(20)The quaternary treatment necessary to remove micropollutants from urban wastewater will involve additional costs, such as costs related to monitoring and the cost of new advanced equipment to be installed in certain urban wastewater treatment plants. In order to cover those additional costs and in accordance with the polluter-pays principle expressed in Article 191(2) TFEU, it is essential that the producers placing on the Union market products containing substances which, at the end of their life, are found as micropollutants in urban wastewater take responsibility for the additional treatment required to remove those substances, generated in the context of their professional activities. A system of extended producer responsibility is the most appropriate means to achieve this, as it would limit the financial impact on the taxpayer and water tariffs, while providing an incentive to develop greener products. In this context, extended producer responsibility should apply regardless of whether the products are placed on the market, or whether their individual components were manufactured in a Member State or third country, or whether the producers have a registered office in the Union or the product is placed on the market via a digital platform. Pharmaceuticals and cosmetic residues currently represent the main sources of micropollutants found in urban wastewater requiring quaternary treatment. Therefore, extended producer responsibility should apply to those two product groups. On the basis of the results of the urban wastewater monitoring and the most recent scientific data, the Commission should regularly evaluate whether other products should be included in the extended producer responsibility system.