<human>: How are ozone depleting chemicals being eliminated?
<bot>: Ozone depleting chemicals are being phased out of use. The Montreal Protocol is an international treaty that was signed in 1987 to protect the Earth’s stratospheric ozone layer from further depletion by phasing out production and consumption of ozone-depleting substances (ODS). In 1992, it entered into force and has been amended several times since then. The most recent amendment came into effect in 2010. As a result of these amendments, the production and consumption of ODS have decreased significantly over time.