Waste water contains a treasure trove of data on our health, well-being and inequality, and can be used to head off epidemics, track pandemics and even spot new designer drugs before their effects show up in the population. But how much information are we willing to flush down the toilet?
Health 16 August 2022
The countless chemicals and pathogens that you flush away end up in your nearest sewage treatment plant
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WHAT’S the largest source of mass moving in and out of a city every day? You think, if it’s a port city, it must be boats – or, you know, maybe if it’s a landlocked city, it’s trains or trucks or cars or planes. No, it’s water. It’s water. There’s so much more water moving in and out of a city any day than there is any kind of cargo. It’s basically pure water coming in. And then the water that leaves has some traces of almost every human activity that’s going on in the city.”
Once Eric Alm is in full flow, it is hard to stop him. But it isn’t hard to understand his enthusiasm. Alm, a biological engineer at the Massachusetts Institute of Technology, is one of a growing band of researchers turning their attention to the fluid coursing through our sewers. This waste water, as it is known, contains the whispered biochemical confessions of millions of people, and by listening to them, scientists can paint surprisingly detailed pictures of our health, wealth and environment, head off epidemics, track pandemics and even spot new “designer” drugs before their effects show up in the population.
Water treatment plant
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The field, called waste water-based epidemiology, not only has the potential to revolutionise public health but also transform our view of sewage from disgusting waste to …