Ecotoxicology is one of the main applications of the Deheyn Lab’s research on light in nature. For instance, changes in neuro-controlled light production in brittlestars are signs of sub-lethal neuro-toxicity. Our studies of light production in organisms like these can be used to detect toxicity before it kills the organism. This concept of early sign of sub-lethal toxicity detection is also used when monitoring changes in biofluorescence of organisms.