Missing radioactive material is not a new problem
The radioactive material which was either stolen or lost last month in Malaysia is still missing (at the time of writing). The Malaysian incident is just the newest (again at the time of writing) of a series of incidents concerning missing, lost or stolen nuclear material.
Some of these incidents stretch back years., here is one that has come to light recently.
Radioactive material missing since the Cold War
In India, Uttarakhand tourism minister Satpal Maharaj recently expressed concern over radioactive material that has been missing for over 50 years. The material originated in a nuclear-powered spying device, designed to listen in on the Chinese, installed on the summit of Nanda Devi (the second highest mountain in India) in 1965. During the operation, the team from America’s Central Intelligence Agency and India’s Intelligence Bureau were forced off the mountain by a blizzard.
When they returned to the site several months later the spying device, the nuclear-fuelled generator and plutonium capsules (essentially the battery) were missing, presumably flushed down the mountain and buried under snow. Plutonium remains active for many years: the longest-lived is plutonium-244, with a half-life of 80.8 million years, plutonium-242, with a half-life of 373,300 years, and plutonium-239, with a half-life of 24,110 years, the remaining radioactive isotopes have half-lives that are less than 7,000 years. It is not stated in the article but the isotope used could be Plutonium-238 (half-life of 88 years, alpha particles emitter) as it is used as a heat source in radioisotope thermoelectric generators.
The minister is concerned that the atomic device might be polluting the water of the Ganga (Ganges) river, even if this is not the case the item remains a radiological danger sitting on the mountain.
Any missing radioactive material is a cause for concern and shows the need for continued nuclear scanning and vigilance from governments and first responders.
You can read more about the Indian missing plutonium incident here.