montreal protocol to reduce production of chlorofluorocarbons was assigned in
Montreal Protocol The Montreal Protocol on Substances that Deplete the Ozone Layer (a protocol to the Vienna Convention for the Protection of the Ozone Layer) is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances that are responsible for ozone depletion. It was agreed on 26 August 1987, and entered into force on 26 August 1989, followed by a first meeting in Helsinki, May 1989. Since then, it has undergone eight revisions, in 1990 (London), 1991 (Nairobi), 1992 (Copenhagen), 1993 (Bangkok), 1995 (Vienna), 1997 (Montreal), 1998 (Australia), 1999 (Beijing) and 2016 (Kigali, adopted, but not in force).[1][2] As a result of the international agreement, the ozone hole in Antarctica is slowly recovering.[3] Climate projections indicate that the ozone layer will return to 1980 levels between 2050 and 2070.[4][5] Due to its widespread adoption and implementation it has been hailed as an example of exceptional international co-operation, with Kofi Annan quoted as saying that "perhaps the single most successful international agreement to date has been the Montreal Protocol".[6][7] In comparison, effective burden sharing and solution proposals mitigating regional conflicts of interest have been among the success factors for the ozone depletion challenge, where global regulation based on the Kyoto Protocol has failed to do so.[8] In this case of the ozone depletion challenge, there was global regulation already being installed before a scientific consensus was established. Also, overall public opinion was convinced of possible imminent risks.[9][10]
Chemical weapons in World War I The earliest military uses of chemicals were tear-inducing irritants rather than fatal or disabling poisons. During World War I, the French army was the first to employ gas, using 26 mm grenades filled with tear gas (ethyl bromoacetate) in August 1914. The small quantities of gas delivered, roughly 19 cm³ per cartridge, were not even detected by the Germans. The stocks were rapidly consumed and by November a new order was placed by the French military. As bromine was scarce among the Entente allies, the active ingredient was changed to chloroacetone.[7]