That began to change in the 1930s. Following the success of early sulfa drugs, which demonstrated that chemically synthesised medicines could be produced reliably and at scale, the once small-scale apothecaries of the late 1800s and early 1900s – including big names like Merck, Eli Lilly, and Roche – increasingly became industrial manufacturers, operating at the intersection of chemistry, medicine, and expanding healthcare markets.

The shift towards industrialised pharma accelerated during the Second World War, when penicillin was produced at an unprecedented scale through collaboration between governments and industry in the US and UK. The breakthrough saved countless lives and redefined what medicine could do – and how quickly it could be made. However, it also cemented a manufacturing model built around speed, volume, and chemical intensity.

In the post-war decades, synthetic drug development surged. Antibiotics, hormones, and treatments for chronic disease moved rapidly from laboratory to factory floor as production sites rapidly emerged across countries in Europe and North America. The environmental impact was rarely discussed. As such, water use, solvent disposal, and emissions became embedded in the foundations of modern pharma, largely unseen.

Regulatory reform also gave rise to an increase in environmental awareness. By the late 1960s, scientific research was beginning to draw attention to industrial pollution, while the establishment of the US Environmental Protection Agency in 1970 marked a turning point in how manufacturing industries were governed. Pharmaceutical production, once largely self-policed, now sat within a broader regulatory environment shaped by air, water, and waste controls.

Meanwhile, the industry’s product footprint was expanding in new ways. Plastic blister packaging and child-resistant “push and turn” containers, introduced in the 60s to improve safety and adherence, quietly embedded plastic into pharma manufacturing and delivery systems. Sustainability, as a concept, remained nascent – but the foundations of today’s challenges were already forming.

Globally, the decade also marked conceptual change. The Brundtland Report, published by the UN in 1987, introduced the idea of sustainable development, framing economic growth, environmental protection, and human health as interdependent, rather than competing priorities. That same year, the Montreal Protocol demonstrated that international action could successfully regulate harmful industrial substances.

Climate entered the global agenda with the UN Kyoto Protocol in 1997, placing emissions-intensive industries under future pressure. Pharma largely sat outside the immediate spotlight, but, by the end of the decade, sustainability existed as a set of parallel conversations – access, ethics, environment – rather than a cohesive strategy.

Inside organisations, small but significant operational changes followed. Green chemistry programmes sought to reduce solvent use and waste, signalling that sustainability could live within R&D, rather than alongside it.

As climate science sharpened throughout the decade, sustainability ambitions became harder to separate from health outcomes. Reports from the WHO increasingly linked climate change to disease burden shifts, painting environmental responsibility as a public health concern, while corporate reporting grew more integrated, addressing emissions, access, and ethical conduct within the same narrative.

Attention also turned to the unintended afterlife of pharma products. Notably, research identifying drug residues in rivers and groundwater widened sustainability’s scope beyond factory gates, raising questions about lifecycle responsibility and ecological impact.

Momentum continued with the landmark 2015 Paris Agreement. While pharma companies were not immediate targets for the treaty’s national climate action plans, the implication was clear enough: emissions targets would not stop at headquarters. Supply chains would be next.

By the end of the decade, sustainability had become far more measurable – and considerably harder to sweep aside. The Access to Medicine Index began shaping investor perception, embedding access and governance within ESG evaluation. At the same time, antimicrobial resistance exposed a more uncomfortable truth: environmental practice and public health were not separate concerns. Moreover, the AMR Industry Alliance underscored how antibiotic manufacturing discharge could directly undermine the medicines themselves.

Lockdowns followed. Borders closed. Raw materials stalled. What had once been described as efficiency was suddenly exposed as risk. Against this backdrop, sustainability expanded in real time. It came to include continuity, redundancy, and the ability to deliver medicines under extreme conditions, rather than ideal ones.

That same year, expectations sharpened on the demand side. In 2020, the NHS became the world’s first health system to commit to reaching net-zero emissions, sending a clear signal to suppliers that environmental performance would increasingly shape procurement decisions. The Health and Care Act later reinforced that ambition, embedding emissions and environmental targets into decision-making across NHS trusts and integrated care boards. For pharmaceutical companies, sustainability was no longer confined to voluntary reporting. It was fast becoming a condition of market access.

It was against this backdrop that AstraZeneca launched its Ambition Zero Carbon strategy in early 2020. The commitment was explicit: eliminate emissions from global operations by 2025 and reach net zero across the value chain by 2045.

Unlike earlier pledges, the strategy prioritised direct emissions reduction over offsetting. Investment followed, spanning renewable energy, fleet electrification, and lower-impact drug design.

