“…In other words, the Union provides for the approximation of national laws of the Member States and exhaustively regulates a specific field, thereby pre-empting the national competence to take independent actions therein. 18 In Tedeschi, the question concerned Directive 74/63/EEC, 19 providing for approximation of the levels for undesirable substances and products in feeding stuff, whereby those levels had been totally harmonised. As concluded by the Court in Tedeschi, 16 the justifications set out in Article 36 TFEU, in relation to the free movement of goods are, [N]ot designed to reserve certain matters to the exclusive jurisdiction of Member States but permits national laws to derogate from the principle of the free movement of goods to the extent to which such derogation is and continues to be justified for the attainment of the objectives referred to in that Article.…”