International environmental law

International environmental law comprises the body of substantive international law and procedural rules that aim to protect the environment. Legal instruments have been adopted at both the regional and global level.

History of international environmental law

The first bilateral and multilateral agreements on environmental issues date back to the 1800s. They focused primarily on the protection of fisheries and the conservation of flora and fauna. The first international environmental arbitration case also concerned conservation issues. The Fur Seal Arbitration (1893) was a dispute between the United States and Great Britain in relation to Great Britain's alleged over-exploitation of fur seals outside its jurisdiction.

Trail Smelter (US v Canada) (1938) United Nations Reports of International Arbitral Awards Vol III, 1905–82, the famous transboundary pollution case, was a dispute between the United States and Canada over sulphur dioxide emissions from a smelter in Trail, British Columbia that were allegedly causing damage to forests and crops across the border in Washington. The case established the principle that states have a duty to prevent transboundary harm.

The establishment of the United Nations and specialist agencies with some environmental mandate also contributed

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