White phosphorushas a significant, incidental, incendiary effect that can severely burn people and set structures, fields, and other civilian objects in the vicinity on fire. The potential for harm to civilians is magnified by Gaza's high population density, among the highest in the world.

Under the Geneva Convention, which are the statutory implementation of the customary law of war, it is forbidden to deliberately attack civilians or bona-fide civilian structures, dwellings, and places used for civilian purposes, such as hospitals, religious structures, and schools. It therefore follows that the use of any form of weapon to deliberately attack civilians or deliberately attack unquestionably civilian targets unoccupied by military forces is a war crime, and in violation of the laws of war.

The problem is it covers such a wide area that when the white phosphorus wafers come down, over 100 in each artillery shell, they burn everything they touch and they don't stop burning until they are done.

Human Rights Watch believes that the use of white phosphorus in densely populated areas of Gaza violates the requirement under international humanitarian law to take all feasible precautions to avoid civilian injury and loss of life.

Air bursting of white phosphorus artillery spreads 116 burning wafers over an area between 125 and 250 meters in diameter, depending on the altitude of the burst, thereby exposing more civilians and civilian infrastructure to potential harm than a localized ground burst.

In addition, WP use in Gaza will damage the main components of eco-systems (air, water, and soil) and some processes may be irreversible. As a result the food chain will be affected due to the damage of biodiversity there. The marine life in Gaza also will be damaged for a long period of time due to the contamination of the sea water by white phosphorus.

Since the beginning of Israel's ground offensive in Gaza on January 3, 2009, there have been numerous media reports about the possible use of white phosphorous by the Israeli military.

It was identified stockpiles of white phosphorus (WP) shells from high-resolution images taken of Israel on the Israeli-Gaza border. The pale blue 155mm rounds are clearly marked with the designation M825A1, an American-made WP munitions.

The rounds, which explode into a shower of burning white streaks, were first identified at the start of Israel's ground offensive.