ECOWAS (f) REVISED TREATY the control of narcotics, hazardous and toxic wastes, nuclear materials, radioactive products or any other material used in the development or exploitation of nuclear energy. 5. Member States shall not so exercise the right to introduce or continue to execute the restrictions or prohibitions referred to in paragraph 3 of this Article as to stultify the free movement of goods envisaged in paragraph 1 of this Article. ARTICLE 42 DUMPING 1. Member States undertake to prohibit the practice of dumping goods within the Community. 2. Forthepurposes of thisArticle, "dumping" means thetransfer of goodsoriginating in a Member State to another Member State for sale: (a) at a pricelowerthanthecomparable pricechargedfor similargoodsin the Member States where such goods originate (due allowance being made for the differences in the conditions of sale or in taxation or for any other factors affecting the comparability of prices); and (b) undercircumstances likely to prejudice the production of similargoodsin that Member State. 3. Intheevent ofalleged dumping theimporting Member State shall appeal toCouncil to resolve the matter. 4. Council shall consider the issue and take appropriate measures to determine the causes of the dumping. ARTICLE 43 MOST FAVOURED NATION TREATMENT 1. Member States shall accord to one another in relation to trade between them the most favoured nation treatment. In no case shall tariff concessions granted to a third country bya Member State bemore favourable than those applicable under this Treaty. 2. Any agreement between a Member State and a third country under which tariff concessions are granted, shallnot derogate from the obligations of that Member State under this Treaty. 3. Copies of such agreements referred to in paragraph 2 of this Article shall be transmitted by the Member States which are parties to them, to the Executive Secretariat of the Community. 29