Active pharmaceutical ingredients (APIs), their metabolites and transformation products occur globally in the environment. They risk the environmental and human health. These alarming circumstances highlight the strong need for efficient measures, which is also reflected in the EU strategies on sustainable chemicals and to pharmaceuticals in the environment [1,2]. Design of APIs mineralizing in the environment according to the concept Benign by Design (BbD) is a promising approach to tackle this challenge [3]. However, its implementation into the industrial API discovery process has not been discussed yet. To stimulate such a discussion and to better understand the applicability and limitations of BbD the generic API discovery process is reviewed briefly [4] and the concept BbD presented [3,5] to provide a better understanding of the feasibility of BbD. Bringing both aspects together, we conclude that the optimization phase within the API discovery seems to be the most appropriate point to implement environmental considerations. At this early stage costs are low and potential impact of design and variations of structures on the outcome is high. We found that pharmacological parameters required for application are sometimes even in line with environmental biodegradability since the conditions in the human body and the environment differ [6]. However, impacts on biodegradability through optimization of API’s parameters such as toxicity and stability must be considered together with design rules for biodegradability.
Understanding the feasibility of BbD support pharmaceutical companies to be prepared for upcoming regulations, announced by above-mentioned EU-strategies. We found also that the successful implementation of BbD depends on the availability of suitable tools and methods as well as incentives for research within constructive collaboration of industry, academia and authorities. Furthermore, BbD is generally applicable to chemicals. In fact, since no pharmacological properties need to be considered, the design of benign chemicals should be even easier.

References:
1.European Commission. Chemicals Strategy for Sustainability Towards a Toxic-Free Environment, available at: https://ec.europa.eu/environment/pdf/chemicals/2020/10/Strategy.pdf.
2.European Commission, European Union Strategic Approach to Pharmaceuticals in the Environment, available at: https://ec.europa.eu/environment/water/water-dangersub/pdf/strategic_approach_pharmaceuticals_env.PDF.
3.K. Kümmerer, Sustainable Chemistry and Pharmacy, 2019, 12, 100136.
4.L. Summerton, H. F. Sneddon, L. C. Jones and J. H. Clark, eds., Green and Sustainable Medicinal Chemistry. The Royal Society of Chemistry, 2016.
5.T. Rastogi, C. Leder and K. Kümmerer, Chemosphere, 2014, 111, 493–499.
6.K. Kümmerer and M. Hempel, Green and Sustainable Pharmacy, Springer, 2010.