Dioxin toxicity research. Researcher handling a rat during tests on the toxicity and metabolic fate of dioxin compounds when fed to animals. Dioxins are a family of toxic by-products of a number of industrial processes, including burning waste, heating metals and bleaching paper and textiles. They have no industrial use themselves. They are persistent organic pollutants (POPs) and build up over time in living tissue (bioaccumulation). Long-term high-level exposure can cause birth defects, cancer and a higher risk of diabetes.