White phosphorus: What is the chemical Israel is accused of using in Gaza and Lebanon?

The Israeli army has denied accusations that it used the toxic chemical in populated areas

An explosion over Gaza city on October 11 that Humans Rights Watch said was white phosphorus. Getty Images

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Israel has been accused of using white phosphorus in military operations in Gaza and Lebanon by the Human Rights Watch.

The NGO said it had verified videos taken in Lebanon and Gaza on October 10 and 11 that showed “multiple airbursts of artillery-fired white phosphorus over the Gaza city port and two rural locations along the Israel-Lebanon border”.

Israel has branded the accusations as “unequivocally false”.

The human rights group also shared videos showing “155mm white phosphorus artillery projectiles being used, apparently as smokescreens, marking, or signalling”.

Israel has carried out several strikes on the Gaza Strip since October 7 after Hamas killed about 1,200 people in a surprise attack in southern Israel. About 240 were taken hostage.

More than 11,200 people have since been killed in retaliatory Israeli strikes on Gaza.

Israel has also launched smaller-scale strikes on Hezbollah in southern Lebanon. The Lebanese Ministry of Agriculture has said that since October 8, 328 fires have been recorded in 52 towns in the area due to Israeli shelling, attributing many to the use of white phosphorus.

White phosphorus is a toxic substance that can be used for marking, signalling or as a smoke agent because it produces clouds of irritating white smoke. It also has an incendiary effect as it can spontaneously combust when exposed to oxygen.

It can also severely burn people and structures. White phosphorus can cause deep thermal and chemical burns to human skin.

HRW said even relatively minor burns from white phosphorus can be fatal. Survivors often have extensive scarring which tightens muscle tissue and lifelong physical disabilities.

“Any time that white phosphorus is used in crowded civilian areas, it poses a high risk of excruciating burns and lifelong suffering,” Lama Fakih, Middle East and North Africa director at Human Rights Watch said.

“White phosphorus is unlawfully indiscriminate when airburst in populated urban areas, where it can burn down houses and cause egregious harm to civilians,” Mr Fakih said.

White phosphorus can be legally used on battlefields for creating smoke screens to conceal movement. Its use against civilians is prohibited by Protocol III of the 1980 Convention on Certain Conventional Weapons. Israel, however, has not signed the protocol and is not bound by it.

The Israeli army has denied using the weapon.

“The current accusation made against the IDF regarding the use of white phosphorus in Gaza is unequivocally false,” the army said.

“The IDF has not deployed the use of such munitions.”

Israel has previously been accused of using white phosphorus in Gaza. During its 2008-2009 offensive on the strip, the Israeli military admitted to having used the toxic agent. In 2013, it said it would no longer use it in future conflicts.

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