Manmade trace radiation is being found all over Europe and theories abound as to why. Accusations include Russian plots and ask what the government might be hiding. But the explanation is far less exciting, as it often is.

The French Radioprotection and Nuclear Safety Institute (IRSN) said last week that a radionuclide called Iodine-131 was being found in trace amounts across Europe, first in northern Norway, then in Finland, Poland, the Czech Republic, Germany, France and Spain.

Suggestions of a Russian plot were given credence by the location of the first discovery: Northern Norway shares a border with Russia. Could it be a secret nuclear test right at Europe's northern doorway?

Well, no.

Jayde Lovell, scientist and host of SciQ told IBTimes UK that the most likely explanation was simply Europe's abundance of nuclear reactors - the ones that make electricity - although trace radiation is not usually detectable.

"Iodine 131 is not a mystery," Lovell said. "It's released in low levels normally as part of nuclear power and since nuclear power is common throughout Europe it's not unusual to be able to detect trace amounts during certain types of weather, particularly the cold weather of a European winter."

So not a secret Russian nuclear test? "I would be expecting to see a lot more and more different kinds of radiation than just iodine 131 if it was a nuclear test. It would be incredibly abnormal to be able to detect iodine 131 in these amounts from a Russian nuclear test," she explained.

"It's also not dangerous and not even close to levels that a human might experience undergoing a nuclear imaging technique.

"It is far more likely that this trace amount, which is extremely safe, is from one of the many nuclear reactors in Europe and is not abnormal or a sign of a leak - and is not caused by a nuclear weapon of any kind that I would know of."