Anaesthesia – is it really pain free for the environment?

Asbestos was finally banned in the UK in 1999, 102 years after the first health related issues were detected. It was linked to mesothelioma as far back as the 1930s. In fact, if you’ve just recovered from your annual Christmas ‘Wizard of Oz’, you might be surprised to learn that the snow used in the 1939 film was pure asbestos, used because it was fire retardant. Despite the obvious health risks, it took decades for asbestos to be regulated and removed from use. As a result, we are still seeing asbestos-related disease deaths today, with over 5000 reported in 2021 [1].

Fast forward a century and we are in a similar position with the issue of pharmaceutical pollution of the environment. In Anaesthesia News last year Allen et al. asked “But what about the fish?”, introducing the topic of ecotoxicology and the provision of sustainable healthcare to anaesthetic practice [2]. The discharge of pharmaceuticals into the aquatic environment by wastewater treatment plants across the UK and globally has been well documented [3, 4]. Most wastewater treatment plants were not designed to remove the increasing variety of novel and often complex organic pollutants efficiently, and many medicines undergo limited degradation and/ or transformation during treatment [5, 6].

Science drives policy, but despite science, policy development and regulation can take more than a generation to have an impact. 

Reports of harm from pharmaceuticals in the environment have been around since the 1960s. Despite rapid advancement in research techniques and knowledge since the late 1990s, the fate of pharmaceuticals, their metabolites and transformation products once introduced into the aquatic environment remains relatively unclear and means that we still cannot definitively state an impact on human or environmental health. In addition much of the research is performed on individual compounds, and of course our rivers and oceans contain a cocktail of drugs that may be reacting with each other and other contaminants. They also bond onto microplastic particles, which can concentrate their effect and deliver a bigger dose when eaten by aquatic life.

The pharmaceuticals used in anaesthesia and across healthcare have a clear potential to harm the environment in terms of toxicity, persistence and bio-accumulation. Of specific interest to anaesthetists may be:

• Propofol is an environmental hazard because it does not degrade, has the potential for significant bioaccumulation and persistence, and is toxic to aquatic life [7]. 
• Lidocaine has a short half-life in the environment, but its regular use and constant excretion results in pseudo-persistence [8]. 
• Diclofenac is suspected of causing damage to the inner organs in rainbow trout [9], and has led to the near-extinction of vultures on the Indian subcontinent, caused by birds feeding on the carcasses of cattle treated with the drug [10]. 
• Pyridostigmine and neostigmine are potentially toxic to Daphnia magna at concentrations in the order of μ.l ^-1 [11]. 
• Ketamine has been widely detected in surface waters. It is absorbed by shallow water fish, and marked changes were seen in the bacterial community in aquatic sediment [12]. 
• Recent work examining the practice of anaesthesia has resulted in dramatic reductions in carbon emissions from anaesthetic gases as well as improvements in the solid waste stream; however the potential aquatic impacts remain relatively unexplored. Given the benefits that pharmaceuticals confer in anaesthesia, potential strategies to mitigate their environmental impact must be directed to prevent, reduce, and manage their use without compromising patient care.

During the pandemic we have repeatedly heard the phrase “We will be led by the science”. Science drives policy, but despite science, policy development and regulation can take more than a generation to have an impact. So what are we to do in the meantime to reduce risk for human and environmental health from our clinical practice? The current year-on-year increase in the use of medicines means that while we are trying our best to make our patients healthier, we are potentially making our planet sicker. The NHS across the UK has committed to net zero healthcare with respect to carbon emissions – but shouldn’t we also be committing to net zero pollution and net zero harm to biodiversity?

