On the morning of July 16, 1945, the world changed in many ways. The detonation of the world’s first atomic bomb at the Trinity Test Site in New Mexico represented the beginning of a new era in global politics. The start of the Atomic Age also heralded the beginning of the Cold War, and the huge shifts in geopolitics, warfare, economics, and industry that came with it.
But there are many, many other more subtle effects brought about, specifically by nuclear testing. Between 1945 and 1963, when the United States and the Soviet Union signed the Partial Nuclear Test Ban Treaty (PNTBT), thousands of nuclear bombs were tested, scattering radiation around the world. For the most part, this radiation was only in areas where nuclear testing was taking place, in particularly uninhabited areas. That doesn’t mean that it didn’t affect thousands of people, though. As of June 2022, the US government has awarded $2.5 billion to more than 39,000 people affected by radiation through the Radiation Exposure Compensation Act (passed in 1990). We did lots of silly things in those early days, because we did not understand the dangers of radiation. This includes things like sending people to go stand underneath a high-altitude detonation.
Despite limiting (the majority of) our testing to uninhabited areas, it’s not like these places were completely isolated from the rest of the world. These tests put chemical isotopes into the Earth’s atmosphere that had never been there before. In particular, Plutonium 239, Strontium-90, Caesium-137, and Technetium-99 are all byproducts of nuclear fission, but do not occur naturally in our atmosphere. While the concentrations of these elements is so low you don’t need to be concerned, it does cause some problems for specific high-precision detectors.
The production of steel involves blowing oxygen into carbon-rich molten iron in order to reduce the ratio of carbon and turn it into steel. However, the use of atmospheric oxygen means that small quantities of radionuclides are also carried into the steel. Unfortunately, this means that your steel now carries with it a low level of radioactivity. If you then use that steel to make something like, say, a Geiger counter, its measurements will be contaminated by its own radioactivity.
As a result, steel produced before 1945 is more valuable than newer steel. And one of the places you can get such steel? Shipwrecks. Old battleships, sunk to the bottom of the ocean, were produced well before any radioactive contamination, and have been isolated on the bottom of the sea. Jurisdiction is difficult, as the vessels are still technically owned by the nations which sailed them, but they lie in other countries’ territorial waters. However, quite a few World War II shipwrecks have been plundered for their low-background steel.
Thankfully, atmospheric radiation levels have dropped significantly with the implementation of atmospheric test bans like the Partial Nuclear Test Ban Treaty. With governments no longer performing above-ground nuclear tests, atmospheric radiation has almost reached pre-atomic levels. However, we still produce small amounts of isotopes, such as Cobalt-60, from our nuclear reactors. Therefore, this low-background steel will continue to be more valuable than modern steel.