Bromochloromethane such as halon 1211 and 1301 were developed. Due to its ozone depletion potential its production was banned from January 1, 2002, at the "Eleventh Meeting of the Parties for the Montreal Protocol on Substances that Deplete the Ozone Layer". It can be biologically decomposed using the hydrolase enzyme alkylhalidase by the reaction: In the "Enter the Matrix" video game, the player can find a "Chloro-Bromo Methane Gun", which is used as a fire extinguisher. It fires a pressurized cartridge of CBM gas to put out fires. However, due to its chemical properties, firing a cartridge near people causes their
Montreal Protocol Antarctic Survey scientists Joe Farman, Brian Gardiner and Jonathan Shanklin published results of abnormally low ozone concentrations above Halley Bay near the South Pole. They speculated that this was connected to increased levels of CFCs in the atmosphere. It took several other attempts to establish the Antarctic losses as real and significant, especially after NASA had retrieved matching data from its satellite recordings. The impact of these studies, the metaphor 'ozone hole', and the colourful visual representation in a time lapse animation proved shocking enough for negotiators in Montreal, Canada to take the issue seriously. Also in 1985, 20 nations,