Arktis detectors can also be installed in doorways or used in baggage handling locations. They work completely passively but are different from Geiger counters, the best-known radiation detectors. Special material in Arktis’ devices reacts when exposed to the subatomic particles emitted by radioactive materials. This reaction produces a small amount of light – scintillation – which is measured by sensors and then processed by computer algorithms.
Because different radioactive substances cause different light emissions, it is often possible to see immediately what kind of material has been detected, for example an isotope of uranium or cobalt. Panniello explains that his company can integrate notifications into security systems so that employees receive automatic alerts on their smartphones when radioactivity is found nearby. Detections can also be signaled at central security hubs, where an appropriate response can be coordinated.
His company also makes a drone equipped with a radiation sensor. That’s not very useful at airports, but it can help researchers scan a large area to locate discarded radioactive material.
From smoke detectors to industrial meters to medical teletherapy devices, there are many examples of objects and devices containing radioactive material. Not all of them pose a risk of harm, but some do. And there is concern that some landfills or heaps have been contaminated by people carelessly disposing of more dangerous sources of radioactivity.
A report published last year by Zenobia Homan, of King’s College London, and colleagues highlighted the challenges some South Asian countries face, such as ensuring the careful disposal of radioactive materials. “There are people who specifically hunt this, they might try to steal it, or smuggle it to sell the material,” she says. In May 2021, investigators discovered a scrap dealer in India who reportedly collected 7 kg of uranium. Officials arrested two men who allegedly tried to sell the uranium online.
When radioactive matter is improperly disposed of and later discovered this way, the consequences can be horrifying. Take the accident in Goiânia. In 1987, two men in Brazil stole parts of a teletherapy device from an abandoned radiotherapy institute in the city of Goiânia. They almost immediately developed radiation sickness and experienced vomiting and diarrhea, among other things, but proceeded to dismantle the machine, which unbeknownst to them contained the highly radioactive isotope caesium-137. A few days later, they sold some parts of the machine to a scrap yard.
The scrap yard owner found a glowing blue powder in one of these parts, which he and his relatives extracted and handled, completely unaware of the dangers. His 6-year-old niece, Leide das Neves Ferreira, even played with the powder and painted it on her face. She and three other people died as a result of radiation exposure. About 250 people were infected in the incident.
There are other similarly bizarre and tragic examples. In Kramatorsk, Ukraine, cesium-137 was lost from a measuring device in a quarry in concrete and then in the wall of an apartment building. Successive residents were exposed to radiation in the 1980s as a result. At least two children died before the source was discovered.
Given that there are many sources of radiation, of varying strengths, in the wild, constant vigilance is required. Last month, the International Atomic Energy Agency published a report on the theft of a teletherapy device in Mexico in 2013. The device contained cobalt-60 and was removed from its shield before being abandoned in a field. A member of the public who found the machine suffered radiation injuries to their left shoulder and right leg.
Both Homan and Ghiassee say international regulations and monitoring protocols for radioactive materials have improved tremendously over time, especially at country borders, resulting in discoveries like the one at Heathrow in December. Yet there are still gaps in this defense. Certain countries don’t have the capabilities to detect the movement of radioactive and nuclear material across borders, Ghiassee says.
Panniello says some countries should be more proactive in screening for radioactivity at airports. “The UK is one of those countries where there’s the right amount of attention to those things,” he says. “But it’s an exception.”
