• Energy Research

Fulfilling the SDGs and reaching the climate neutrality target of the EU Green Deal will require a global effort, for which solar energy is indispensable. From 2030 the global number of decommissioned and thus waste solar panels will increase exponentially. This review article specifies the barriers and solutions to creating a closed loop system (CLS) in the crystalline silicon (c-Si) photovoltaics industry in Germany. The conclusions drawn are however relevant for all countries using solar panels, as they will face similar challenges. Specific recommendations are outlined based on identified challenges that will help ensure a CLS for c-Si solar panels. Regarding regulation it is recommended that recycling targets for solar panels should be adjusted so that they are not linked to weight, as this does not encourage the recovery of all materials. It is also crucial that the design of the solar panels is adjusted to ensure that repair, refurbishment and at a later stage recycling are possible. Since the economic feasibility is not given at a small scale it is suggested for companies to join larger recycling schemes. Collaboration and exchange along the supply and value chain is also identified as essential to ensure the development of solutions that will truly enable the creation of a CLS. Product as a service should also be explored by solar panel companies as this would encourage the production of panels that can be easily repaired and later recycled.

Fulfilling the SDGs and reaching the climate neutrality target of the EU Green Deal will require a global effort, for which solar energy is indispensable. From 2030 the global number of decommissioned and thus waste solar panels will increase exponentially. This review article specifies the barriers and solutions to creating a closed loop system (CLS) in the crystalline silicon (c-Si) photovoltaics industry in Germany. The conclusions drawn are however relevant for all countries using solar panels, as they will face similar challenges. Specific recommendations are outlined based on identified challenges that will help ensure a CLS for c-Si solar panels. Regarding regulation it is recommended that recycling targets for solar panels should be adjusted so that they are not linked to weight, as this does not encourage the recovery of all materials. It is also crucial that the design of the solar panels is adjusted to ensure that repair, refurbishment and at a later stage recycling are possible. Since the economic feasibility is not given at a small scale it is suggested for companies to join larger recycling schemes. Collaboration and exchange along the supply and value chain is also identified as essential to ensure the development of solutions that will truly enable the creation of a CLS. Product as a service should also be explored by solar panel companies as this would encourage the production of panels that can be easily repaired and later recycled.

The race for environmentally-safe pesticides and biocides has been showing solutions ranging from pest-pathologic microorganisms to safer botanical extracts that can be incorporated in several formulations. Often linked to high biological activities, fruit residues can be recovered from food processing factories to obtain complex extracts enriched with several bioactive chemicals. Mango (Mangifera indica) fruits are processed into food products in high volumes across the globe and generate a consistent residue that contains, among others, the xanthonoid mangiferin and the flavonoid hyperoside. Both compounds have been linked to several pharmacological and pesticidal activities, although not yet studied for algicidal applications, a current concern specially for antifouling and harmful algae blooms control products. The challenge lies, however, not only on the degree of activity of the natural compounds, but also on the processes necessary to separate, isolate and formulate the bioactive compounds in order to obtain an effective final product. The solvent choice plays an important part regarding the selectivity of the separation and isolation of the main bioactive compounds from the solid waste matrix. Ethanolic mixtures in water have been consolidated recently as a promising extraction medium for flavonoids and xanthonoids, although hindered by solubility limitations. In this paper, aqueous solutions of ionic liquids (ILs) were tested, screened and optimized using Box-Behnken design and Response Surface Methodology to obtain mangiferin and hyperoside-enriched extracts. Results showed a greater concentration of mangiferin and hyperoside with 1-octyl-3-methylimidazolium chloride ([C8MIm] Cl), when compared to choline acetate and ethanolic extracts using optimized parameters. In terms of sufficiency, solvent selection between ILs and ethanolic extraction media was discussed considering economic and environmental factors. Ethanol/water mango waste extracts were then studied for their activity against Raphidocelis subcapitata microalgae, which showed a higher growth inhibition in comparison to standard solutions of mangiferin and hyperoside, either individually and in a 1:1 mixture. A EC50 value was found in relative low concentrations of mangiferin and hyperoside (0.015 mg L−1) detected in the extract, showcasing a promising approach to the direct use of residuary plant extracts in biocidal formulations.

The race for environmentally-safe pesticides and biocides has been showing solutions ranging from pest-pathologic microorganisms to safer botanical extracts that can be incorporated in several formulations. Often linked to high biological activities, fruit residues can be recovered from food processing factories to obtain complex extracts enriched with several bioactive chemicals. Mango (Mangifera indica) fruits are processed into food products in high volumes across the globe and generate a consistent residue that contains, among others, the xanthonoid mangiferin and the flavonoid hyperoside. Both compounds have been linked to several pharmacological and pesticidal activities, although not yet studied for algicidal applications, a current concern specially for antifouling and harmful algae blooms control products. The challenge lies, however, not only on the degree of activity of the natural compounds, but also on the processes necessary to separate, isolate and formulate the bioactive compounds in order to obtain an effective final product. The solvent choice plays an important part regarding the selectivity of the separation and isolation of the main bioactive compounds from the solid waste matrix. Ethanolic mixtures in water have been consolidated recently as a promising extraction medium for flavonoids and xanthonoids, although hindered by solubility limitations. In this paper, aqueous solutions of ionic liquids (ILs) were tested, screened and optimized using Box-Behnken design and Response Surface Methodology to obtain mangiferin and hyperoside-enriched extracts. Results showed a greater concentration of mangiferin and hyperoside with 1-octyl-3-methylimidazolium chloride ([C8MIm] Cl), when compared to choline acetate and ethanolic extracts using optimized parameters. In terms of sufficiency, solvent selection between ILs and ethanolic extraction media was discussed considering economic and environmental factors. Ethanol/water mango waste extracts were then studied for their activity against Raphidocelis subcapitata microalgae, which showed a higher growth inhibition in comparison to standard solutions of mangiferin and hyperoside, either individually and in a 1:1 mixture. A EC50 value was found in relative low concentrations of mangiferin and hyperoside (0.015 mg L−1) detected in the extract, showcasing a promising approach to the direct use of residuary plant extracts in biocidal formulations.

