Pendimethalin is a selective pre-emergent herbicide widely used in agriculture to control annual grasses and broadleaf weeds. However, during the manufacturing process or storage, impurities may be formed, which can affect the efficacy and safety of the herbicide. Some of the potential impurities in pendimethalin are degradants, isomers, and other related compounds that may have toxicological or environmental concerns. Analytical methods are used to identify and quantify these impurities to ensure the quality and safety of the herbicide product.