[1] He was a member of the faculty of Chemical Engineering and Applied Chemistry at the University of Toronto and the founding director of the Canadian Environmental Modelling Centre at Trent University.
[2] He has stressed that principles of good practice also need to be adopted for chemical assessments, especially in a regulatory context.
[3] In 2004, Mackay was invested as an Officer of the Order of Canada for having "greatly contributed to the quality and our stewardship of the global environment".
[4] In 2004, he was also invested into the Order of Ontario for "his outstanding contributions to environmental science".
[5] Mackay died at the Peterborough Regional Health Centre on 20 October 2023, at the age of 86.