International Labour Organization, Convention concerning the Prohibition and Immediate Action for the Elimination of the Worst Forms of Child Labour (Adopted 17 June 1999, entered into force 19 Nov 2000) No. 182

The Worst Forms of Child Labour Convention is one of the core ILO conventions.  Ratification requires a country to take immediate action to eliminate the worst forms of child labor.  The worst forms of child labour are defined in Article 3 to include "the use, procuring or offering of a child for illicit activities, in particular for the production and trafficking of drugs as defined in the relevant international treaties".