Dr. Plaa is a pioneer in the use of dose-effect relationships to quantitatively compare hepatotoxicants, using both biochemical and morphological indices of liver injury. He has published more than 225 research articles, edited five books, written 35 chapters in other books, and authored 10 major scientific review articles.

At the time of his retirement in 1995, Dr. Plaa was Director of the Interuniversity Center for Research in Toxicology at the Universite de Montreal. A year later, he was named Professor Emeritus for his outstanding contributions to the institution and his scientific discipline during his academic career. He received a starter grant from the Foundation when he first moved to Canada in 1968 that enabled him to initiate his research activities in that country.

Dr. Plaa has served on many national scientific and expert committees in Canada and the U.S. He has received 14 major awards for his achievements, including the Merit Award of the Society of Toxicology in the U.S. and the Award of Distinction of the Society of Toxicology of Canada.