plant will be swapping coal for old Celebrex tablets anytime soon. But a little free energy is the happy byproduct of drug disposal by Milwaukee-based Capital Returns, a company that specializes in the management of old pharmaceutical stocks.

Drugs have shelf life, beyond which they cannot be sold. But old medications are more difficult to get rid of than you might think. Drugs which get sent to landfills will eventually leech their way into the groundwater. Flushing old stock — the method generally recommended to consumers — puts chemicals into our watershed even faster.

Drug-Filled Rivers

And that’s a problem. Ignored for years, pharmaceutical water pollution is finally getting the attention of U.S. and European scientists as unexpectedly high levels of antibiotics, heart medication, anticonvulsive drugs, and a host of other powerful medications are turning up in rivers and groundwater. Perhaps the most disturbing pollutants are endocrine disruptors: human estrogen from birth-control pills and the vast effluence of animal hormones produced by commercial livestock production.

The effects of these substances on wildlife — and the human food chain — are just now being studied. But they’re likely to reveal bewildering mutations similar to the dual-sexed smallmouth bass turning up in the Potomac River north of Washington, DC.

Most pharmaceutical pollution makes its way to our watershed through the release of treated sewage. But controlled industrial incineration prevents old drug stocks from adding to the problem, and is being harnessed by Capital Returns to produce surplus power.

A Prescription for Free Power

Every day, the company receives millions of expired pharmaceuticals from drug manufacturers, cataloging their receipt and routing them for hazardous disposal or to Covanta Energy, a company which specializes in converting waste into energy. Covanta currently operates thirty facilities in the United States, offering communities an alternative to landfill dumping in the disposal of such things as municipal solid waste and household trash. Their incinerators exceed EPA regulations for air purity.

And now, expired drugs. Capital Returns disposed of over 6.5 million pounds of pills in 2006 — producing enough energy to power about 220 homes for a year. That’s tons of coal or natural gas saved and fewer pollutants making their way into the water table.

Next Stop: Your Corner Drug Store

Capital Returns says it handles about a quarter of the industry’s disposal needs. But they don’t address expired drugs already in the hands of consumers. Washington State is among the first to set up pilot programs to test the viability of public drop-off centers. Emma Johnson, who works for the state’s Department of Ecology, says a five county area has been experimenting with pharmacy-based drug collection centers since last October. If successful, the effort will be expanded statewide.

Converting drugs to power is, admittedly, a footnote to emerging story of 21st century alternative power solutions. But it illustrates the larger strategy of closing the loop on consumer goods, keeping dangerous wastes out of the environment while converting them into something useful.