Wpływ środków kontrastujących na środowisko naturalne

Contrast media are used in imaging modalities such as x-rays, ultrasound, computed tomography and magnetic resonance. Contrast media enhance tissues to help make a diagnosis. This review coversinformation about types of contrast agents, their chemical compositions, routes of administration, imaging applications and biological effects. Scientific studies indicate the presence of contrast agents in wastewater. They are not fully removed in conventional treatment processes and therefore enter surface waters with treated wastewater. At the University Clinical Center in Gdansk, the most frequently used contrast agents are iodinated contrast media, secondly gadolinium contrast agents. Iodinated contrast media are pharmaceuticals which are metabolically stable during their passage through the body and are excreted into wastewater. All transformation products of the iodinated contrast medium iopromide were found in municipal effluents because of their formation during biological wastewater treatment. Four products formed at the end of the transformation pathway were also found in bank filtrate and in groundwater of a wastewater irrigation area. The contrast agents themselves do not carry a risk of toxicity, but it can be predicted from the chemical structure that the transformation products may be toxic and mutagenic. On the other hand, MRI contrast agents can cause histopathological changes. Gadolinium deposition in tissues has been proven. The toxicity of gadolinium is well known. Further research on the toxicity of gadolinium contrast agents is needed to be able to prevent unwanted consequences and produce safe contrast agents. Conventional methods currently used do not ensure high efficiency of removing pharmaceuticals from wastewater, which makes it necessary to introduce advanced methods of treatment. The article presents strategies for removal of the compounds in wastewater-treatment plants.