FormalPara Key Summary Points

Why carry out this study?

There is increasing pressure to prefer propellant-free inhaler devices over pressurized metered-dose inhalers due to environmental considerations.

Three life cycle assessments were conducted on the Easyhaler product portfolio in 2019, 2021, and 2023 to assess and monitor the environmental performance of the products over time.

What was learned from the study?

Average carbon footprint of the Easyhaler has decreased 11.2% between the 2019 and 2023 assessments. The reported emissions are in agreement with the lower limit of the carbon footprint range typically reported for dry powder inhalers and a decreasing trend shows that the sustainability actions deployed in the value chain are taking effect.

The results help to identify the product life cycle stages with the largest environmental impacts, and thereby to target actions to minimize the impacts. Regularly repeated assessments also help to identify if any burden shifting has taken place between environmental variables.

Introduction

The Intergovernmental Panel on Climate Change (IPCC) is a United Nations body that assesses the science related to climate change, its impacts, and options for mitigating and adapting to its effects. Its latest assessment report highlights the extent to which global warming can be limited to 1.5 °C depends on cumulative carbon emissions before time of reaching global net-zero greenhouse gas emissions and the level of greenhouse gas emission reductions during this decade [1]. The urgency for climate action is clear, and the IPCC report underscores the need for immediate, bold, and sustained actions to tackle the climate crisis. The World Health Organization (WHO) has estimated that increases in malnutrition, malaria, diarrhea, and heat stress due to climate change will cause 250,000 deaths per year between 2030 and 2050 [2].

The National Health Service has reported that inhalers contribute significantly to the environmental impact of healthcare, accounting for 13% of the treatment-related carbon footprint (CF) [3]. Inhalers are the cornerstone of pharmacological treatment of asthma and COPD. However, these patient groups are also among the more vulnerable to immediate effects of climate change and are at risk to worsening symptoms and increased exacerbation rates [4, 5]. These effects are driven, for example, by increased heat waves [6], reduced air quality [7], and longer pollen seasons and higher pollen concentrations [8].

There is increasing pressure to shift from pressurized metered-dose inhalers (pMDIs) to dry powder inhalers (DPIs) or soft mist inhalers (SMIs) due to the significant CF of pMDIs. To aerosolize the drug formulation, pMDIs contain hydrofluoroalkane propellants that have a high global warming potential and therefore greenhouse gas emissions from pMDIs are at least an order of magnitude higher when compared to DPIs. Emissions from DPIs in general are estimated to be 7.5–30 gCO2e per actuation, while emissions from pMDIs are estimated to be 100–400 gCO2e per actuation [9]. In a 2022 assessment report, Montreal Protocol Medical and Chemicals Technical Options Committee (MCTOC) concluded that global warming is by far the most important environmental impact measure of inhalers by both quality-adjusted life-years and time-integrated species loss [10].

The environmental impact of inhaler treatment can be significantly reduced by preferring propellant-free inhalers in the treatment of respiratory diseases. The majority of patients are able to use all inhaler types when trained properly, and therefore guidelines have not preferred a certain device type. Recently updated GINA recommends preferring environmentally friendly inhalers when clinically appropriate to do so [11]. In addition to actions of individual patients and health care providers, sustainability is a key part of achieving the emission-reduction goals in the health care sector.

Life cycle analysis (LCA) is a comprehensive method that considers the environmental impacts of a product or process throughout its entire life cycle, including raw material extraction, production, distribution, use, and disposal [12]. By analyzing life cycles of their products, companies can identify areas where they can reduce environmental impact and improve their sustainability. This helps businesses to make informed decisions, to prioritize sustainable initiatives, and to communicate their environmental impact to stakeholders. However, since the model behind the LCA calculations is tailored for each analysis and is based on different assumptions, the results are typically not comparable [13].

