The water industry needs to join the fight against superbugs
Crucial treatment
Treatment plants’ ability to strip out waste drugs varies enormously according to age, level of expertise, and design standard. Even the best ones don’t remove all foreign chemicals. Advanced treatment processes are designed more for removing pathogens than for breaking down molecules, although chlorination and what’s known in the trade as “ozonation” do have some ability to change the chemistry of drug molecules (to exactly what is unclear).
As the use of recycled water increases, the quality of this water becomes more critical and good management of all sewer inputs by water companies becomes more important. Thus, pharmaceuticals are being identified as a potential risk in recycled water risk-management systems of utilities such as South East Water in Melbourne, Orange County Sanitation District in California, and Singapore’s NEWater scheme.
This is leading to an increased awareness of the waste contributions from domestic catchments and high-concentration point sources such as hospitals.
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. They can help the water treatment industry by being aware of what their activities are putting into the sewerage and waste disposal systems, in view of the limited extent to which these systems can deal with the large number of drugs that are stable. They should consider prescribing less toxic, less environmentally persistent, but equally effective drugs where possible, as well as trying to reduce overall drug use in the community.
Meanwhile, Australia should build on its reputation for innovation in water management by addressing this health issue. Tackling hot spots in “source control” such as hospitals and clinics could make significant inroads on the amount of waste drugs entering treatment plants. Treatment at source may be preferable to facing increased trade waste charges by utilities if they deem hospital wastewater inputs to be problematic. Water firms should discourage hospital staff from emptying half-empty syringes into wash basins (which is probably common despite being against protocols) should also be discouraged. Rubbish disposal systems that minimize medicines ending up in landfill are another must.
The water industry should ensure that treatment plants are operating under optimal conditions and that the older ones are either replaced or upgraded. Where appropriate, the industry could also help hospitals with in-house waste treatment, and suggest ways for householders to dispose of unwanted drugs — perhaps along the lines of Orange County’s No Drugs Down the Drain campaign.
The search for new antibiotics to beat superantibiotics goes on. The discovery of one of the very few new candidate antibiotics in the past thirty years, teixobactin, while encouraging, is no cause for complacency.
Peter Fisher is adjunct Professor, Global, Urban and Social Studies at RMIT University. Peter Collignon is Professor, infectious diseases and microbiology at Australian National University. This article was co-authored by David Smith, water quality manager for South East Water, Melbourne. This article is published courtesy of The Conversation (under Creative Commons-Attribution/No derivatives).
