By derogation from the provisions of 2.2.9.1.10, last sentence and notwithstanding the provisions of 2.3.5, substances which cannot be assigned to other classes of ADR or to other entries of Class 9, and which are not identified in Council Directive 67/548/EEC of 27 June 1967 on the approximation of laws, regulations and administrative provisions relating to the classification, packaging and labelling of dangerous substances, as amended, as substances to which letter N “Environmentally hazardous" (R50; R50/53; R51/53) has been allocated, are not subject to ADR.