Water & superbugThe water industry needs to join the fight against superbugs
The fight against antibiotic-resistant bacteria — so-called “superbugs” — is a huge challenge, one that the World Health Organization has described as a grave global problem. The problem of antibiotic resistance is being exacerbated worldwide by the pollution of waste water with leftover drugs, providing breeding grounds for resistant bacteria and their genes. The problem can persist for years, constantly refreshed by new discharges of both drugs and of resistant bacteria themselves, shed by people and animals. It is time for the health and water industries to strike a bargain. Health professionals need to be aware of the need for pharmaceuticals to be managed as organic and persistent pollutants. Tackling hot spots in “source control” such as hospitals and clinics could make significant inroads on the amount of waste drugs entering treatment plants. The water industry should ensure that treatment plants are operating under optimal conditions and that the older ones are either replaced or upgraded.
The fight against antibiotic-resistant bacteria — so-called “superbugs” — is a huge challenge, one that the World Health Organization has described as a grave global problem.
When superbugs hit the headlines it’s often because of hospital outbreaks, such as the outbreak of Vancomycin Resistant Enterococcus that infected babies in Melbourne in 2013. Yet the problem isn’t confined to hospitals — the wider environment can be important in the development and spread of these bugs, and people can be infected through food and water.
The problem of antibiotic resistance is being exacerbated worldwide by the pollution of waste water with leftover drugs, providing breeding grounds for resistant bacteria and their genes. The problem can persist for years, constantly refreshed by new discharges of both drugs and of resistant bacteria themselves, shed by people and animals.
Warning from history
The fact that penicillin was found in soldiers’ urine in the Second World War was, in hindsight, an early indication that antibiotics are present in waste water, and that drugs like this might go on to have an afterlife in streams, lakes and other waterways, clinging to sediment particles and upsetting the delicate bacterial balances in soils and aquatic ecosystems.
But no-one gave the issue much thought until chance intervened in 1992, when German scientists looking for herbicides in rivers, groundwater and lakes stumbled across a chemical they didn’t recognize — it turned out to be the cholesterol-lowering drug clofibrate, a cousin of the weed killer 2-4-D.
No end of pharmaceutical pollution has since been found in the world’s water — analgesics, antibiotics, lipid regulators, antiseptics, beta-blockers, contraceptive hormones, anticonvulsants and X-ray contrast agents. Detectable levels of clofibrate alone are now found throughout the North Sea.
We now know that partially degraded drugs and ointments can be converted back into their active form through chemical reactions once you’ve said goodbye to them in the loo or shower. Many biodegrade, but others can be very persistent in their new environmental home.
Water treatment plants are thus the last barrier to drug residues and other synthetic chemicals being set loose into soils and waterways (meanwhile, there is no barrier at all for freely administered livestock drugs such as the antibiotics sulphasalazine and oxytetracycline).
