RT null T1 World Dental Federation K1 mercury YR 2009 FD 2009-02 LK https://wedocs.unep.org/handle/20.500.11822/12768 UL https://wedocs.unep.org/handle/20.500.11822/12768 NO World Dental Federation NO https://www.unep.org/chemicalsandwaste/Portals/9/Mercury/Documents/PartneshipsAreas/PartneshipsLetters/World%20Dental%20Federation%20%20letter.pdf DS UN Environment Document Repository RD Sep 16, 2026