Our pharmaceuticals and personal care products are turning up in the environment and in animals.  And they are showing up close to home.

St. Olaf chemistry professor Paul Jackson has been researching the presence of these substances in the Cannon River for three years.  Each summer, he and his undergraduate researchers (formerly Kyle Halvorson ’03, Justin Seningen ’03, and Elizabeth Thompson ’01, and currently Kirsten Rittenbach ‘05) strap on their hip waders, slog into the Cannon River, and sample for caffeine.

Without human consumption, caffeine would not be found in Minnesota’s waters.  Some tropical plants produce the chemical, but, as we all know, Minnesota is far from tropical.  Because caffeine is “exotic”, Jackson and his researchers use it as an indicator of human chemical influence.  Where caffeine shows up, other chemicals follow.

Pharmaceutical chemicals and personal care products –-steroids, hormones, anti-depressants, ibuprofen, painkillers, birth control drugs, antibiotics, and others –-are turning up in rivers across the United States.  Jackson has not studied all of them yet, but he recognizes the unique prospect the chemicals’ presence and persistence provides.

He and other environmental researchers are interested in whether these chemicals are present at levels high enough to alter species’ behavior and change ecosystem function. Most studies on the effects of pharmaceuticals are based on short-term, high-dose experiments.  But the presence of these chemicals in aquatic environments allows for studies of long-term, low-level exposure.  Of particular interest are hormones and steroids, like those found in antidepressants and birth control drugs.  Hormones and steroids switch human body processes on and off, and they might affect fish, birds, and other aquatic species in similar ways.

Fluoxetine, the active ingredient in Prozac, is one example.  Fluoxetine blocks nerves from gobbling up serotonin –-a neurotransmitter known to elevate mood and increase relaxation –-from the synapses between communicating neurons.  In lab studies, fish behaved less aggressively when injected with fluoxetine.  Whether the fluoxetine fish encounter through their gills or food in the Cannon River has similar effects remains to be seen. 

How do chemicals like fluoxetine enter our rivers?  The answer is simple enough.  We swallow pills, scrub our hands, drink cough medicine, and shampoo our hair.  Whatever chemicals are not metabolized or used up in the body spiral down our drains and eventually end up in our lakes and rivers.

Before these chemicals reach rivers and other bodies of water, they visit wastewater treatment facilities.  Treatment facilities, including Northfield’s, are not designed to filter specific chemicals.  They rely on microbes to munch up and decompose organic matter, to control bacterial growth, and to limit nutrients like carbon, nitrogen, and phosphorus.  So when treated water dumps back into the Cannon, the pharmaceutical and personal care chemicals come along for the ride.

The makeup, amounts, and effects of these chemicals in the Cannon River and other aquatic environments remain largely unknown.  Jackson has been interviewing local pharmacies, compiling lists of popular prescription and nonprescription drugs, and consulting previous studies done by the Environmental Protection Agency.  Come summer, he and his researchers will again strap on their waders and go looking for answers.