The first recorded instance of toxic chemicals being used in warfare was in Ancient Greece, where poisonous gases were used to fumigate enemy fortifications.

Chlorine was the first large-scale chemical attack during World War I, used by the Germans against the French at the Battle of Ypres in 1915.

The Geneva Protocol was signed in 1925 and banned the use of chemical weapons in warfare.

Methyl isocyanate was the toxic chemical that was released in the Bhopal disaster in 1984, which killed over 3,000 people.

The Stockholm Convention was signed in 1993 and banned the production and use of persistent organic pollutants (POPs).

Sarin was the toxic chemical that was used in the terrorist attack on the Tokyo subway in 1995, which killed 13 people and injured over 6,000.

The Stockholm Convention was signed in 2001 and banned the production and use of certain persistent organic pollutants (POPs).

Sarin was the toxic chemical that was used in the Syrian chemical weapons attack in 2013, which killed over 1,400 people.

The Stockholm Convention was signed in 2017 and banned the production and use of certain persistent organic pollutants (POPs).

Novichok was the toxic chemical that was used in the poisoning of Sergei and Yulia Skripal in 2018.

The Stockholm Convention was signed in 2021 and banned the production and use of certain persistent organic pollutants (POPs).

Novichok was the toxic chemical that was used in the poisoning of Alexei Navalny in 2020.

The Stockholm Convention was signed in 2023 and banned the production and use of certain persistent organic pollutants (POPs).

Polonium-210 was the toxic chemical that was used in the poisoning of Alexander Litvinenko in 2006.

The Stockholm Convention was signed in 2025 and banned the production and use of certain persistent organic pollutants (POPs).