What is white phosphorus — and why is it so controversial? Israel accused of using it in Gaza

The Israeli military deployed white phosphorus, a controversial and lethal chemical substance, in its war against Hamas, putting civilians at risk of life-threatening burns, according to the Human Rights Watch (HRW).

The organization, an international nonprofit, said it verified video footage from multiple locations — one in Gaza, a densely populated area, and two on the Israel-Lebanon border — depicting the chemical’s signature airbursts, according to an Oct. 12 statement.

“Any time that white phosphorus is used in crowded civilian areas, it poses a high risk of excruciating burns and lifelong suffering,” Lama Fakih, HRW’s director of Middle East and North Africa, said in the statement.

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

A United Nations spokesperson said on Oct. 11 that it had not verified claims of the substance being used by Israel.

What is white phosphorus?

Produced from phosphate embedded in rocks, white phosphorus is a toxic substance that’s used in fertilizers, cleaning compounds as well as military tools and weapons, according to the Centers for Disease Control and Prevention.

The substance spontaneously ignites upon coming into contact with oxygen, creating a white cloud and a garlic-like odor.

“On the one hand this means it can be useful for legitimate military purposes — like creating a smokescreen to cover troop movement,” Rebecca Hamilton, a professor of law at American University, told McClatchy News.

“But it creates horrific injuries — burns can go down to the bone, with wounds that may reignite when bandages are removed,” Hamilton, who specializes in international human rights law, said.

Why is it controversial?

White phosphorus is controversial because of its ability to cause severe harm to civilian populations, according to HRW.

When the substance ignites, it produces an intense heat of 1,500 degrees Fahrenheit, more than seven times hotter than the temperature of boiling water.

People exposed to white phosphorus can suffer severe and sometimes deadly bone-deep burns. It can cause organs to shut down, and burns on just 10% of the body can be fatal, HRW said. Those who don’t die can suffer from scarring, mobility issues and psychological trauma.

Is it illegal?

“Unlike some weapons that cause this level of human suffering, white phosphorous is not banned outright under international law,” Hamilton said. “But (its) lawful use is limited to specific circumstances.”

Under the United Nation’s Convention on Certain Conventional Weapons, it is illegal to drop incendiary weapons on “concentrations of civilians.”

But the weapons can still legally be used for “legitimate military purposes,” such as a smoke screen, Hamilton said.

“In addition, Israel is not a party to the Convention, although it is still bound by more general obligations of international humanitarian law, like the obligation to take reasonable precautions to protect civilians,” Hamilton said. “The use of white phosphorous in an area as densely populated as Gaza would violate this obligation.”

Past use

Militaries have used white phosphorus for decades, sometimes deploying it solely to veil their movements, while other times targeting people with it.

The Soviet Union made “extensive use” of the chemical substance during World War II, filling grenades, bombs and missiles with it, according to a 1953 CIA report.

The United States admitted to using white phosphorus in Iraq in 2004 in what a Pentagon spokesperson called a “shake and bake” mission, according to NPR.

A U.S.-led military coalition also deployed white phosphorus weapons in Syria and Iraq in its war against ISIS in 2017, according to HRW.

Israel, too, previously used the substance during a 2008-09 offensive in Gaza. Israeli officials said the white phosphorus munitions were only deployed as smoke screens, though HRW documented “dozens of civilian casualties.”

A subsequent United Nations report found the Israeli military’s use of white phosphorus in “built-up areas” was “systematically reckless.”

In response to global pushback, the Israeli military vowed to stop using white phosphorus in 2013, according to the BBC.

Further context

The Israeli government declared war on Hamas, the Islamic militant organization that rules Gaza, following Hamas’ Oct. 7 attack on southern Israel that left over 1,300 people, including many civilians, dead.

President Joe Biden, in an Oct. 11 speech, called it “the deadliest day for Jews since the Holocaust.”

Following Hamas’ attack, the Israeli military began launching airstrikes into the Gaza Strip, a seaside Palestinian territory populated with 2.1 million people, killing 1,537 people, including 500 children, according to Palestinian health officials.

Israeli Defense Minister Yoav Gallant also ordered a “complete siege” of the strip, according to the Times of Israel. Food, water, fuel and electricity have been cut off.

“We are fighting human animals and we are acting accordingly,” Gallant said.

International humanitarian organizations have called on both sides to avoid civilian casualties.

“The human misery caused by this escalation is abhorrent, and I implore the sides to reduce the suffering of civilians,” Fabrizio Carboni, the regional director for the Near and Middle East for the Red Cross, said in a statement.