In this work, we report the results from three consecutive LCAs performed with identical analyses, making them comparable for the Easyhaler inhaler portfolio, and analyze the factors behind the decreasing trend in climate impact.

Methods

To assess the environmental impact of the Easyhaler portfolio, three separate LCAs were conducted in 2019, 2021, and 2023. The first LCA in 2019 included four out of six products in the portfolio while 2021 and 2023 LCAs included all six products. In addition, a cover which may be used with the Easyhaler product was assessed in 2023 [14, 15].

The LCAs in this study were conducted according to the ISO standards ISO 14040:2006 and 14,044:2006. ISO 14040:2006 provides guidelines and principles for conducting and reporting LCA studies. The standard establishes a framework for conducting LCA and includes requirements for the goal and scope definition, inventory analysis, impact assessment, and interpretation phases of the assessment. ISO 14044:2006 provides more detailed requirements and guidelines for the conduct of LCA studies, including requirements for data quality, sensitivity analysis, and reporting.

A flow chart of the LCA is provided in Fig. 1. The scope of the LCA was defined to be the life cycle of a single inhaler and the functional unit was defined to be one inhaler along with the patient information leaflet and all the packaging materials. The protective cover was assessed separately in 2023. The data extraction was divided into five phases. The raw materials phase involved the acquisition of all materials needed for the end product. It comprised raw materials for the active pharmaceutical ingredient (API) and carrier, materials for the inhaler components, materials for the protective cover, packaging, and patient leaflet, as well as the transportation of all these materials. The production phase includes the production of the API and carrier, production of the protective cover, the manufacture of the powder formulation, the production of inhaler components, the assembly of the final product, and packaging. The transportation phase involves the transportation of the finished product. The disposal phase includes the disposal and waste management of the product at the end of its life cycle.

Fig. 1
figure 1

Flow chart of the Easyhaler life cycle analysis

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Detailed data on material use, energy consumption, and waste disposal methods were collected both from Orion Corporation’s own manufacturing sites as well as from the external suppliers. Transportation emissions were estimated using a selection of the most commonly used shipping routes and transportation methods for each action. An independent third-party consultant (Carbon Footprint Ltd, Basingstoke, UK) was responsible for evaluating the collected data, building the LCA model, and performing the data analysis. The data accuracy was estimated to be from very good to excellent. Where exact data were not available, proxies were used according to consultants’ discretion. EcoInvent v3.6 (2019), EcoInvent v3.7.1 (2020), EcoInvent v3.8 (2021), EcoInvent v.3.9.1 (2022), Defra/Beis 2017, 2019, 2020 and 2022, WRAP 2008, and AIB 2021 databases were used to calculate emission factors for transportation, manufacturing, and materials. To control burden-shifting, the effects on fossil depletion, human toxicity, marine eutrophication, freshwater eutrophication, ionizing radiation, ozone depletion, water depletion, agricultural land use, and urban land use were assessed in addition to CF. In general, many different factors may affect the LCA results, such as the LCA model, LCA software, LCI datasets, life cycle impact assessment (LCIA) methods, and the underlying assumptions. As changes in these could cause variations in the results, these were kept the same and/or in line for all three LCAs, making them consistent and comparable with each other.

This study did not include human or animal subjects and did not contain experiments requiring review of an ethics committee.

Results

The carbon footprint of Easyhaler products decreased on average 11.2% during the study period 2019–2023. The results for carbon footprint of the Easyhaler portfolio in more detail and calculated emission reductions are presented in Table 1. No burden shifting was observed between any of the environmental variables.

Table 1 Carbon footprint and emission change between the assessments for Easyhaler product portfolio
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The largest absolute contributors to the decrease of CF were the manufacture of inhaler components, assembly of the final product, and raw materials for inhaler components. For example, CF related to assembly of the final product including inhaler assembly, formulation of API and carrier, and packaging decreased approximately 53% from 2021 to 2023 assessment.

