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.
Aarhus Protocol on Persistent Organic Pollutants housed 53 different country members and alliance. The protocol was amended on 18 December 2009, but the amended version has not yet come into force. As of May 2013, the protocol has been ratified by 31 states and the European Union. In the United States, the protocol is an executive agreement that does not require Senate approval. However, legislation is needed to resolve inconsistencies between provisions of the protocol and existing U.S. laws (specifically the Toxic Substances Control Act and the Federal Insecticide, Fungicide, and Rodenticide Act). The following substances are contained in the CLRTAP POPs Protocol. The document focuses