I. Introduction to Terephthalic Acid in Pharma

In the fast-paced pharmaceutical industry, where innovation and efficiency drive success, sustainability is also increasingly a concern given the limited nature of natural resources (Swaminathan, 2024). The pharmaceutical industry, which has traditionally relied on fossil-based chemicals, is also looking at greener options to solve environmental issues. One such invention includes employing terephthalic acid, a chemical well recognized for its use in the production of polyethylene terephthalate (PET) plastics (Schwab, 2024), as a pharmaceutical intermediary (Johnson, 2025).  By getting terephthalic acid from recycled PET, the industry may cut waste and carbon emissions while still producing important pharmaceuticals like paracetamol. This article investigates the use of terephthalic acid in medicines, its origins in plastics, and its potential to redefine sustainable medication manufacture.

II. What is Terephthalic Acid and Its Role in Pharmaceuticals?

Terephthalic acid is a white, crystalline powder that is typically made by oxidizing p-xylene, a petroleum product. It is frequently used in the manufacturing of PET plastic bottles and packaging (Lapa, 2023).  Its chemical structure, which comprises two carboxyl groups on a benzene ring, makes it appropriate for a wide range of industrial applications, including medicine (Lundbeck, 2005).  Terephthalic acid is used as an intermediate in drug manufacturing, most notably in the formation of certain pharmaceuticals such as citalopram and escitalopram (Lundbeck, 2010), and more recently as a precursor for paracetamol (acetaminophen) using new biotechnological techniques (Johnson, 2025).

Unlike standard paracetamol production, which requires energy-intensive, fossil-based phenol (Prescott, 1996), a novel approach uses terephthalic acid generated from recycled PET plastics.  This approach uses genetically modified Escherichia coli to convert terephthalic acid into paracetamol by microbial fermentation, providing a sustainable alternative that meets worldwide environmental standards (Johnson, 2025).

III. Sources of Terephthalic Acid: From Plastics to Pharma

Terephthalic acid may be extracted from waste PET plastics, such as discarded water bottles, using chemical recycling techniques such as alkaline hydrolysis or glycolysis (Bohre, 2023).  These techniques degrade PET into its monomers, including terephthalic acid, which may be refined to pharmaceutical-grade levels.  Recycling PET not only eliminates plastic waste but also reduces dependency on petroleum-based feedstocks, therefore mitigating the pharmaceutical industry's considerable environmental impact.

For example, chemical recycling may produce high-purity terephthalic acid, with studies indicating recovery rates of up to 90% from PET trash (Benyathiar, 2022).  This circular strategy is sustainable by converting plastic trash into a useful resource for medication manufacture, minimizing landfill use, and cutting carbon emissions when compared to conventional synthesis techniques.

IV. Production Process: From Terephthalic Acid to Paracetamol

The revolutionary approach to generate paracetamol from terephthalic acid consists of three steps (Johnson, 2025):

1. PET Depolymerization: Terephthalic acid is produced by collecting waste PET plastics and processing them using methods such as      alkaline hydrolysis.

2. Microbial Fermentation: Genetically engineered E. coli bacteria convert terephthalic acid into p-aminobenzoic      acid (PABA) through a Lossen rearrangement, a chemical reaction that rearranges molecular structures.

3. Paracetamol Synthesis: PABA is then converted into paracetamol also by genetically      modified E. coli, yielding up to      92% in under 24 hours at room temperature.

This biotechnology technique, created by academics at the University of Edinburgh, emits far less carbon than existing approaches, which rely on high-temperature chemical processes and produce emissions 55% greater than the automobile sector (Johnson, 2025).  The usage of recycled PET improves sustainability by lowering the demand for virgin resources.

V. Case Study: University of Edinburgh and AstraZeneca Collaboration

Background

AstraZeneca, a worldwide biopharmaceutical leader with operations in over 125 countries, collaborated with the University of Edinburgh and the Engineering and Physical Sciences Research Council (EPSRC) to promote sustainable pharmaceutical manufacture. The company supported the project with an iCASE studentship (Johnson, 2025).

Environmental Commitment

AstraZeneca's Ambition Zero Carbon initiative seeks to eliminate carbon emissions from its activities by 2025 and across its value chain by 2045 (AstraZeneca, 2020). The paracetamol project supports these objectives by utilizing biotechnology to cut emissions and reuse plastic waste. The process runs in ambient conditions, reducing energy consumption and complying with the EU's Green Deal and Circular Economy Action Plan (European, n.d.).

