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Comment by barrkel | Hacker News Reader

One would hope that antibiotic resistant bacteria would be outcompeted in sewage by other bacteria with more mundane selection pressures.

Alternatively, the sewage actually has residual antibiotics in it. A cursory Google indicates this may be the case. They ought to be removed from the sewage by treatment.

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> They ought to be removed from the sewage by treatment.

The bacteries were found in a sewage treatment plant.

Even if you assume that there's a practical way to get rid of the anitbiotics at the plant (enzymes, maybe?), the bugs and drugs were in the sewage all along up to that point, allowing AB resistance to develop in the pipes upstream.

There's more than just antibiotics in wastewater, google for studies relating to the feminization of fish due to the residual levels of anti depressants in wastewater. The processes used determine what gets removed from the water. Most facilities use aerobic breeding zones, forcing extremely high volumes of air into the water to allow from friendly microbes that actually end up doing most of the real work digesting the waste. Microbes don't eat everything, so expecting them to eat the all of the unwanted products in the sewage is not going to happen. To get everything, you would need first research to identify bugs that eat the particular thing your wanted disposed of, and then a new zone at treatment plants for that process. Its real easy to say yeah they should remove this, but when you get into the details to understand why its not happening you begin to see this is a massive undertaking.

Um, it isn't anti-depressants that are feminizing fish. That doesn't even make sense. It is synthetic estrogens, ie pee from women taking birth control pills. Also a few other things, bisphenol A, and certain types of natural and synthetic steroids that are byproducts of agricultural run-off and cattle farming.

http://www.sciencedaily.com/releases/2010/07/100729122332.ht...

Thank your for the correction, I always make at least one mistake before I've had coffee.

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