Human rights groups and The New York Times say they have documented Israel's use of the chemical white phosphorus over civilian areas in Lebanon. It is a substance that can cause severe burns, respiratory issues and death.
The New York Times reported Saturday that Israel used white phosphorus in the Lebanese town of Nabatieh May 30 by verifying social media videos.
Israel re-started strikes on the Iran-backed militant group Hezbollah in Lebanon shortly after Israel and the U.S. jointly struck Iran at the end of February. Hezbollah had first re-ignited the cross-border conflict with projectiles fired at communities in Northern Israel in early March. While Lebanon and Israel agreed to a ceasefire Wednesday, Hezbollah rejected that agreement. Since then, continued Israeli airstrikes have killed nine people, including three members of the Lebanese military.
White phosphorus is not banned under international law, but it is illegal to use the chemical in and near populated areas since it can cause widespread harm. Israel has been accused by the international human rights community for decades of using the substance in a way that puts civilians in danger.
"It can create cruel injuries—life long injuries," says Ramzi Kaiss, a Lebanon researcher with the international NGO Human Rights Watch (HRW). "Or cause death."
What is white phosphorus?
White phosphorus is a solid, waxy chemical that ignites instantly when combined with oxygen. The Chemical Weapons Convention, an arms control treaty signed by more than 190 states, that focuses on the production and use of chemical weapons, designates white phosphorus an incendiary agent rather than a chemical weapon.
Countries can use the substance to create smoke screens, and the Israel Defense Forces say it's for this purpose that it uses the substance in some of its artillery shells. White phosphorus can also be used to mark military targets for subsequent strikes.
But the Chemical Weapons Convention does prohibit such incendiary agents from being used in civilian areas, and that is what Human Rights Watch and Amnesty International have accused Israel of doing.
NPR has not independently verified these claims and Israel denies using white phosphorus in a way that violates the law.
Why is white phosphorus dangerous to civilians?
The substance can cause indiscriminate damage. One white phosphorus artillery projectile, according to Human Rights Watch, can cause it to fall across an area with a diameter of between 125 and 250 meters, if it bursts in the air overhead.
Once on the ground, the substance sticks to skin and clothes. It can cause severe burns that penetrate through bones, producing particles that damage eyes and the upper respiratory tract. These effects can be deadly.
White phosphorus can be difficult to extinguish and can re-ignite when re-exposed to oxygen.
"It can still burn for several days or weeks later," said Budour Hassan, Amnesty International's researcher on Israel and Palestine. "Our investigators visited places in Gaza days after, where white phosphorus was air-dropped, and it was still there."
What do we know about Israel's current and past use of white phosphorus?
The New York Times reported Israel used white phosphorus in Nabatieh, which has a population of roughly 40,000. It also verified footage of white phosphorus being used near the city of Tyre as well as three other towns since March. Human Rights Watch also said it had separately verified the use of incendiary weapons over homes in southern Lebanon on March 3.
The rights advocacy group also said the Israeli military used the substance in Lebanese civilian areas during a previous conflict with Hezbollah in 2023, as well as in Gaza. HRW's Kaiss said white phosphorus drove Lebanese civilians from their homes near the border with Israel and left them displaced.
A previous Human Rights Watch investigation found Israel used white phosphorus in Gaza in 2009. Israel did pledge to significantly reduce its use of the substance in 2013.
Israel is not alone in deploying white phosphorus. The United States has also used the substance, most recently in Iraq in 2017, which the U.S. said it did to provide cover for civilians fleeing west Mosul as the U.S. and Iraqi forces fought the Islamic State inside the city.
The Washington Post reported in 2023 that the U.S. had provided the white phosphorus used by Israel's military in Lebanon.
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