Thomas Loy obtained a BSc in Geography from Redlands University, Arizona in 1970, while simultaneously working with the US Geological Survey in Alaska. In 1972 he received an MA from the University of British Columbia, and in the same year became director of the Glenrose Cannery Site Project. Between 1973 and 1987, Loy was a curator of archaeological collections at the Royal BC Museum. While in this post, he developed the study of residue analysis, investigating traces of human organic material on items. In 1987, he joined the faculty of Australian National University in Canberra, where he remained until 1995, when he moved to the University of Queensland. In 1991, Loy was invited to analyze residue on the tools and clothing of the prehistoric Austrian ice mummy nicknamed Ötzi.