Prozac ingredient in Great Lakes killing off microbes, including E. coli

Marilyn sez, "Scientists in Erie, Pennsylvania, have found that minute concentrations of fluoxetine, the active ingredient in Prozac, are killing off microbial populations in the Great Lakes."
Killing off bacteria might seem like a good thing. "Your immediate thought is, 'well, that's good, because they're not supposed to be there anyways," said Mercyhurst College microbiologist Steve Mauro, whose team found fluoxetine in low doses in water near Lake Erie's beaches. "But what about all the other bacteria that are supposed to be there and part of that ecosystem?"

Treating clean lake water with similar strength doses killed off E. coli and enterococcus bacteria, both of which can cause serious infections in humans.

The fluoxetine found in Lake Erie is at very low levels--about one nanogram per liter of water, Mauro said. "It doesn't appear to be at a level that would be harmful to humans," or invertebrates, for that matter, though Mauro suspects that fluoxetine combined with other chemicals could be having a cumulative effect on the lake's ecosystem.

Prozac Killing E. coli in the Great Lakes (Thanks, Marilyn!)

(Image: Prozac, a Creative Commons Attribution (2.0) image from arenamontanus's photostream)


    1. Exactly! The Prozac has been diluted to homeopathic levels. Therefore, it has the _opposite_ effect on the bacteria. They get sad, and die :(

  1. Is it killing of the cyanophora and related blue greens?
    If that’s the case its a major issue, and fairly scary. Reminds me of the Italian study tracking cocaine use in cities by presence of its metabolites in waste water. Good study for certain. Science, it works b@@ches.

    pardon spelling, grammar and general coherence, I’m about to get on a plane, and self medicating. also, consider the validity of using captcha as an anti drunken driving mechanism for cars.

  2. Hey, I get my drinking water from there. It sounds like it’s probably not a good idea to be polluting our water with such chemicals, but… I’m actually kind of mellow about it.

  3. Ahh.. this makes me wonder if some of its action might be attributable to flora interaction in the gut.. killing off some offending critter. As I age, I begin to feel so much of our health is a matter of the complex galaxy of little beasties floating around in us as much as our “own” organ activity. So if you had something that might contribute to your agitation, and prozac (while working in the brain) also interacted with your own flora…

  4. Don’t worry about it: the bacteria will figure out a way to survive. And they’ll be damn happy at the same time.

    1. Yes, that’s why drinking water is treated. Water that looks perfectly clean can still be contaminated.

      1. I dispute it can be called “clean”, then. Natural, unpolluted, whatever – but clean? No.

        1. If it was perfectly clean, then it wouldn’t be lake water. When they’re saying “clean” they probably mean that it isn’t contaminated from non-lake sources (e.g. human waste). I’m not an expert on lake ecology, but I’d imagine that the aforementioned bacteria are part of the natural ecosystem. Clean can be a relative term.

          1. But it isn’t “clean” even in that sense, since untreated sewage does go into Lake Erie, usually after heavy rains – the infrastructure can’t handle lots of rainwater and sewage, so they open the floodgates into Lake Erie.

        2. What do you define as “clean” then? It’s necessarily a relative term. Very pure water- deionized water- is bad for you except in small doses. It disrupts your osmotic balance. I’m told it also tastes terrible.

          1. I tasted deionized water – most university science labs have faucets that put out deionized water, for cleaning lab equipment and so on – knowing that you’re not supposed to, of course. It does taste peculiar :)

            On topic, though, the great lakes are so dirty that when discussing whether or not a specific sample of great lakes water is clean or dirty I’m guessing that scientists who study it have a very, very relative view of it. “Clean” great lakes water is never going to be something that you would want to drink, or even swim in, in many cases. It may just not be in a particularly polluted area.

            Now, if I’m honest, the water isn’t actually that bad that you would wholly avoid touching it. I grew up in Buffalo NY and swam in Lake Erie a few times every summer, and spent a lot of time on its shore as my grandmother has a cottage on the opposite bank in Canada. However, there is a huge, visible to the naked eye (and to the microscope) difference between great lakes water and water you may find in other, relatively clean freshwater lakes. The Great Lakes *aren’t* clean, and you *do* have to be careful.

          2. I swear that’s one of those “not supposed to do” things in the lab that everyone is tempted to do. Common-sensibly it’s totally harmless and yet it’s technically a double no-no because eating or drinking in there at all is capital-F Forbidden.

            I bet there’s no bigger cause of misbehavior in the lab than telling students something is forbidden when their intuition tells them it’s trivial.

    2. Clean lake water contains fish, too. If there weren’t any, you’d have to wonder what’s keeping them away, and how clean the lake really is.

    3. Do you think natural bodies of water are sterile? Bacteria can be found under miles of solid rock so finding them in a huge lake shouldn’t be a surprise. Dumping human sewage in the water isn’t a natural state though.

      Ingesting some bacteria (with a few exceptions), including small amounts of e coli, isn’t going to kill you.

    4. Very, very small amounts of e. coli can also exist in treated water. Usually not enough to be harmful. They found a sample near where I go to school, but after extensive testing found no other samples, so the water was safe.

      (would’ve sucked, whole water supply to university would’ve been contaminated)

  5. After growing up in Cleveland, and drinking (delicious) Lake Erie tap water most of my life, I wish those fluoxetine levels were much higher.

  6. If it keeps up, the microbes will develop an immunity to the stuff in a relatively short time.

    1. Sort of. Definitely microbes will develop immunity, but not necessarily all of them, or to the same degree, or at the same rate. The result is that fluoxetine will change the balance of microbial communities, and potentially influence the ecological roles they perform.

  7. So why doesn’t it act as an antibiotic in humans who have many thousands of times that concentration in their bodies?

    1. Anon #17:

      Prozac is most effective at killing gram-positive bacteria. A lot of the flora in your gut and tract are gram-negative (okay lot of wiggle room in this statement.) Also Prozac is more synergistic with antibiotics than it is an antibiotic itself. I would assume the water also has concentrations of antibiotics from various waste water sources as well and the prozac is helping it along.

      Science to back it up:

  8. I guess Prozac makes bacteria as uninterested in engaging in reproductive acts as it does humans.

  9. I understand the concern for damaging a natural ecosystem, but i wonder if this information can be used for good?

    I don’t have an understanding of current decontamination procedures and how costly / effiecient they are but it seems like this might be useful in areas where clean water isn’t readily available?

    Perhaps its too slow and other methods work better seems like there’s a silver lining in this somewhere.

  10. Eventually bacteria will not only develop a resistance to the chemical but they will feel unusually upbeat and have a positive outlook on life.

  11. This is consistent with what scientists have been documenting for years. It first started in the river beds because there is no filtration system able to handle Prozac (and many other drugs). There is an article on CNN dated from 2003, just google “prozac found in fish”

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