By Brian Okoth
On Tuesday, Palestine accused Israel of using white phosphorus bombs in striking populated areas in western Gaza.
Israel has been hitting Gaza with airstrikes after Hamas fighters launched an offensive against Israel on Saturday.
The fight, which continues to leave a trail of destruction, has thus far caused the deaths of hundreds of people from both sides.
Concerns arose recently after Palestine alleged that Israel had resorted to a restricted weapon under the international humanitarian law, a set of rules seeking to limit the effects of armed conflict.
Hundreds of people in Gaza sustained respiratory problems, including suffocation, Anadolu Agency reported on Wednesday, citing medical sources.
Israel was yet to respond to the allegations as of the time of publishing this article. But what is the white phosphorus, and why is its use restricted?
Burns
White phosphorus is a wax-like substance that ignites instantly when it comes into contact with oxygen. It is often yellowish, and smells like garlic.
It is mainly used as a weapon due to its quick burning characteristic. Its initial purpose in armed conflict was to illuminate targets during night raids.
It is also used to create smokescreens during the day because it produces a lot of smoke while burning.
The substance was used in past armed conflicts, including both World Wars, and in Afghanistan, Syria and Gaza, according to the Human Rights Watch.
The first attempt at regulating the international use of such a weapon was in 1933.
The United Nations classifies the white phosphorus as an incendiary weapon, meaning it is designed to set fire to objects, cause burn or respiratory injury to people through the action of flame, heat, or both.
The other substance classified as an incendiary weapon is Napalm, a mixture of gelling agent and petrochemical.
In the 1970s, the UN started efforts to address the use of incendiary weapons during armed conflicts.
'Arms viewed with horror'
In 1972, the UN General Assembly adopted a resolution referring to incendiary weapons as "arms viewed with horror."
"The massive spread of fire through incendiary weapons is largely indiscriminate in its effects on military and civilian targets," the UN said at the time, accusing militaries of breaching civilian protection rights.
"The long-upheld principle of the immunity of non-combatant appears to be receding from the military consciousness. These trends have grave implications for the world community," the UN added.
Eight years later, the UN adopted the Convention on Prohibitions or Restrictions on the Use of Certain Conventional Weapons Which May Be Deemed to Be Excessively Injurious or to Have Indiscriminate Effects. The white phosphorus was listed among the restricted weapons.
The 1980 resolution banned the use of incendiary weapons on civilians and military establishments located within populated areas.
The protocol also prohibits the use of incendiary weapons on forest or other plants, unless the vegetation is used to "conceal military objects."
Whereas the white phosphorus can be used on battlefields, it is completely prohibited in civilian settlements under the international humanitarian law.
Effects of white phosphorus
Once ignited, the white phosphorus is very difficult to extinguish, as it sticks on many surfaces, including skin and clothing.
The white phosphorus bomb, which can ignite up to 815 degrees Celsius, can burn the human body to the bone, cause respiratory failure, infections, shock or even failure of key organs such as the heart, liver and kidney. Death is also a high possibility.
"Burn injuries, whether sustained directly from the action of incendiaries or as a result of fires initiated by them, are intensely painful and require exceptional resources for their medical treatment that are far beyond the reach of most countries," the UN said in 1972.
White phosphorus smoke also causes eye and respiratory tract irritation, according to health journals.
Its long-term effects could be impaired mobility and psychological harm, the Human Rights Watch says.
The fires caused by white phosphorus bomb can also destroy civilian structures and property, damage crops and kill livestock.
Due to a scarcity of healthcare providers during armed conflict, victims of white phosphorus attacks could be severely affected by the burns.
