Clinical Pearls: Green supply chains in hospital pharmacy

April 23, 2024
By Huy Pham
This article is part of a series appearing in Interactions, our biweekly newsletter, written and researched by CSHP's students. We've created this series as a valuable learning activity for pharmacy students undertaking rotations at CSHP. Crafting these pieces not only helps students gain in-depth knowledge of specific conditions, treatments, and resources, it also helps them hone their skills in research, critical appraisal, evaluation, synthesis, and writing – all of which will serve them well in clinical practice. The Professional Practice Team works with the students to select hot topics that are of interest and utility to both the students and to you, the reader. We hope you enjoy this piece by one of our future colleagues! Let us know what you think: If you would like to provide any comments or constructive feedback for our students, please email us at


The Canadian drug supply chain can be conceptualized as having four phases: drug approval, manufacturing, procurement/distribution, and front-line delivery. The drug approval phase concerns the process of development of drugs by pharmaceutical companies and reviews of efficacy, safety, and quality performed by Health Canada to determine whether a drug product is approved for use in Canada. The manufacturing phase pertains to the mass production of pharmaceuticals and includes the process of acquiring the raw materials for the active pharmaceuticals, batch production, and surrounding Good Manufacturing Practices and quality control. The procurement/distribution phase of the drug supply chain describes the movement of pharmaceutical products from the manufacturers to the front-line users. Key players include the wholesalers and distributors, who are responsible for the warehousing and delivery of pharmaceutical products, and group purchasing organizations, who are the intermediaries for direct negotiation with manufacturers to secure cost savings. The front-line delivery phase refers to the end-user of the pharmaceutical products and includes hospitals, healthcare professionals, and patients.¹

Figure 1. Product flow of drugs to hospital pharmacies in Canada (adapted from Multi-Stakeholder Toolkit: A Toolkit for Improved Understanding and Transparency of Drug Shortage Response in Canada¹)

Environmental Impacts of Pharmaceuticals

There are many environmental impacts associated with the life cycle of pharmaceuticals and the drug supply chain, from the acquisition of raw materials to the disposal of drug products. These environmental impacts may broadly fall into these three categories: greenhouse gas emissions, pharmaceutical waste, and plastic waste.

Healthcare contributes 4.6% of Canada’s total greenhouse gas emissions and thus is a major contributor to climate change and its adverse impacts on health such as increased frequency of heat-related illness, exacerbations of asthma and chronic obstructive pulmonary disease due to exposure of wildfire smoke made more likely due to climate change, and worsening of mental disorders. The effects of climate change have both direct impacts on healthcare facilities and indirect impacts via effects on their supply chains, with the former contributing approximately 10% of total Canadian healthcare emissions and the latter the remaining 90% of the total emissions from healthcare in Canada. Pharmaceuticals, prescription and non-prescription drugs, contribute 25% of healthcare greenhouse gas emissions in Canada.²

Pharmaceuticals may appear in the natural environment through a variety of pathways. Pharmaceuticals excreted from the human body via urinary or fecal excretion pass through sewage treatment plants that are likely incapable of removing pharmaceuticals and its metabolites, effectively enabling their entry into natural waterways as part of the treated water and as part of the sewer sludge. Pharmaceuticals may also find entry into waterways when unused medications are improperly disposed. In addition, medications that are improperly disposed in solid waste may end up in landfills, where pharmaceutical residue can leach into the environment (soil, groundwater). Finally, the incineration of unused medications has the potential to release pollutants into the atmosphere.3

The presence of pharmaceuticals in the environment has numerous ecological impacts. Pharmaceuticals bioaccumulate up the food chain/web as predators consume organisms that are exposed to these pharmaceuticals. Humans may also be at risk through the consumption of organisms who have bioaccumulated pharmaceuticalse.4-6 Several studies have detected active pharmaceutical ingredients at concentrations that are known to cause acute and chronic toxicitiese.For instance, perch that were exposed to oxazepam in effluent-influenced surface waters exhibited alterations to their behaviour such as increased boldness, reduced sociality and increased feeding ratese.8,9 Another example includes vultures in South Asia who developed renal failure and gout due to exposure to diclofenac, causing the population to decline.10 The population decline of vultures had downstream effects. As scavengers, the vultures fed on uneaten carcasses that serve as breeding grounds for pathogenic bacteria and infectious diseases such as anthrax, which can posed a public health threat as these carcasses were in close proximity to human habitation. In addition, the decline in vultures enabled the growth of opportunistic species like feral dogs and rats, who are reservoirs of rabies and other zoonotic diseases. This resulted in the increased spread of rabies to humans.11,12 The overall decline in vulture populations and subsequence growth in dog and rat populations imposed an annual cost of over $1 billion cost to India.13 There is also a concern of increased antimicrobial resistance due to pharmaceuticals in the environment. A study of pharmaceutical pollution in the world's rivers found that over a quarter of the sampling sites had concentrations of ≥1 active pharmaceutical ingredient that exceeded what is considered safe for aquatic organisms or raised concern for antimicrobial resistance, with low- to middle-income countries being more likely to have these contaminated sites.14 Currently, there are no studies that observed a direct, acute impact of pharmaceuticals in the environment on human health.15-18 However, the possibility of harm from human exposure to pharmaceuticals in the environment cannot be ruled out as there are uncertainties relating to the effects of long-term exposure to pharmaceuticals in the environment through drinking water or the effects of simultaneous or sequential exposure to subtherapeutic concentrations of pharmaceuticals in the environment.17,19