The emissions associated with incineration did not include the carbon emissions saved through energy recovery, as it was out of the scope of the LCA, as per ISO guidelines. The CF of a protective cover was 65.94 gCO2e with raw materials and manufacture being responsible for the majority of emissions, accounting for 68.8 and 16.5%, respectively.

Discussion

Sustainable development is a concept that aims to balance economic growth, environmental protection, and social well-being in a way that meets the needs of the present without compromising the ability of future generations to meet their own needs [16]. The WHO advocates for a proactive approach towards environmental awareness in the healthcare sector, recognizing that environmental sustainability measures can yield benefits for patients, healthcare providers, the health workforce, and the core functions of health systems. Additionally, such measures can reduce environmental health risks, while also helping to decrease costs and enhance the resilience of health systems [17].

This is also applicable to inhaler treatment. For example, in the UK, propellants from pMDIs account for approximately 13% of National Health Services CF related to the delivery of care and the vast majority of these emissions could be avoided without compromising the treatment of the patients by prioritizing inhaled medication via DPIs [3]. Although DPIs are often considered more expensive than pMDIs, this perception can vary depending on the specific device selected as a replacement. Wilkinson et al. conducted a study on the health economics of inhaler switches using 2017 NHS prescription data from England [18]. Their analysis showed that for 10% of pMDIs replaced with the cheapest equivalent DPI, the annual drug costs would decrease by €9.4 million. However, if the 2017 DPI brand distribution was retained, the costs would increase by €14.5 million. The prescribing physicians in partnership with the patients can directly affect both environmental impact and cost of the treatment by thoughtful inhaler prescription. The phase-out of hydrofluorocarbon gases in non-medical uses is expected to result in a significant increase in pMDI costs after 2025 [19].

Making changes to approved pharmaceutical products requires significant regulatory efforts, making it challenging to achieve rapid improvements in the environmental sustainability of medicines [20]. However, it is still possible to reduce the environmental impact of pharmaceuticals by focusing on the manufacturing processes, distribution, and disposal. LCA results may help to recognize the stages with the largest environmental impacts in the product life cycle, thereby enabling targeted actions to reduce the impacts. The pharmaceutical industry can adopt sustainable manufacturing practices that reduce the use of energy, water, and hazardous chemicals, and develop more environmentally friendly packaging and transportation options. Additionally, improving the disposal of unused drugs and reducing the number of pharmaceuticals that end up in waterways can significantly reduce the environmental impact of the industry [21]. A large portion of emission may be associated with actions of third-party suppliers, which highlights the importance of sustainability programs through the whole value chain and development of more environmentally friendly practices in partnership with the suppliers [22].

The largest decrease of emissions in the Easyhaler life cycle was observed in the manufacturing stage, and the decrease is in line with the global decarbonization of electricity grids. During the monitoring period, multiple energy-saving programs were conducted group-wide. For example, new local heat pump plants replacing purchased district heating were installed, ventilation and lighting was optimized, and sourcing of electricity was shifted to renewable and carbon-free sources. The CF of Easyhaler products agree with the general estimate by MCTOC for multidose DPI relievers, but for anti-inflammatory products, the CF of Easyhaler is 2–4 fold lower [10]. The CF of the protective cover was found to be one-tenth compared to the emissions from the product itself. The environmental effects of the cover are further mitigated by the fact that it can be reused.

Conclusions

The CF of Easyhaler products is in agreement with the lower end of the CF range previously reported for dry powder inhalers. The results show that the climate impact of pharmaceutical products can be reduced without making changes to the product itself. The manufacturing phase of the life cycle offers multiple possibilities for climate action such as increasing energy efficiency and preferring carbon-free and renewable energy. Although distribution represented only a small fraction of emissions for Easyhalers, it might offer meaningful and immediately executable possibilities for climate action. In addition, effective waste management and responsible raw material sourcing are crucial for reduction the environmental impact of pharmaceuticals in a broader context.