The Bacterial Endotoxin Test (BET) is a standard practice for quality assurance in the biopharmaceutical industry due to several reasons:

1. Patient Safety: Bacterial endotoxins, also known as pyrogens, can cause severe adverse reactions in humans, including fever, inflammation, and even septic shock. The presence of endotoxins in pharmaceutical products can pose significant risks to patient safety. The BET helps ensure that sterile products, particularly injectable drugs and implantable medical devices that come into contact with the bloodstream or spinal fluid, are free from harmful levels of endotoxins 
2. Regulatory Compliance: Regulatory agencies, such as the U.S. Food and Drug Administration (FDA), require the testing of pharmaceutical products for endotoxins to ensure compliance with safety standards. The USP <85> Bacterial Endotoxins Test provides guidelines for endotoxin testing, and adherence to these standards is essential for regulatory approval and market authorization 
3. Quality Control: The BET is an integral part of quality control in the biopharmaceutical industry. It helps identify and control potential sources of endotoxin contamination during the manufacturing process, including raw materials, water used in production, equipment, and packaging components. By implementing appropriate control measures, manufacturers can ensure the production of safe and high-quality pharmaceutical products 
4. Process Validation: The BET is used for process validation to ensure that manufacturing processes effectively remove or inactivate endotoxins. It helps evaluate the efficiency of purification methods, sterilization processes, and cleaning procedures to minimize the risk of endotoxin contamination .
5. Risk Management: The presence of endotoxins can be a result of various factors, including raw materials, water sources, formulation excipients, and manufacturing equipment. The BET allows for the identification and mitigation of potential risks associated with endotoxin contamination. By implementing appropriate control measures and conducting routine testing, manufacturers can minimize the risk of endotoxin-related issues in their products.