International Day for the Preservation of the Ozone Layer of the hole in the ozone layer was observed 30 years after the protocol was signed. Due to the nature of the gases responsible for ozone depletion their chemical effects are expected to continue for between 50 to 100 years. International Day for the Preservation of the Ozone Layer September 16 was designated by the United Nations General Assembly as the International Day for the Preservation of the Ozone Layer. This designation had been made on December 19, 2000, in commemoration of the date, in 1987, on which nations signed the Montreal Protocol on Substances that Deplete the Ozone Layer.
United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances stereoisomers in EU Category 1. See also the article: drug precursors The salts of the substances listed in this Table whenever the existence of such salts is possible. The salts of the substances listed in this Table whenever the existence of such salts is possible. The salts of hydrochloric acid and sulphuric acid are specifically excluded from Table II. United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances The United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances of 1988 is one of three major drug control treaties currently in force. It provides additional