Black Rain in Tehran: Can War Cause Acid Rain? If So, What Are Its Risks? Watch

Residents in Tehran, the capital of Iran, woke up to dark clouds and reports of toxic rainfall after airstrikes targeted oil refineries and storage facilities in the city. The attacks were reportedly carried out by the United States and Israel as part of the ongoing conflict in the region.

Iran's Red Crescent Society warned people that the rainfall could be dangerous and highly acidic, urging citizens to stay indoors. Officials said explosions at oil depots released large amounts of toxic hydrocarbon compounds, sulfur dioxide and nitrogen oxides into the atmosphere.

Authorities also advised residents not to use air conditioners or ventilation systems that draw air from outside, as this could bring harmful particles indoors.

What Is Acid Rain?

Acid rain is a type of precipitation-such as rain, snow, or fog-that contains high levels of acidic chemicals, mainly sulfuric acid and nitric acid.

These acids form when gases like sulfur dioxide and nitrogen oxides are released into the air and react with water vapour, oxygen and other chemicals in the atmosphere.

Normally, rainwater is slightly acidic with a pH level of around 5.6. However, acid rain can have a pH between 4.2 and 4.4, making it much stronger.

Such rainfall can damage the environment by:

1. Weakening trees and crops
2. Contaminating soil and groundwater
3. Corroding buildings, monuments and metal structures

How War Can Cause Acid Rain

Most acid rain around the world is caused by long-term industrial pollution from factories, power plants and vehicle emissions.

However, war-related acid rain forms much faster and can be far more intense.

During military attacks, explosions and fires can release large quantities of harmful gases into the air within a short time. These gases quickly mix with atmospheric moisture and form highly acidic precipitation.

Because it happens suddenly and in a concentrated area, this type of acid rain is often considered a "flash environmental disaster."

What Happens When Oil Depots Explode?

When oil storage facilities or refineries explode, they burn at extremely high temperatures and release huge clouds of smoke and toxic gases.

These explosions release chemicals such as:

• Sulfur dioxide
• Nitrogen oxides
• Toxic hydrocarbons

Once these gases enter the atmosphere, they combine with water vapour and oxygen to create sulfuric and nitric acids.

These acids mix with cloud droplets and eventually fall to the ground as acidic rain. If the rain also contains soot and burnt oil particles, it may appear dark or oily, sometimes called "black rain."

How Missile Strikes Can Trigger Acid Rain

Missile explosions themselves can also contribute to acid rain.

Many rockets and artillery systems release chemical compounds when they explode. These compounds include sulfur and nitrogen-based gases, which are the main ingredients that form acid rain.

In some cases, the environmental impact becomes worse when missiles strike industrial targets such as chemical plants, fuel depots or gas storage facilities. Large fires from these sites release even more pollutants into the atmosphere.

These toxic emissions can spread through the air and later fall back to the ground in the form of acidic rainfall.

Health Risks From Acid Rain

Acid rain can pose serious health risks, especially when people inhale the polluted air that forms it.

Some possible health effects include:

• Breathing problems such as asthma or bronchitis
• Irritation of the eyes, nose and throat
• Lung damage from long exposure to toxic particles

Environmental damage can also occur when acidic rainfall contaminates soil and water sources.

For example:

• Lakes and rivers may become more acidic, harming fish and aquatic life
• Toxic metals in the soil can be released into groundwater
• Plants and crops can be weakened or destroyed

Past Examples of War-Related Acid Rain

Environmental experts have recorded several cases where military conflicts caused acid rain or similar pollution.

Gulf War (1991)

During the Gulf War, retreating Iraqi forces set fire to more than 600 oil wells in Kuwait. The massive fires released large amounts of sulfur dioxide and other pollutants into the air. Acidic smoke clouds spread across the region, affecting countries thousands of kilometres away.

Syrian Conflict (2013-2017)

In Syria, strikes on industrial and chemical facilities released hazardous gases into the atmosphere, contributing to local environmental contamination and acidic rainfall in some areas.

Ukraine War (2022-Present)

Missile strikes on chemical storage facilities and industrial infrastructure in Ukraine have produced toxic gas clouds. In some cases, these emissions created conditions for localized acid rain.

Environmental Concerns Growing

Scientists warn that attacks on energy infrastructure and industrial sites can have long-term environmental consequences.

When large amounts of pollutants are suddenly released into the air, they can affect air quality, soil, water systems and public health.

The reports of toxic rain in Tehran have therefore raised concerns about the environmental cost of modern warfare and the risks faced by civilians living near targeted industrial areas.

As conflicts continue in regions with large oil and chemical facilities, experts say the possibility of "environmental warfare"-where pollution becomes a byproduct of military attacks-may become an increasingly serious global issue.