posted on Jun, 17 2013 @ 06:14 AM
Well it looks like the poor fish are on Prozac and it is not doing them any good...
According to new unpublished research by scientists fish that swim in water which is tainted by antidepressant drugs become anxious, antisocial and
even homicidal in some cases. This new research has found that these pharmaceuticals which are frequently being found in US streams are able to alter
the fish genes which are responsible for building brains and controlling their behaviour...
The fish used in the study were fathead minnows. Scientists exposed the fish to differing doses of Fluoxetine (trade name Prozac), Effexor and
Tegretol. The first two being used to treat dperession and the latter being used for seizure disorders or bipolar disorder. They found that the Prozac
had a bizarre effect on male fathead minnows...
Male minnows exposed to a small dose of the drug in laboratories ignored females. They spent more time under a tile, so their reproduction
decreased and they took more time capturing prey, according to Rebecca Klaper, a professor of freshwater sciences who spoke about her findings at a
Society of Environmental Toxicology and Chemistry conference last fall. Klaper said the doses of Prozac added to the fishes’ water were “very low
concentrations,” 1 part per billion, which is found in some wastewater discharged into streams.
When the dose was increased, but still at levels found in some wastewater, females produced fewer eggs and males became aggressive, killing females in
some cases, Klaper said at the conference.
The drugs seem to cause these behavioral problems by scrambling how genes in the fish brains are expressed, or turned on and off. The minnows were
exposed when they were a couple of months old and still developing.
There appeared to be architectural changes to the young minnows’ brains, Klaper said at the toxicology conference. Growth of the axons, which are
long nerve fibers that transmit information to the body, was disrupted.
Fish downstream of wastewater treatment plants are more at risk of pharmaceutical exposure, experts say.
The new findings build on Klaper’s previous research, which tested minnows with the gene changes to see how well they avoided predators. They
swam longer distances and made more directional changes, which suggests that the drugs induced anxiety.
The drugs used in the study were among the most common in sewage: Prozac, Effexor and Tegretol. The researchers tested each drug alone and in
“At high doses we expect brain changes,” Klaper said. “But we saw the gene expression changes and then behavioral changes at doses that we
consider environmentally relevant.”
However, there is too little evidence to know whether pharmaceuticals are having any impacts on fish populations in the wild, said Bryan Brooks, an
environmental science professor at Baylor University who has extensively studied pharmaceuticals in streams and fish.
Fathead minnows exposed to low doses of antidepressant drugs became anxious, anti-social and aggressive.
Previous Research: ~
New, Unpublished Research: ~
It is also worth noting that the doses of Prozac and Effexor used in the study were about 50 times higher than those found in wastewater treatment
plants. However the antidepressant Tegretol comes into treatment plants and goes out at near constant levels. This means that the treatment technology
is having no affect on the drug..
This could spell disaster for many fish populations that live down stream of any wastewater treatment plants as this is where the prescription drugs
are showing up at consistently higher rates than in other water ways. If the fish in the streams and rivers are experiencing the same effect as those
in the study that may mean many of the fish population will decline quite significantly. Especially with the effects of the drugs on fish reproduction
and catching prey...