Routes into the Environment
There are three main routes by which pharmaceutical molecules enter the environment, which are shown in Figure 1:
- Normal patient use;
- Improper disposal of unwanted pharmaceuticals and related medical devices such as patches, implants etc. into landfill or water courses;
- Point source pollution at sites of manufacture/formulation.
A fourth route which is starting to become more prevalent (or at least better detected) is the illegal or off-label use of pharmaceuticals resulting in accumulation in unintended species such as plants and animals.