From a laboratory at University College London, a neuroscientist has cast a long shadow over the humble LED bulb, comparing its potential health risks to the slow-burning catastrophe of asbestos. The warning speaks to a recurring anxiety in modern life — that the technologies woven most deeply into our daily routines may carry costs we have not yet learned to measure. Yet the evidence beneath this alarm, a study of just 22 people, reminds us that the distance between a question worth asking and a crisis worth declaring is one of the most consequential gaps in public understanding of science.