Crucially, the strategy linked environmental sustainability to patient health. AstraZeneca committed up to $1 billion not only to decarbonisation, but to the development of next-generation respiratory inhalers with near-zero global warming potential propellants. Product redesign now sat alongside manufacturing and logistics as a sustainability lever.

Their climate cost remained high. HFC-134a, used widely in inhalers such as GSK’s Ventolin, carries a global warming potential more than a thousand times greater than carbon dioxide.

By 2021, this legacy had become impossible to sidestep. GSK disclosed that Ventolin alone accounted for nearly half of its global carbon footprint – equivalent to millions of tonnes of CO2. Regulatory pressure intensified after an EU agreement to phase out HFC consumption by 2050, forcing companies to confront the environmental impact of long-established, clinically essential products.

Inhalers became a focal point. Not just because of their scale, but because they revealed something broader: sustainability was no longer simply about operational efficiency. It demanded redesign.

As company strategies sharpened, regulation moved closer behind. The EU’s Corporate Sustainability Reporting Directive marked a step change in the depth and consistency of non-financial reporting. Emissions, water use, waste, and supply-chain risk were no longer framed as aspirational. They were becoming mandatory.

Attention also shifted downstream. For most pharmaceutical companies, the majority of their environmental impact lay outside direct operations, embedded in supplier networks and contract manufacturing. Pressure mounted across the industry. Sustainability teams gained influence, and open letters and joint initiatives reinforced the message: sustainability was becoming structural.

The EU’s Corporate Sustainability Reporting Directive fundamentally changed the terms of engagement. For pharmaceutical companies operating in Europe, sustainability disclosure became mandatory, detailed, and auditable. Reporting expanded well beyond headline carbon targets to include water use, waste, biodiversity, and supply-chain exposure. ESG data moved out of communications and into finance, legal, and procurement. It stopped being narrative and started being operational.

Pressure intensified at the product level, too. Long-standing reliance on hydrofluorocarbon propellants in metered-dose inhalers faced renewed scrutiny as Europe accelerated plans to eliminate HFC use entirely by 2050. For companies such as GSK and AstraZeneca, whose inhalers serve tens of millions of patients worldwide, this placed sustainability in direct tension with legacy product design. Investment in next-generation, low global warming potential inhalers shifted from future ambition to near-term necessity.

Meanwhile, antimicrobial resistance continued to underline how environmental degradation and public health outcomes were entwined. Work by the AMR Industry Alliance on wastewater discharge standards reinforced a growing realisation that sustainability failures could directly undermine therapeutic effectiveness.

By the end of the year, the tone had changed. The space for ambiguous commitment narrowed, replaced by expectation, comparability, and exposure.

What began as scattered gestures of responsibility has solidified into something closer to accountability – shaped by regulation, finance, and lived experience as much as by corporate intent. The World Health Organization's Department of Regulation and Prequalification issued a call for action entitled "Greener pharmaceuticals' regulatory highway," underscoring the urgent need for innovative regulatory practices to reduce the environmental footprint of medical products while maintaining high standards of safety and efficacy. The ISO Net Zero Guidelines followed, enabling businesses to chart a course towards net zero and facilitate global accountability through accreditation and transparency mechanisms.

Regulatory frameworks are now translating ambition into obligation. Regulation continued to tighten around pollution and waste. Revisions to the EU Urban Wastewater Treatment Directive and new packaging rules introduced extended producer responsibility, shifting the cost of pharmaceutical micro-pollutants decisively onto manufacturers. What had once been treated as downstream impact now carried direct financial consequence – despite strong objection from many pharma companies.

The EU's Packaging and Packaging Waste Regulation adds further compliance burdens. While the pharmaceutical sector voices concerns about competitiveness and medicine availability, cleanroom technology providers should view this as a clear signal of market transformation.

Corporate response has moved beyond rhetoric. AstraZeneca and GSK have partnered with pharmaceutical suppliers to collectively procure renewable power in China, unlocking approximately 225GWh of renewable electricity annually for operations spanning research, development, and manufacturing.

Danish manufacturer Novo Nordisk launched 'Suppliers for Zero', a structured environmental sustainability programme targeting its entire value chain – recognition that more than 95% of the company's environmental impact stems from Scope 3 emissions occurring outside direct operations.

GSK and AstraZeneca are now vying to be the first to upgrade their popular inhalers, with GSK planning final trials to improve the gas propellant in its 55-year-old Ventolin inhaler. Success could cut the company's entire carbon footprint by more than 40%.

The question is no longer whether pharmaceutical companies should act sustainably, but whether they can afford not to.