Before revision: Early international agreements were successful at addressing Global Environmental issues, such as Montreal Protocol, which banned Ozone depleting chemicals in 1987, with more recent agreements focusing on broader, more widely dispersed chemicals such as persistent organic pollutants in the Stockholm Convention on Persistent Organic Pollutants created in 2001, such as PCBs, and the Kyoto Protocol in 1997 which initiated colllaboration on addressing greenhouse gases to mitigate climate change.
After revision: Early international agreements were successful at addressing Global Environmental issues, such as Montreal Protocol, which banned Ozone depleting chemicals in 1987, with more recent agreements focusing on broader, more widely dispersed chemicals such as persistent organic pollutants in the Stockholm Convention on Persistent Organic Pollutants created in 2001, such as PCBs, and the Kyoto Protocol in 1997 which initiated collaboration on addressing greenhouse gases to mitigate climate change.