Related Rule
Netherlands
Practice Relating to Rule 72. Poison and Poisoned Weapons
The Military Manual (1993) of the Netherlands states: “It is prohibited to use poison or poisoned weapons. This includes a prohibition to poison or contaminate water supplies.” 
Netherlands, Toepassing Humanitair Oorlogsrecht, Voorschift No. 27-412/1, Koninklijke Landmacht, Ministerie van Defensie, 1993, p. IV-6.
The Military Handbook (1995) of the Netherlands states: “It is prohibited to use poison and poisoned weapons.” 
Netherlands, Handboek Militair, Ministerie van Defensie, 1995, p. 7-39.
The Military Manual (2005) of the Netherlands states: “It is … prohibited to use poison or toxic weapons. This includes a prohibition of poisoning or contaminating the water supply.” 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 0455.
In its chapter on non-international armed conflict, the manual states:
It is prohibited to use weapons causing unnecessary suffering or excessive injury, or that are indiscriminate. This means that biological, chemical, toxic or intoxicating weapons … are forbidden. 
Netherlands, Humanitair Oorlogsrecht: Handleiding, Voorschift No. 27-412, Koninklijke Landmacht, Militair Juridische Dienst, 2005, § 1038.
The Definition of War Crimes Decree (1946) of the Netherlands includes the “poisoning of wells” in its list of war crimes. 
Netherlands, Definition of War Crimes Decree, 1946, Article 1.
Under the International Crimes Act (2003) of the Netherlands, “employing poison or poisoned weapons” is a crime, when committed in an international armed conflict. 
Netherlands, International Crimes Act, 2003, Article 5(5)(g).