Medicines are essential to human health but can also impact the aquatic and terrestrial environment after use by patients and release via excreta into wastewater. We highlight the need for a GREENER approach to identify and meet important environmental criteria, which will help reduce the impact of medicinal residues on the environment. These criteria include effect reduction by avoiding nontarget effects or undesirable moieties, exposure reduction via lower emissions or environmental (bio)degradability, no PBT (persistent, bioaccumulative, and toxic) substances, and risk mitigation. With all of these criteria, however, patient health is of primary importance as medicines are required to be safe and efficacious for treating diseases. We discuss the feasibility of including these criteria for green by design active pharmaceutical ingredients in the process of drug discovery and development and which tools or assays are needed to accomplish this. The integrated GREENER approach can be used to accelerate discussions about future innovations in drug discovery and development.

Medicines are essential to human health but can also impact the aquatic and terrestrial environment after use by patients and release via excreta into wastewater. We highlight the need for a GREENER approach to identify and meet important environmental criteria, which will help reduce the impact of medicinal residues on the environment. These criteria include effect reduction by avoiding nontarget effects or undesirable moieties, exposure reduction via lower emissions or environmental (bio)degradability, no PBT (persistent, bioaccumulative, and toxic) substances, and risk mitigation. With all of these criteria, however, patient health is of primary importance as medicines are required to be safe and efficacious for treating diseases. We discuss the feasibility of including these criteria for green by design active pharmaceutical ingredients in the process of drug discovery and development and which tools or assays are needed to accomplish this. The integrated GREENER approach can be used to accelerate discussions about future innovations in drug discovery and development.

Active pharmaceutical ingredients (APIs), their metabolites and transformation products (TPs) are found as pollutants in the environment. They can impact human and environmental health. To address this issue, an efficient, long-term prevention strategy could be the design of APIs that have less impact on the natural environment, i.e. the design of greener APIs, by the implementation of environmental parameters into the drug discovery and development process (also abbreviated R&D for ‘research and development’). Our study aimed to evaluate the feasibility of the design of greener APIs based on insights from drug design experts working in large, research-based pharmaceutical companies. The feasibility evaluation also identified needs and incentives for process modification. For this purpose, 30 R&D and environmental experts from seven globally active pharmaceutical companies were interviewed along a structured questionnaire. Main findings are that the interviewed experts saw manifold opportunities to include properties rendering APIs greener in different stages along the R&D process. This implementation would be favoured by the fact that the pharmaceutical R&D process is very flexible and relies on balancing multiple parameters. Furthermore, some API properties that reduce environmental risks were considered compatible with common desirable properties for application. Environmental properties should be considered early during R&D, i.e. when molecules are screened and optimized. It has been found that availability of suitable in silico models and in vitro assays is crucial for this environmental consideration. Their attributes, e.g. throughput and costs, determine at which process stage they can be successfully applied. An intensified exchange between R&D and environmental experts within and outside companies would push the industrial application of the benign by design approach for APIs forward. Collaboration across pharmaceutical companies, authorities, and academia is seen as highly promising in this respect. Financial, social, and regulatory incentives would support future design of greener APIs.

Active pharmaceutical ingredients (APIs), their metabolites and transformation products (TPs) are found as pollutants in the environment. They can impact human and environmental health. To address this issue, an efficient, long-term prevention strategy could be the design of APIs that have less impact on the natural environment, i.e. the design of greener APIs, by the implementation of environmental parameters into the drug discovery and development process (also abbreviated R&D for ‘research and development’). Our study aimed to evaluate the feasibility of the design of greener APIs based on insights from drug design experts working in large, research-based pharmaceutical companies. The feasibility evaluation also identified needs and incentives for process modification. For this purpose, 30 R&D and environmental experts from seven globally active pharmaceutical companies were interviewed along a structured questionnaire. Main findings are that the interviewed experts saw manifold opportunities to include properties rendering APIs greener in different stages along the R&D process. This implementation would be favoured by the fact that the pharmaceutical R&D process is very flexible and relies on balancing multiple parameters. Furthermore, some API properties that reduce environmental risks were considered compatible with common desirable properties for application. Environmental properties should be considered early during R&D, i.e. when molecules are screened and optimized. It has been found that availability of suitable in silico models and in vitro assays is crucial for this environmental consideration. Their attributes, e.g. throughput and costs, determine at which process stage they can be successfully applied. An intensified exchange between R&D and environmental experts within and outside companies would push the industrial application of the benign by design approach for APIs forward. Collaboration across pharmaceutical companies, authorities, and academia is seen as highly promising in this respect. Financial, social, and regulatory incentives would support future design of greener APIs.