8. In order to take account of scientific and technical progress, the Commission may adopt delegated acts in accordance with Article 64 to supplement this Regulation in order to determine the conditions under which the sum of the concentrations referred to in paragraph 4 of this Article shall not apply to recycled materials or to product loops which are in a closed and controlled chain, as well as to determine the packaging types or formats of packaging, based on the packaging categories listed in Table 1 of Annex II to this Regulation, which shall be exempted from the requirements laid down in that paragraph. Such delegated acts shall be justified on the basis of a case by case analysis, time-limited, provide for appropriate marking and information requirements, and contain requirements for regular reporting in order to ensure that the exemption is regularly reviewed. Delegated acts adopted in accordance with this paragraph shall only be adopted to amend derogations established in Decisions 2001/171/EC and 2009/292/EC.