This is the vision of the One Health Breakthrough Partnership, a unique collaboration between Scottish Water, the Scottish Environment Protection Agency, the Environmental Research Institute of the University of the Highlands and Islands and NHS Highland [13]. Together, we have a vision for a Highlands where non-toxic and sustainable healthcare is delivered. We are working together, sharing skills, data and perspectives, to reduce the impact of pharmaceuticals in the environment and slow the rise of antimicrobial resistance. While the evidence grows we are working using a precautionary principle, taking a public health upstream approach and using this as an opportunity to improve healthcare while reducing the load of pharmaceuticals on the environment. We are taking a ‘realistic medicine’ approach to the use of medicines, asking the patient “What matters to you?” (it may not always be that they want a medicine), and educating the public on the environmental effects of medicines and how to dispose of medicines waste. We are also educating clinicians across all professions, and ‘greening’ our formulary to offer prescribers less toxic choices that work for patients and the environment.

Of course, in anaesthesia, the perfect future would be one where much of the need for anaesthetic agents and surgery was reduced secondary to improved health of our population. In the meantime, being aware of the potential for environmental harm from the medicines we use should help us balance the priorities of clinical effectiveness and patient need versus protecting and restoring nature as the foundation of health. What will you do in your own life and practice?

Professor Sharon Pfleger
Consultant in Pharmaceutical Public Health
NHS Highland 

Twitter: @SharonPfleger

References 

1. Health and Safety Executive. Asbestos-related disease statistics, Great Britain 2021, 2021. https://www.hse.gov.uk/statistics/causdis/asbestos-related-disease.pdf (accessed 29/11/2021). 
2. Allen C, Baxter I, Oyedele O, Childs J. But what about the fish? Ecotoxicology and anaesthesia. Anaesthesia News; Issue 404: 10-1. 
3. aus der Beek T, Weber F-A, Bergmann A, et al. Pharmaceuticals in the environment – global occurrences and perspectives. Environmental Toxicology and Chemistry 2016; 35: 823-35. 
4. Wilkinson J, Hooda PS, Barker J, Barton S, Swinden J. Occurrence, fate and transformation of emerging contaminants in water: an overarching review of the field. Environmental Pollution 2017; 231: 954-70. 
5. Niemi L, Taggart M, Boyd K, et al. Assessing hospital impact on pharmaceutical levels in a rural ‘source-to-sink’ water system. Science of the Total Environment 2020; 737: 139618. 
6. Verlicchi P, Al Aukidy M, Zambello E. Occurrence of pharmaceutical compounds in urban wastewater: removal, mass load and environmental risk after a secondary treatment – a review. Science of the Total Environment 2012; 429: 123-55. 
7. Mankes RF. Propofol wastage in anesthesia. Anesthesia and Analgesia 2012; 114: 1091-1092. 
8. Kostrubiak M, Vatovec CM, Dupigny-Giroux L-A, Rizzo DM, Paganelli WC, Tsai MH. Water pollution and environmental concerns in anesthesiology. Journal of Medical Systems 2020; 44: 1-7. 
9. Triebskorn R, Casper H, Scheil V, Schwaiger J. Ultrastructural effects of pharmaceuticals (carbamazepine, clofibric acid, metoprolol, diclofenac) in rainbow trout (Oncorhynchus mykiss) and common carp (Cyprinus carpio). Analytical and Bioanalytical Chemistry 2007; 387: 1405-16. 
10. Oaks JL, Gilbert M, Virani MZ, et al. Diclofenac residues as the cause of vulture population decline in Pakistan. Nature 2004; 427: 630-3. 
11. Rocha R, Gonçalves F, Marques C, Nunes B. Environmental effects of anticholinesterasic therapeutic drugs on a crustacean species, Daphnia magna. Environmental Science Pollution Research 2014; 21: 4418-29. 
12. Wang Z, Han S, Cai M, Du P, Zhang Z, Li X. Environmental behavior of methamphetamine and ketamine in aquatic ecosystem: degradation, bioaccumulation, distribution, and associated shift in toxicity and bacterial community. Water Research 2020; 174: 115585. 
13. One Health Breakthrough Partnership. Home, 2021. https://ohbp.org/ (accessed 29/11/2021).