Pharmaceutical pollution is an issue of increasing concern; not only can the residue from pharmaceutical products harm ecosystems and the environment, but their presence in groundwater, drinking water, soil and more could contribute to the growing threat of antibiotic resistance worldwide.
A new report by Health Care Without Harm Europe has examined the ways that hospital wastewater contributes to the amount of pharmaceuticals found in the environment and explores the different methods that European hospitals are using to reduce the amount of pharmaceutical residue in their wastewater.
A pilot wastewater treatment plant based on biological processes
Clinique Saint-Pierre Ottignies (CSPO), Belgium
In 2019, CSPO partnered with engineering company John Cockerill Balteau to trial a pilot wastewater treatment technology designed to treat macro-pollution, pharmaceutical pollution, and pathogenic microorganisms and antibiotic-resistant bacteria in the hospital’s wastewater.
John Cockerill Balteau’s MEDIX technology is based on biological processes that help eliminate micropollutants in water; using the enzyme capacities of micro-organisms, a wide range of pharmaceutical residues can be biologically degraded and removed.
Once broken down, the microorganisms are separated from the treated water using membrane filtration, generating a sludge waste that must be incinerated off-site.
The process has been found to remove more than 95% of pharmaceutical residues in wastewater.
Peracetic acid to neutralise antibiotic-resistant bacteria
Aarhus University Hospital, Denmark
Aarhus University Hospital began investigating how peracetic acid could reduce the level of antibiotic-resistant bacteria in its untreated wastewater in 2019.
The hospital’s research focused on ciprofloxacin-resistant bacteria, as ciprofloxacin is one of the most commonly used antibiotics in hospitals and primary care and is therefore likely to be found at high levels in hospital wastewater.
The hospital aimed for the level of ciprofloxacin-resistant bacteria in its wastewater to reach the same level as in household wastewater after treatment with peracetic acid.
To assess peracetic acid’s neutralising effect on ciprofloxacin-resistant bacteria, it was injected directly into the hospital’s untreated wastewater. Tests found that peracetic acid at different concentrations could reach a reduction rate of between 98% and 99.9% of ciprofloxacin-resistant bacteria after ten minutes.
Urine bags to keep iodinated contrast media out of the water cycle
MERK’MAL Project, Germany
Iodinated contrast media (ICM), contrast agents used for X-ray medical imaging, are generally excreted into sewage systems via human urine within 24 hours of consumption. As ICM cannot be completely removed by wastewater treatment plants, the substances enter the water cycle and accumulate over time.
While ICMs are not considered toxicologically harmful, health risks cannot be ruled out entirely. For example, drinking water containing ICM could become cause for concern; the chlorination of water containing a high concentration of the contrast agent iopamidol can lead to the formation of toxic by-products.
The MERK’MAL Project was launched by the IWW Water Centre in 2017 to explore whether urine bags would be a cost-effective means of reducing ICM in water.
The project focused on an area around two hospitals and two radiology practises: St Marien-Hospital Mülheim an der Ruhr, Evangelisches Krankenhaus Mülheim, Radiologische Gemeinschaftspraxis Mülheim and Medizinisches Versorgungszentrum Mülheim an der Ruhr.
Researchers behind the project saw a significant reduction of ICM concentrations in the effluent of the local wastewater treatment plant. It was estimated that the use of urine bags could prevent the discharge of 270kg of ICM into the surrounding city’s water every year.
Thermal plasma to degrade pharmaceutical residues
Radboud University Medical Center (Radboudumc), The Netherlands
MEDUWA-Vecht(e) is a collaboration between 27 Dutch and German companies, universities, hospitals, and governmental and non-governmental organisations to develop solutions to reduce or prevent the contamination of water, soil and food by medicines and multi-resistant microorganisms.
Radboudumc joined the project in 2014 and partnered with Dutch company VitalFluid to explore whether plasma-driven water activation could effectively degrade pharmaceutical residues from hospital wastewater before it enters the sewage system.
Plasma-driven water activation is an advanced oxidation process that increases reactive oxygen and nitrogen species that dissolve in water and break down contaminants. Radboudumc researchers investigated the efficiency of thermal plasma in degrading 14 pharmaceutical compounds commonly found in the Vechte river, compared with a more conventional treatment technique.
In the study, all pharmaceutical compounds in the water were reduced or completely degraded by both 150W thermal plasma and UV/H2O2 treatment.
A testbed for best practices to reduce pharmaceutical pollution
Caithness General Hospital (CGH), United Kingdom
The One Health Breakthrough Partnership (OHBP) was a collaboration between NHS Highland, Scottish Water, the Scottish Environment Protection Agency, HIE, the James Hutton Institute and the Environmental Research Institute of the University of the Highlands and Islands, aiming for a non-toxic environment in the Scottish Highlands. One of the collaboration’s main focuses was the impact of pharmaceuticals in the water environment.
OHBP partners conducted research in CGH, a rural hospital, assessing the efficiency of the local wastewater treatment plant in removing eight pharmaceutical residues: diclofenac, ibuprofen, paracetamol, clarithromycin, trimethoprim, carbamazepine, fluoxetine and 17-Alpha-ethinylestradiol.
All of the compounds, except 17-Alpha-ethinylestradiol, were detected in the hospital’s wastewater and the local wastewater plant. The plant was found to have a varying capacity to remove pharmaceutical contaminants from water before it is released.
In response to the findings, NHS Highland developed an action plan to reduce pharmaceutical pollution, including: a medicine waste ‘amnesty’ scheme to prevent unused medicines from being flushed into water systems, raising awareness through educational tools and public messaging, substituting the most environmentally damaging drugs for less toxic ones, and testing an innovative wastewater treatment filter to remove pharmaceutical contaminants.
After being used as a testbed for the project to remove pharmaceuticals from the environment, CGH became the first hospital in the world to gain the Alliance of Water Stewardship Standard.