The choice of materials for catheter construction is critical from a toxicology standpoint. For instance, PVC catheters often contain plasticizers like di(2-ethylhexyl) phthalate (DEHP), which can have endocrine-disrupting effects. Polyurethane catheters are generally considered safer as they are less likely to leach harmful substances. However, the use of biocompatible materials that minimize the risk of adverse reactions is a growing area of research and development in this field.