Comets are thought to have survived unchanged since the early days of the solar system, so the discovery of methyl
isocyanate suggested it had been present on the comet since then and didn't form on a planet.
Studies have
suggested serious insufficiencies in the safety measures at the installation, including lack of safety valves to prevent the mixing of water into the Methyl
isocyanate tanks which started the evolution of the toxic gas, and the failure of scrubbers to treat the gas leak — apparently they were out of service for repair.