Water in the Tennessee River isn’t going to give you the wake-up jolt that a cup of coffee does.
But it has enough caffeine to do that — and more — for the tiny wildlife living in and around the Tennessee River, according to researchers who found the presence of caffeine and a number of other drugs in the local water supply.
Caffeine exists in a high-enough concentration to force-feed a typical baby mayfly the equivalent of 26.6 cups of coffee a day, according to Sean Richards, associate professor of biological and environmental sciences at the University of Tennessee at Chattanooga. Caffeine was found in more than 93 percent of about 160 test samples of river water.
Meanwhile, Dr. Richards said, that mayfly also is ingesting a cocktail of at least 12 other common drugs, including several antibiotics, antidepressants and substances designed to lower human cholesterol levels. While the amount of drugs in the water is tiny by human standards, they one day may have a serious impact on the environment — and on humans, as well, he said.
Staff Photo by Meghan Brown The Tennessee River flows downstream from Nickajack Lake near South Pittsburg, Tenn., on Thursday. Many Tennessee towns in the river's watershed are looking to the river to solve their water shortages due to drought.
“Everyone’s worried about pesticides in the water, but the amount of pharmaceuticals that get dumped in the water via just taking them is going to equal or exceed that of pesticides,” Dr. Richards said. “You have to wonder what it’s doing to the ecosystem. If we’re upsetting the balance in any way, it can’t be perceived as a good thing.”
After taking drugs, people excrete the excess through urine, sweat and other body waste.
The issue of drugs in the water supply has surfaced in national media reports and congressional hearings in recent years. But Dr. Richards’ study, conducted with UTC associate chemistry professor Steven Symes, marks the first time Chattanooga’s water has been brought into the discussion.
The data about pharmaceutical concentrations in general are still few and far between, according to Dr. Symes. Researchers across the country have been able to study the issue for only the past decade as technology improved enough to measure the quantities of the drugs, which are recorded in parts per trillion, he said.
A landmark study published by the U.S. Geological Survey in 2002 and an Associated Press investigation last March delved into the issue, Dr. Symes said, but neither included any studies in Tennessee — despite the fact that historically, the Volunteer State has had one of the highest rates of prescription drug use in the country.
“We noticed a lack of data in the Tennessee River Valley,” he said. “We folded that with the fact that we know we’re very unhealthy, and we take lots of drugs.”
The team received a $251,720 grant from the National Science Foundation that allowed it to purchase the equipment needed to spend 21/2 years analyzing river water samples from Knoxville to Chattanooga, including the spot where the Moccasin Bend Wastewater Treatment Plant redeposits water into the river.
The scientists said they have yet to make the leap from testing river water to testing tap water that area residents might drink. But studies from other areas showing drugs in drinking water, combined with the testing on the supply from which Chattanooga’s drinking water is drawn, are troubling because they could prove a barometer for what’s to come in the human realm, Dr. Richards said.
“If you’re taking all these drugs at once, in really low concentrations, for your entire life, does that sound like a good thing? I don’t think so,” he said.
MORE STUDIES NEEDED
So far, the drugs have been detected here in minuscule proportions, the same as in other areas of the country, Dr. Richards said.
As in other studies, the pharmaceuticals were measured in parts per trillion in the local study, he said. One part per trillion would be the equivalent of one Tylenol tablet dissolved in 325 million liters — that’s 11 times the amount of water in the Georgia Aquarium, the largest aquarium in the world, he said.
Craig Mullinax, who lives in Ooltewah and manages the water division of Cleveland Utilities for the Cleveland, Tenn., confirmed that so far, there is no evidence that these diluted amounts are unsafe for human consumption.
“All those things are at such small levels that right now, the science needs to get better to determine whether they should, or could, be tested more,” Mr. Mullinax said. “The water is good. It’s safe, and it’s chlorinated. I drink it every day, and my family drinks it.”
But Drs. Richards and Symes say they remain concerned because the U.S. Environmental Protection Agency has yet to rule on the issue. Local and state agencies that regulate water quality here aren’t going to act until that happens, according to Meg Lockhart, spokeswoman for the Tennessee Department of Environment and Conservation.
“The U.S. Environmental Protection Agency has not yet set drinking water standards for (pharmaceuticals) at this time, and utilities are not required to test for them,” she said in a written statement.
