The fifth session of the Intergovernmental Negotiating Committee (INC-5) to combat plastic pollution kicks off in South Korea's Busan, with the diplomat chairing the difficult negotiations urging nations to "meet an existential challenge." "This conference is about far more than drafting an international treaty. It is about humanity racing to meet an existential challenge," Ecuadorian diplomat Luis Vayas Valdivieso says in his opening remarks. IMAGES AND SOUNDBITES