War is hazardous to your health.

What we know from past conflicts is that war has a serious impact on things like carbon emissions, pollution, toxic water supplies and other environmentally damaging materials. As we watch the war in Ukraine unfold and ponder future conflicts like Taiwan that might involve American troops, we must start thinking more seriously about war and the environment.

Research by Brown University is shedding light on the impact of the wars in Iraq, Afghanistan and other conflict zones, finding that the U.S. military, among others, contributes significantly to climate change, becoming one of the world’s top greenhouse gas emitters through the fighting of battles.

According to Brown’s Watson Institute, air pollution from military vehicles and weaponry has adversely affected public health among civilians in the war zone and U.S. service members. “Heavy military vehicles have raised more dust than usual, particularly in Iraq and Kuwait, and service members’ exposures to inhaled toxins from that dust have correlated with respiratory disorders that often prevent them from continuing to serve and performing everyday activities such as exercise.”

The report examines everything from the destruction of military base garbage in burn pits to the deforestation in Afghanistan to cancer, birth defects and other conditions associated with war-related toxins. “The water supply in the war zones has been contaminated by oil from military vehicles and depleted uranium from ammunition. Along with the degradation of the natural resources in these countries and a radical destruction of forest cover, the animal and bird populations have also been adversely affected.”

Iraqi medical doctors and health researchers have called for more research on war-related environmental pollution as a potential contributor to the country’s poor health conditions and high rates of infections and disease.”

Now think about Russia and Ukraine.

As Ukraine struggles with its counteroffensive against Russia in a brutal war that has raged for 17 months, policymakers are paying close attention to the environmental damage of the war and the potential for Ukraine seeking reparations once the conflict ends. We think of reparations as related to slavery or human rights, but more and more small countries are asking larger nations to pay for the ecological impact of their advanced economies.

Measuring the damage takes effort. Thousands of miles of Ukrainian nature preserves have become endangered conflict zones with rare species lost forever and conservation progress undone. It will be expensive to measure and reverse the process.

Russia’s targeting of Ukraine’s energy grid has been particularly damaging, as oil depots and gas power plants explode, releasing carbon and methane into the air. Reports suggest that ordinary Ukrainians are feeling the impact, forced to rely on dirtier fuels to keep warm.

The Russians dismiss any talk of environmental damage by its invasion of Ukraine as propaganda, but there is good data from European scientists on the impact of the war. A recent report by GHG, a Dutch firm examining the war’s greenhouse gas impact, found that each explosion of a missile or projectile causes pollution of air, water and land with toxic substances, and that Russian bombing of industrial infrastructure in Ukraine has led to uncontrolled chemical releases.

But it is not just Ukrainians who could feel the impact of war on climate. The war is deepening concerns about a Chernobyl-like event if there is an explosion at the Zaporizhzhia nuclear power plant. That could produce radioactive clouds for miles.

Air is a shared commodity. We have seen what fires in Canada can do to Americans, reinforcing the notion that we are all in this together, and many nations are contributing to a major health crisis.

Even nations that don’t agree with one another, like China, Russia and the United States, are willing to have conversations about climate. (Currently, China leads the world in annual atmospheric carbon dioxide emissions, followed by the United States, India, the Russian Federation, and Japan.) China is making transitions to a low-carbon economy by shifting resources and technologies to meet the moment.

Understanding the environmental impact of war and communicating those dangers loudly should push nations toward shared goals of reducing climate destruction. It could be the issue that brings about what I call a “new values alignment” that is both positive and within every nation’s self-interest.

As for Ukraine, it did not invite an ecological disaster. Russia started the war. In addition to support from the West, Russia should share in the costs of re-building Ukraine, including addressing the environmental degradation. That is the price of invading a sovereign nation. Maybe in the future we all will consider climate before using military might.

Tara D. Sonenshine is the Edward R. Murrow Professor of Practice at the Fletcher School of Law and Diplomacy at Tufts University.