But the EPA isn’t ready to take action until scientists are sure about the potential dangers involved, said Suzanne Rudzinski, deputy director for science and technology in the agency’s Office of Water.
“We believe the water supply is safe,” Ms. Rudzinski said, “but we remain concerned ... . We want to figure out what’s going on, and then if it’s appropriate, take action.”
The issue remains a priority for the agency, which is collecting information from health care facilities about how they are disposing of drugs and trying to get the word to the public about proper disposal procedures at home to avoid unnecessary dumping, she said.
That would reduce — but not eliminate — the problem, which persists because drugs are excreted naturally into the sewer system through toilets, sinks and showers, according to Christian Daughton, a research scientist with the EPA’s Office of Research and Development.
Scientists at UTC recently published results of a study in which they tested water from the Tennessee River, looking for 14 of the most-common active ingredients in pharmaceuticals. After testing at 20 sampling points in the river from Knoxville to Chattanooga over a two-year period, they found 13 of the 14 on their list. The concentrations they found fell into the ranges below, measured in parts per trillion:
Sulfamethoxazole (in the antibiotic Septra): 3.01-33.0
Carbamazepine (in the antiepileptics Tegretol, Carbatrol): 2.89-23.1
Trimethoprim (in the antibiotic Septra): 2.32-63.3
Acetaminophen (in the pain reliever Tylenol): 2.15-12.3
Diltiazem (in the antihypertensive Cardizem): 1.31-9.70
Ciprofloxacin (in the antibiotic Cipro): 4.74-54.2
Levofloxacin (in the antibiotic Levaquin): 6.15-59.3
Atorvastatin (in the cholesterol-reducer Lipitor): 2.70-101.3
Sertraline (in the antidepressant Zoloft): 2.43-12.4
Lovastatin (in the cholesterol-reducer Mevacor): 10.6-102.9
Fluoxetine (in the antidepressant Prozac): 3.91-10.1
Norfluoxetine (metabolic enhancer): 2.88 (median)
Ranitidine (in the histamine blocker Zantac): not detected
Total pharmaceuticals: 3.72-207.8
“Many drugs aren’t altered much by the body,” Dr. Daughton explained. “They circulate, do their thing and are excreted. You will have some that will survive the entire gauntlet of processes from the time you ingest a chemical to the time it comes out the other end of the sewage treatment plant.”
EPA researchers are looking more closely at which pharmaceuticals might be present in sewage sludge, according to Ms. Rudzinski.
They also are sampling fish tissues from 154 sites across the country for toxicology testing this summer and next, including a site on the Tennessee River about 12 miles downstream from Chattanooga, according to EPA spokeswoman Enesta Jones. Those study results will not be available until late 2010 or early 2011, she said.
Theodore Henry, an assistant professor and researcher with the University of Tennessee in Knoxville’s Center for Environmental Biotechnology and Department of Forestry, Wildlife and Fishery, has observed hormonal changes in fish exposed to antidepressants.
“We found changes in seratonin levels in the brains of these fish,” he said in a phone interview from his current research post in England, “and we demonstrated that there might be consequences.”
Dr. Richards wonders whether further testing will show that aquatic animals react to medications similarly to humans.
“If you think about Prozac, it mellows people out for the most part, and gives them a state of well-being,” he said. “If you give that to a fish, then how well are they going to be able to avoid a predator?”
the global IMPACT
Dr. Richards plans to study the effects of various drugs on tiny crustaceans commonly known as water fleas.
The connectivity of such small animals to larger species living in and around the water — including humans — is undeniable, said Anna George, director of the Tennessee Aquarium’s Research Institute.
Dr. George monitors the health of the river by these species and by salamanders, which she calls “the canary in the coal mine.” So far there has been no major concern, she said, but researchers are monitoring them.
“People maybe don’t care about one little salamander, per se,” she said, “but if we start losing our salamanders, it’s not going to be long before the water isn’t safe enough to swim in or to drink or to fish in.”
The thought of drugs in the Tennessee River troubles Chattanooga resident Aaron Meyer.
“It is a concern, because you don’t want that in the water,” Mr. Meyer said. “I swim in it and canoe in it all the time.”