Reading the chemical traces of war on the environment

In the villages of southern Lebanon, the damage often shows up as pale, charred ground where orchards once stood. The deeper damage is chemical, and it outlasts the fighting.

Since October 2023, Lebanese authorities and researchers have documented the use of white phosphorus, along with other munitions, across the south. Lebanon’s National Council for Scientific Research counted 175 white phosphorus attacks in the first months alone, igniting fires across more than 600 hectares of farmland. The Israeli military denies using the shells to start fires, stating that smokescreen munitions are not intended for that purpose.

“White phosphorus is a reactive element,” Mireille Sayegh, a chemist who studies conflict-related contamination told The Beiruter. “It ignites on contact with oxygen, which is why it burns so fiercely. In open air it largely oxidizes, so people assume the threat ends when the flames die. That assumption is wrong.”

The problem begins when the material lands somewhere without much oxygen. Researchers at the Conflict and Environment Observatory found that phosphorus buried in soil with low oxygen, or sitting in water, may not fully oxidize and can remain a risk to people and wildlife. Early measurements point to heavy loading. In January 2024, Lebanon’s Ministry of Environment reported phosphorus in samples from bombed areas at about 900 times normal levels. A later round of testing at eight sites found concentrations reaching 40,000 parts per million.

“Plants need phosphorus, but only in balance,” Sayegh stated. “Flood a soil with it and you disrupt how roots absorb other nutrients. Crops struggle. The land looks intact, yet it stops producing.” A United Nations report on Lebanon likewise found that white phosphorus further reduces soil fertility and increases acidity. Rain then carries the contamination onward. “Soil is a slow-moving river,” Sayegh observed. “What sits at the surface migrates downward toward groundwater, and sideways into streams. In the south, people depend on that groundwater.”

Once phosphorus reaches water, biology takes over. Excess phosphorus feeds algae, producing blooms that strip oxygen from the water and can kill fish. High concentrations can bioaccumulate in fish and in birds of prey. “This is the chain that worries me most,” she added. “A pollutant that enters a stream is eaten by small organisms, then fish, then the birds that eat the fish. At each step the concentration climbs. A single strike can become a decades-long ecological problem.”

Metals, rubble and the road back

Phosphorus is only one layer. Explosions disperse metals from shell casings, and the picture grew starker as testing expanded. The Turabna-Janoub monitoring project, reported in May 2026, compared new soil samples from the Nabatieh and Marjayoun districts with historical samples from 2001. It found significant increases in the median concentrations of four weapon-linked heavy metals, with lead up roughly 1.5 times. A separate 2026 study by the American University of Beirut and the Lebanese University detected cadmium and nickel above safety thresholds in bombed areas.

“Heavy metals do not degrade,” Sayegh emphasized. “Organic pollutants can break down over time. A metal like cadmium simply stays, binding to soil particles, entering crops through the roots, and ending up on someone’s table.”

The living landscape has also taken heavy losses. Lebanese state figures for the 2024 war put the damage at about 1,910 hectares of prime farmland, 47,000 olive trees and roughly 1,200 hectares of oak forest. In a region where small family plots make up the bulk of agriculture, that means lost income as well as lost trees. The World Bank estimated environmental damage from October 2023 through late 2024 at $221 million, mainly through degraded natural resources and disrupted solid waste management.

Then came the 2026 war. Lebanon’s Environment Ministry, working with the national research council, described the damage in April 2026 as “ecocide.” Reported estimates put the rubble from bombed buildings at around 16 million tons, and researchers warn it may contain asbestos, heavy metals and phosphorus residues. A ministry assessment found that 78 percent of southern farmers had stopped working, mostly because of displacement.

“Rubble is not inert,” Sayegh cautioned. “Every rainfall leaches something out of it. If nobody manages it, contamination spreads long after the cameras leave.” Recovery will be slow. Sayegh outlined what scientists consider essential. The first step is mapping hot spots, since contamination is patchy rather than uniform, then testing groundwater, treating or removing the worst soil, and replanting. Unexploded ordnance complicates every step.

“We cannot clean what we have not measured, and we cannot measure what we cannot safely reach,” she concluded. “The first task is documentation. The second is giving farmers the means to return.”