Benzoyl impurities refer to unwanted substances that may be present in benzoyl-containing products. These impurities can negatively impact the quality and efficacy of the product, and may even pose health risks to consumers. It is important for manufacturers to carefully monitor and control the presence of benzoyl impurities to ensure product safety and effectiveness. Analytical techniques such as HPLC and GC can be used to detect and quantify these impurities.