Nuclear Weapons Resources

Breathtaking imagery from photographer Daniel Beltrá showcases the range of issues that UCS works on.

This open letter, signed by more than 40 prominent scientific societies and organizations, was delivered to Congress in March 2025.

An archive of preserved federal government documents on environmental justice and scientific issues.

With your help, we made significant strides toward a better future in 2024.

We know the next four years will be a dangerous time for our country and for everyone who cares about a safe, sustainable, and just future.

Essential readings for understanding the world of radiation, radioactive materials, and the threats they pose to human health

This glossary is intended to help advocates navigate the technical language of nuclear weapons and, specifically, radiation and human health outcomes.

Radiation is absorbed by humans in many ways, and can harm the human body in the short and long term.

Radiation is associated with a wide range of adverse health outcomes, including acute radiation sickness, burns, cancer, cardiovascular disease, or even death.

Human-made sources of radiation have increased since the 1940s in the environments people live in and near.

Radioactive materials are elements that spontaneously break apart, or “decay,” into lighter elements over time. Radiation is energy that’s released during that process—and it’s can be dangerous.