Increasing consumption of pharmaceuticals leads also to higher release of its non-metabolized residues into environment, mostly hydrosphere. Some of these substances may reach also processed drinking water. Although it is found in traces, it causes public concern as it can represent a non-targeted and unwanted medication. Toxicologists and public health authorities are appealed to assess potential health risks carefully and to communicate the risk adequately to public. As health risks assessment of environmental exposure to pharmaceuticals is a new field of expertise, its methodology has not been unified and standardized yet, but several different procedures have been proposed and used. The paper provides overview of these methods.