Where the drugs you take ultimately go
Dear readers,
After some time away in Spain I’m back. The news cycle has been overflowing with geopolitical conflict and economic standoff. You don’t need me to talk about any of that. And indeed though I have strong opinions, they may not be informed or qualified ones. I am, after all, trained as a scientist.
In this newsletter, I often write about big forces shaping our world- AI, climate change, and how science shapes society (and vice versa). But I find myself returning to stories where health and our environment collide because the information is urgent and actionable.
We need to talk about antibiotics in our rivers. I talk about superbugs a lot because of the urgency of the problem and because awareness still isn’t where it needs to be. And the science keeps flashing warning signs. My latest Hindustan Times column looks at a major new study on antibiotics in global waterways, with troubling data.
The antibiotics we take don't just treat us. They enter rivers. And they help breed superbugs.
You take an antibiotic. You feel better and move on. But the drug doesn’t vanish. It’s excreted and flows into the environment, often through untreated or poorly treated sewage.
A new study models that over 8,500 tonnes of human-used antibiotics enter rivers each year. And this staggering number doesn’t even include antibiotics from pharmaceutical factories, farms, or aquaculture.
Researchers tracked how the 40 most-used antibiotics moved through wastewater and surface waters. Even with sewage treatment, large amounts escaped. During dry months, residues concentrated to harmful levels across six million kilometers of rivers worldwide.
India is among the worst affected. About 87 percent of rivers exceed safe antibiotic levels, equating to 677,000 kilometers of waterways. Many cities don’t treat all sewage, and treatment plants rarely remove drug residues completely.
Common antibiotics like amoxicillin, cefixime, and ceftriaxone are found widely. Even low levels of antibiotics in rivers create selective pressure. Susceptible bacteria die. Resistant ones survive and pass on resistance genes.
The study estimates that 750 million people live within 10 kilometers of the most contaminated rivers. In India, that includes 315 million. Drinking just two liters a day from some rivers is enough to exceed safe exposure levels.
Even low doses can alter gut microbes and increase the risk of resistance. I have talked about this many times. Some Indian and Pakistani rivers contain over ten different antibiotics above safe limits. And this is just from human use. Antibiotics are widely used in agriculture.
In When the Drugs Don’t Work, I described how resistance often begins in the environment. Superbugs have already been found in rivers, drains, and public taps in Indian cities. The link between environmental contamination and resistance keeps getting clearer.
This is part of the reason I’m co-organizing in an upcoming meeting on antimicrobial resistance and superbugs (as part of my actual day-job). It’s the first scientific meeting of my organization in India, and it will bring together researchers working at the intersections of people, animals, and ecosystems.
All is certainly not lost, but more needs to be done and now to prevent superbugs from severely impacting our quality of life and health.
Stay well,
Anirban