The recent U.S.-Israeli airstrikes on oil depots in Iran have caused a wave of concern due to reports of black rain falling over parts of the country. This phenomenon, described as “acid rain,” has raised alarms among Iranian residents who have experienced headaches, breathing difficulties, and oil-contaminated rain settling on buildings and cars. The aftermath of the bombings has left a trail of destruction and environmental hazards that are now becoming apparent.
As an atmospheric chemist and chemical engineer specializing in air pollution research, I am deeply troubled by the implications of this black rain. It is not just acid rain that is falling but a toxic mix of pollutants that pose a significant threat to human health and the environment. The contaminants in the rain include hydrocarbons, ultrafine particles (PM2.5), and carcinogenic compounds like polycyclic aromatic hydrocarbons (PAHs). Additionally, the rain may contain heavy metals and inorganic compounds from the bombed oil depots, further exacerbating the pollution levels.
The smoke generated by the airstrikes also contains sulfur dioxide and nitrogen dioxide, which can lead to the formation of sulfuric acid and nitric acid in the air. These acids contribute to the acidity of the rain, creating a hazardous situation for those exposed to it. While sulfur is typically removed from crude oil during the refining process, the bombings have released significant amounts of sulfur compounds into the atmosphere, leading to the formation of acid rain.
In the short term, exposure to the toxic smoke and black rain can result in immediate health issues such as headaches, respiratory problems, and exacerbated conditions for vulnerable populations. Long-term exposure to these pollutants can increase the risk of cancer, cardiovascular diseases, and other health complications. The pollutants deposited on surfaces by the black rain can also pose a threat when disturbed, re-entering the air and perpetuating the cycle of contamination.
The environmental impact of conflict, as seen in past wars in Iraq and Kuwait, highlights the long-term consequences of such military actions on public health and the ecosystem. Measures to mitigate the effects of the black rain include wearing masks, seeking shelter indoors, and minimizing exposure to polluted surfaces. However, in the chaos of war, these precautions may be challenging to implement effectively.
It is crucial to address the environmental and health risks posed by the black rain in Iran and take proactive steps to protect the population and the ecosystem from further harm. The aftermath of the bombings serves as a stark reminder of the consequences of warfare on the environment and underscores the importance of sustainable and peaceful solutions to global conflicts.