Plastic waste from healthcare is also an environmental issue, where approximately 30% of all hospital waste is plastic.20 87% of all plastics in Canada, including healthcare plastics, ends up in landfills and the natural environment.21 Furthermore, 47% of plastic waste is from packaging.21 Plastics in the environment can cause physical harm to organisms through strangulation, starvation due to neck entanglement, and gastrointestinal obstruction due to ingestion of plastic debris.22 There is also ecological harm from the environmental leaching of the additives. For example, phthalate esters, which are widely used as plasticizers, can easily leach out of plastic products (specifically polyvinyl chloride products), where they can disrupt the endocrine and reproductive functions of organisms.23-25 Bisphenol A, another commonly used plasticizer, can interfere with the development and reproduction of aquatic animals and mammals.23-25 Exposure to these chemicals is associated with an increased risk of metabolic abnormalities like diabetes, reproductive dysfunctions, and breast cancer in humans.26,27

How Hospitals and Hospital Pharmacies Help Address the Environmental Impact of Pharmaceuticals

As one of the end-users of pharmaceuticals, hospitals, hospital pharmacists, and hospital pharmacy technicians  can play a major role in making the Canadian drug supply chain to become more environmentally sustainable. There is also growing interest in sustainable practices in the realm of Canadian healthcare, particularly with the formation of Creating A Sustainable Canadian Health System In A Climate Crisis (CASCADES) Canada with the aim of supporting a transition towards environmentally sustainable and resilient healthcare systems and the establishment of the Canadian Association of Pharmacy for the Environment (CAPhE) with a mission to promote planetary health in the pharmacy profession. In addition, CSHP has made environmental sustainability, one of its’ key priorities and has formed a sustainability task force in collaboration with CAPhE that will develop recommendations on how CSHP can move forward to integrate sustainability into hospital practice through advocacy and partnerships, education, sharing of research and quality improvement initiatives, and policy and procedure development.

One area that can be addressed is what specific medications are supplied to and used at the hospital. This is primarily based on what is listed in the hospital formulary, which is developed and approved by the Medical Advisory Committee (MAC) and the Pharmacy and Therapeutics (P&T) Committee. A drug is approved for use in a hospital based on a myriad of factors such as clinical efficacy of the drug, the financial impact of the hospital budget, and cost-effectiveness relative to available therapeutic alternatives. For the purposes of transitioning towards more environmentally friendly healthcare, the environmental impact of the drug can be included in the formulary submission and may serve as a criteria for evaluating the addition of the drugs to the formulary. The extent at which the active pharmaceutical ingredient(s) persist in the environment prior to degradation, the extent of bioaccumulation, and the ecological toxicity in particular could be points of consideration for determining if a drug may be added to the formulary. These would require discussions with the drug manufacturers and Health Canada to regulate this type of information pertaining to impacts on environment be included in their initial submission for drug approval.

A related area is the choice of suppliers from which the hospitals obtain their medications. Ideally, medications are being supplied from manufacturers that are intent on implementing green practices in the drug manufacturing process such as a transition to 100% renewable energy sources and waste minimization. This would involve discussions with the group purchasing organization, who can aid with identifying and prioritizing manufacturers implementing sustainability initiatives. Cooperation with group purchasing organizations may also help influence manufacturers towards sustainable practices through the leverage of collective purchasing power.

Hospitals may also address the environmental impact of pharmaceuticals (and by extension, hospital practice) through the establishment of a sustainability committee. This would ideally involve representatives from a variety of departments including representatives who are hospital pharmacists and pharmacy technicians. Sustainability committees could aid in facilitating change towards more sustainable practices including the green procurement of pharmaceuticals. They could also engage with suppliers and advocate for green proposals such as reducing the use of single-use plastic packaging for their products.

Hospital pharmacies can reduce the environmental impact of their operations by adopting green inventory management practices. For instance, the bulk purchase of drugs used at large quantities could aid in reducing emissions from transportation and waste from packaging. On the other hand, the purchase of smaller vial sizes could minimize the amount of waste from unused liquid medications. Regular monitoring of drug inventory may aid in reducing the amount of expired medications due to overstocking. A unit-dose medication distribution system could aid in reducing medication wastage compared to a traditional or ward stock system, with the additional benefit of reducing the error rate. Increasing the frequency for batch compounding of sterile products can also reduce the amount of unnecessary waste.28,29 For instance, a pediatric pharmacy's switch from a 1-batch-per-day to a 3-batch-per-day schedule reduced pharmaceutical waste by 31.3% from 28.7% to 19.7% with additional annual cost savings of $183,380.28 The reuse of supplies can also be useful in reducing waste. For example, metered-dose inhalers that are previously used with a patient-specific spacer can be reprocessed and reused after proper disinfection of the MDI canister, cap, and actuator with 70% isopropyl alcohol. The disinfection process may be performed by pharmacy technicians. These inhalers would have to assess for their remaining doses either by checking the dose counter or weighing the inhaler.30-32 This initiative would require cooperation with infection control departments to minimize cross-contamination and transmission of infections.

Individual hospital pharmacists may also consider environmental impact as part of their clinical decision-making for their pharmacotherapy care plan. For example, pharmacists can promote the use of dry powder inhalers or soft mist inhalers over metered-dose inhalers for asthma and chronic obstructive pulmonary disorder given that, unlike meter-dose inhalers dry powder inhalers and soft mist inhalers lack the use of hydrofluorocarbons, which are potent greenhouse gases. As a result, these inhalers have a smaller carbon footprint than metered-dose inhalers.33-35 This would ideally involve assessment of patients to determine if these inhalers are clinically appropriate as well as a discussion of patient preferences. Hospital pharmacists, through medication reviews, may also identify unnecessary drug therapies that can be deprescribed, thereby removing the environmental impacts associated with the follow-up monitoring and refill visits post-discharge.


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