The International Day Against Drug Abuse and Illicit Trafficking is a United Nations International Day against drug abuse and the illegal drug trade. It is observed annually on 26 June, since 1989. The date June 26 is to commemorate Lin Zexu’s dismantling of the opium trade in Humen, Guangdong, ending on June 25, 1839, just before the First Opium War in China. The observance was instituted by General Assembly Resolution 42/112 of 7 December 1987.

Source: Dayspedia.com