Social Impact

This AstraZeneca initiative promotes global health equity by sponsoring research to enhance the sustainability of paracetamol manufacturing. This project reduces the cost of Paracetamol, a popular pain reliever, by manufacturing it in a cost-effective, environmentally friendly manner, thereby contributing to the UN Sustainable Development Goals (SDGs) for good health, responsible consumption and production, industry, innovation, and infrastructure (UN, n.d.).

Results and Recognition

The Edinburgh-AstraZeneca experiment produced paracetamol with a 92% yield and much lower emissions than standard techniques.  This breakthrough has been acknowledged as a step toward decarbonizing pharmaceutical supply chains, with commendation from sustainability-focused magazines such as Sustainable Plastics and C&EN (Santos, 2025) (Thompson, 2025).

VI. Challenges in Implementing This Method

Despite its potential, various obstacles prevent the widespread use of terephthalic acid-based pharmaceutical production:

• PET Waste Quality: Variability in the composition of recycled PET might impair terephthalic acid purity, necessitating strict quality control (Umdagas, 2025).                                                                                                                                                                                                                                    

• Regulatory Constraints: Producing paracetamol from recycled PET trash would require a new FDA clearance for a generic via an Abbreviated New Drug Application (ANDA) to accommodate the new innovative biotech technique into the drug production process. (Wittayanukorn, 2020).

• Economic unknowns: It is not known if the manufacturing costs of paracetamol from plastic will be lower than traditional methods and a new techno-economic analysis is required (Jolliffe, 2018).

• Scalability: Moving from lab-scale to industrial production necessitates major investments in infrastructure and process improvement (Raval, 2018).

VII. The Future of Sustainable Pharmaceutical Production

The utilization of terephthalic acid derived from recycled plastics is a step toward a circular economy in medicines. Future trends include:

• Biotechnological Advancements: Expanding microbial fermentation to generate more pharmaceuticals such as citalopram or escitalopram from waste intermediates (Lundbeck, 2010).

• Regulatory Support: Governments may create incentives for green chemistry, such as “Section 45Q Tax Credit for Carbon Sequestration” in the USA (Jones, 2023).

• Industry Adoption: As consumer and investor demand for sustainability rises, pharmaceutical businesses will pursue environmentally friendly methods to improve market competitiveness (Insight, 2025).

• Circular Economy Integration: Scaling chemical recycling and bioconversion processes to meet the demands of industry, allowing pharmaceutical manufacturing to use plastic waste streams as normal feedstocks, reducing dependency on virgin petrochemicals and lowering environmental footprints (D’Adamo, 2019).

These developments collectively signal a future where pharmaceuticals can be manufactured more sustainably, supporting both environmental stewardship and global health objectives. 

VIII. Conclusion

The use of terephthalic acid derived from recycled PET plastics to make paracetamol is an excellent illustration of how pharmaceutical production can be made more sustainable. Diversifying paracetamol manufacturing to include PET plastic as a raw material makes a positive environmental impact by transforming trash into valuable medication via a biotechnological innovation (Johnson, 2025). Although potential commercialization issues with purity, scaling, regulation, and economic feasibility persist, they are currently dwarfed by the scientific triumph of creating medicine from plastic waste; a truly sustainable innovation. If businesses and regulators embrace green (bio)chemistry, such technologies may play an important role in establishing a circular, low-carbon pharmaceutical sector.

IX. Sources

AstraZeneca. (2020, January 22). AstraZeneca’s ‘Ambition Zero Carbon’ strategy to eliminate emissions by 2025 and be carbon negative across the entire value chain by 2030. AstraZeneca. https://www.astrazeneca.com/media-centre/press-releases/2020/astrazenecas-ambition-zero-carbon-strategy-to-eliminate-emissions-by-2025-and-be-carbon-negative-across-the-entire-value-chain-by-2030-22012020.html

Benyathiar, P., Kumar, P., Carpenter, G., Brace, J., & Mishra, D. K. (2022). Polyethylene terephthalate (PET) bottle-to-bottle recycling for the beverage industry: A review. Polymers, 14(12), Article 2366. https://doi.org/10.3390/polym14122366

Bohre, A., Jadhao, P. R., Tripathi, K., Pant, K. K., Likozar, B., & Saha, B. (2023). Chemical recycling processes of waste polyethylene terephthalate using solid catalysts. ChemSusChem, 16(14), Article e202300142. https://doi.org/10.1002/cssc.202300142

D’Adamo, I. (2019). Adopting a circular economy: Current practices and future perspectives. Social Sciences, 8(12), Article 328. https://doi.org/10.3390/socsci8120328

European Commission. (n.d.). Circular economy action plan. European Commission. Retrieved July 3, 2025, from https://environment.ec.europa.eu/strategy/circular-economy-action-plan_en

Johnson, N. W., Valenzuela-Ortega, M., Thorpe, T. W., Era, Y., Kjeldsen, A., Mulholland, K., & Wallace, S. (2025). A biocompatible Lossen rearrangement in Escherichia coli. Nature Chemistry. Advance online publication. https://doi.org/10.1038/s41557-025-01845-5

Jolliffe, H. G., & Gerogiorgis, D. I. (2018). Process modelling, design and technoeconomic evaluation for continuous paracetamol crystallisation. Computers & Chemical Engineering, 118, 224–235. https://doi.org/10.1016/j.compchemeng.2018.03.020

Jones, A. C., & Marples, D. J. (2023, August 25). The Section?45Q tax credit for carbon sequestration (CRS In Focus No. IF11455). Congressional Research Service. https://sgp.fas.org/crs/misc/IF11455.pdf

Lapa, H. M., & Martins, L. M. D. R. S. (2023). p-Xylene oxidation to terephthalic acid: New trends. Molecules, 28(4), Article 1922. https://doi.org/10.3390/molecules28041922

Lundbeck A/S. (2010). Intermediates for the preparation of citalopram and escitalopram (U.S. Patent No. 7,687,645?B2). U.S. Patent and Trademark Office. https://patents.google.com/patent/US7687645B2

Lundbeck & Co. A/S. (2005). Method for the preparation of 5?carboxyphthalide (U.S. Patent No. 6,888,009?B2). U.S. Patent and Trademark Office. https://patents.google.com/patent/US6888009B2

Prescott, L. F. (1996). Paracetamol (Acetaminophen): A critical bibliographic review. Taylor & Francis.

Raval, N., Tambe, V., Maheshwari, R., Deb, P. K., & Tekade, R. K. (2018). Scale-up studies in pharmaceutical products development. In R. K. Tekade (Ed.), Dosage form design considerations (pp. 669–700). Academic Press. https://doi.org/10.1016/B978-0-12-814423-7.00019-8

Santos, B. (2025, June 25). Scientists convert PET waste into paracetamol. Sustainable Plastics. https://www.sustainableplastics.com/news/scientists-convert-pet-waste-paracetamol

Schwab, S. T., Baur, M., Nelson, T. F., & Mecking, S. (2024). Synthesis and deconstruction of polyethylene-type materials. Chemical Reviews, 124(5), 2327–2351. https://doi.org/10.1021/acs.chemrev.3c00587

Swaminathan, R. (2024, March 22). Pharma needs a dose of sustainability. Outlook Business. https://www.outlookbusiness.com/opinions/pharma-needs-a-dose-of-sustainability-news-417354

The Insight Partners. (n.d.). Sustainable pharmaceutical packaging market [Market research report]. The Insight Partners. Retrieved July 4, 2025, from https://www.theinsightpartners.com/en/reports/sustainable-pharmaceutical-packaging-market

Thompson, T. (2025, June 23). Researchers turn plastic into paracetamol. Chemical & Engineering News. https://cen.acs.org/biological-chemistry/biotechnology/Researchers-turn-plastic-paracetamol/103/web/2025/06

Umdagas, L., Orozco, R., Heeley, K., Thom, W., & Al-Duri, B. (2025). Advances in chemical recycling of polyethylene terephthalate (PET) via hydrolysis: A comprehensive review. Polymer Degradation and Stability, 234, Article 111246. https://doi.org/10.1016/j.polymdegradstab.2025.111246

United Nations. (n.d.). The global goals: 17 sustainable development goals. United Nations. Retrieved July 3, 2025, from https://sdgs.un.org/goals

Wittayanukorn, S., Rosenberg, M., Schick, A., Hu, M., Wang, Z., Babiskin, A., Lionberger, R., & Zhao, L. (2020). Factors that have an impact on abbreviated new drug application (ANDA) submissions. Therapeutic Innovation & Regulatory Science, 54(6), 1372–1381. https://doi.org/10.1007/s43441-020-00163-x

About the Author

David Orchard-Webb, Ph.D., is a technical writer with broad interests including health & technology writing, plus extensive training and knowledge of biomedicine and microbiology. My Ph.D. and postdoc were in oncology and developing cancer medicines. I provide technical medical and other writing services for projects ranging from “knowledge automation” to pure pharma, to food safety, to the history of science, and everything in between. I also provide white papers, ebooks, meta-analysis reviews, editing, consulting, business, and market research-related activities in biomedicine, technology, and health. In addition to its well-known role in the development of medicines, I am a big believer in biotechnology’s ability to revolutionize industries such as food-tech, agtech, textiles & fashion.