The story concept
A kitchen scanner flashes and toy-sized hazmat characters rush toward a banana. The alarm, tiny squad and glass dot diagram are inventions for the story. The diagram is conceptual and not to scale; it is not a test result.
What the source actually says
The US Environmental Protection Agency explains that bananas contain potassium and a small fraction of potassium is naturally radioactive. The agency estimates that eating one banana delivers a very small radiation dose, about 0.1 microsievert.
Where the evidence stops
Natural radioactivity does not make an ordinary banana a radiation hazard. The EPA says foods with these small amounts do not pose a radiation risk. The cartoon scanner is not a real measurement, and the dot count does not represent the actual fraction of potassium-40.
The useful takeaway
A banana is technically a little radioactive because of naturally occurring potassium-40. The amount is tiny. You can treat it as a normal snack without a hazmat suit.
Curious about the opposite twist? Microwaving food does not make it radioactive ↗