When similar chemicals meet different rules: Environmental standards in the licensing of medicinal and plant protection products in the EU and USA

This article presents a comparative analysis of environmental standards employed in the licensing of human medicinal products (HMPs), veterinary medicinal products (VMPs), and plant protection products (PPPs) across the European Union (EU) and United States of America (USA). Despite structural and functional similarities, these chemicals are regulated separately, resulting in divergent environmental (risk) assessment (E(R)A) procedures. Using a qualitative case study approach, this research examines domestic licensing procedures across four thematic areas: institutional context, E(R)A requirements, post-authorisation obligations, and the treatment of legacy and generic products. We frame our analysis through the lens of three policy design concepts - integration, participation, and stringency - revealing that PPPs are subject to the most stringent environmental standards, followed by VMPs, and HMPs subject to the least. EU regulations are generally more stringent than those in the USA, particularly regarding E(R)A data requirements, substitution obligations, and the practical weight of the E(R)A in influencing licensing decision making. Our study identifies regulatory gaps, especially in the treatment of legacy products, co-formulants and categorical exclusions. We thus propose five policy recommendations to enhance the stringency of environmental standards in the licensing of these products: legislative enshrinement of E(R)A data requirements for pharmaceuticals; reduction of E(R)A categorical exclusion eligibility; extension of substitution obligation to pharmaceuticals; periodic licence renewals for medicinal products involving re-evaluation of E(R)A data; and E(R)As covering complete product formulations, not only active substances. This research contributes a novel cross sectoral and cross-jurisdictional perspective on synthetic chemicals regulation and environmental governance.