Article | November 22, 2013

Sick Work! Sewage Exposure Stats And Solutions


By Kevin Westerling,


Everyone knows that sewer work is a “dirty job,” but there are factors — and real-life stories — that suggest the incidence and risk of sickness are rising.

Bedpan contents from quarantined hospital patients, radioactive chemicals, industrial chemicals, human blood from morgues, animal blood from labs — it all ends up in the sewer. Then, of course, there’s the usual: anything and everything that goes down the toilet or drainpipe. Sewer workers are a hardy breed, and they know full well that they’re dealing with some pretty gross … um, stuff. It may be an unwelcome surprise, however, to learn that the “stuff” they encounter is becoming increasingly pathogenic, and that the job is getting ever more dangerous.

Viruses Trending Up
There are approximately 3,000 viruses recognized in nature, but that merely scratches the surface of what exists. As scientists continually seek to identify more, they often visit the sewers, which are both a destination and a breeding ground for viruses. Many viruses are brought in by human and animal feces and urine, plant material, and the insects and rodents that make the sewers their home, but then they proliferate. The viral count expands when the host viruses infect the bacteria, rotifers, amoeba, and fungi that readily (and rapidly) grow in raw sewage. The longer sewage sits, the more viruses are created. Consider that a single bacterium will split, under proper conditions, every 20 minutes; the exponential growth rate amounts to 69 billion in a matter of 12 hours. With today’s water conservation efforts creating less flow and longer retention times — think low-flow toilets and urban sprawl — sewers are virtual petri dishes for new bacteria and viruses.

Image credit: "Faxing Hell," © 2012 Henry_Spencer, used under an Attribution-ShareAlike 2.0 Generic license: