Pharmaceutical medicines play a critical role in human and animal health. In recent years, increasing evidence indicates that pharmaceuticals are accumulating in the environment and creating risks to human health and the environment. To address these risks, the pharmaceutical industry along with other stakeholders have committed to developing and implementing solutions to reduce the impact of pharmaceuticals in the environment (PiE).
This bulletin summarizes the performance of Axine’s electrochemical oxidation technology for treating active pharmaceutical ingredients (APIs) commonly found in clean-in-place (CIP) rinse streams and wastewater effluent generated by pharmaceutical manufacturing facilities. APIs tested by Axine include antibiotics, antimicrobials, pain and chemotherapy medicines. In all cases, the results show that Axine’s technology treated APIs to below site requirements, below Predicted No-Effect Concentration (PNEC¹) values and/or below analytical detection limits².
Pharmaceuticals can reach the environment through several pathways including use and excretion by humans and animals, disposal of unused or expired medication and effluent from pharmaceutical manufacturing facilities. Axine Water Technologies has created a new standard for addressing the third pathway to eliminate APIs in manufacturing wastewater.
The Axine system oxidizes the IPA to trace levels of byproduct gases including hydrogen, oxygen and carbon dioxide, which are vented to the atmosphere. No solid or liquid wastes are generated, and no hazardous chemicals are utilized.
APIs in wastewater are challenging to treat with conventional technologies because they are highly stable, often recalcitrant and non-biodegradable. In many cases, conventional wastewater technologies such as biological, sorption and advanced oxidation processes (AOP) are ineffective at treating APIs to the levels required to minimize impact to the environment. Frequently, pharmaceutical plants have no other option but to truck API contaminated streams off-site so the APIs can be thermally oxidized in an incinerator.
Axine has commercialized a unique, proprietary electrochemical oxidation technology ideally suited to oxidize all types of APIs in pharmaceutical wastewater to below PNEC levels. Axine’s technology applies electricity to solid state electrodes made from advanced catalyst materials. The Axine process mineralizes and destroys all types of APIs to below PNEC levels through multiple oxidation mechanisms.
Axine’s technology does not use hazardous chemicals and does not produce any solid or liquid waste. By comparison, conventional AOP technologies (e.g. ozone and hydrogen peroxide) may not be able to achieve complete destruction of APIs to meet stringent PNEC values and avoid producing toxic oxidation by-products. Conventional AOP technologies also require the use of hazardous chemicals.
Axine packages its electrochemical oxidation technology with other wastewater processes (e.g membranes, filtration, etc.) to provide complete turnkey solutions under a service model with performance guarantees. By taking this approach, Axine provides pharmaceutical manufacturers with a robust solution to achieve risk quotients less than 1 and low PNEC levels for the most ecotoxic APIs.
Axine has conducted treatability tests on a wide range of APIs commonly produced by the pharmaceutical industry with molecular weights from less than 200.00 g/mol to greater than 800.00 g/mol. Select test results are summarized below.
Treatability testing was conducted on a CIP rinse stream with background COD of > 3,000 mg/L and 7,000 µg/L of an antimicrobial API. The antimicrobial, which is toxic to aquatic ecosystems, has a multiple-ring structure and a molecular weight of more than 500 g/mol. As shown in Table 1 and Figure 1, Axine successfully treated the API to > 99.2% reduction or < 50 µg/L, which is below the 70 µg/L on-site treatment requirement for discharge to sewer.
Treatability testing was conducted on model wastewater containing deionized (DI) water with 100,000 µg/L of Amoxicillin and a COD of 134 mg/L. Amoxicillin is a common antibiotic with a molecular weight of 365.40 g/mol. As shown in Table 2 and Figure 2, Axine successfully treated the Amoxicillin to > 99.9% reduction or < 0.1 µg/L, which is below the PNEC value of 0.25 µg/L and the analytical detection limit of 0.1 µg/L.
Treatability testing was conducted on CIP process rinse water with 7,800 µg/L of a chemotherapy API and background COD of 19,920 mg/L. The API has a molecular weight of over 800 g/mol. As shown in Table 3 and Figure 3, Axine successfully treated the chemotherapy medicine to > 99.3% reduction or < 50 µg/L, which is well below the plant treatment target of < 200 µg/L.
Treatability testing was conducted on model wastewater with a background solvent matrix and 102,000 µg/L of Acetaminophen (pain medicine), 1,320,000 µg/L of Ampicillin (antibiotic), 71,000 µg/L of Atorvastatin (cardiovascular disease prevention), 94,000 µg/L of Atenolol (beta blocker) and 75,000 µg/L of Roxithromycin (antibiotic). Molecular weights ranged from 151.16 to 837.05 g/mol. This test was designed to simulate conditions where waste streams contain multiple APIs. As shown in Table 4, Axine successfully treated all APIs to > 99.999% reduction, below PNEC values and below analytical detection limits.
Table 4: API concentrations before and after Axine treatment in a multiple API blend AValues per Temple University’s Water and Environmental Technology (WET) Center PNEC list, 2019 BValues per AMR Industry Alliance’s recommendation, 2019 *Values indicate the analytical detection limits of these compounds
The selected API treatability results presented in this bulletin demonstrate the performance of Axine’s technology for treating diverse APIs to below site requirements, below PNEC values and/or below analytical detection limits. Axine’s technology and service delivery model provide pharmaceutical manufacturers with a solution capable of treating all types of APIs at high performance and low cost compared to conventional AOP and other technologies. Axine’s technology can be applied to a range of pharmaceutical applications including treating APIs and other organics in CIP rinse streams to avoid off-site incineration, pretreating API contaminated streams before on-site wastewater treatment and treating APIs in whole plant effluent prior to discharge.