Dioxins are implicated in The Seveso disaster in Italy and the lingering disputes about deformities and birth defects caused by the use of the Agent Orange defoliant in the Vietnam war (Wikipedia summary). They are often described as the most toxic chemicals known to man (example, another example).

Not everyone agrees (see this paper). And prominent people have survived poisoning with them such as former Ukrainian president Viktor Yushchenko.

So do dioxins deserve their public image as one of the worst toxins?