The cited Wikipedia article cites Baron, Gowda and Kunreuther (1993) and Viscusi, Magat and Huber (1987) as early studies documenting the effect, and an economics study by Kunreuther (1991), but does not state in what year the bias itself was first named or described, and the 1987 study title does not use the term.
What would resolve this A citable source naming the specific year or publication where the term zero-risk bias was first coined.
OpenWikipedia: Zero-risk bias