Dr. Welch was born in Stoke on Trent on June 28, 1939. He attended school locally before winning an open scholarship to St. Catherine’s College at the University of Cambridge to read Natural Sciences. After graduation in 1961, he went on to the University of London and obtained a Ph.D. in Chemistry in 1965 from Queen Mary College for his studies in recoil reactions of tritium. That year, he moved to the USA for postdoctoral studies at the Brookhaven National Laboratory with Al Wolf, Ph.D. to further pursue his interest in hot atom chemistry. In 1967, Dr. Welch moved to St Louis to accept a faculty position at Washington University working with Dr. Michel Ter-Pogossian; at this point, he turned his attention toward medical applications of radiochemistry, including isotope production. Over the 45 years that Dr. Welch was at Washington University, he became internationally recognized for his contributions to radioisotope preparation, accelerator target chemistry, and radiopharmaceutical chemistry which are reflected in a total of 558 manuscripts, 4 books, and 73 contributed book chapters.
Dr. Welch's contributions to the field went well beyond radiopharmaceutical chemistry, in addition to his exceptional intellect, one of his key skills was the ability to develop longstanding collaborations across a variety of disciplines. Many of these originated during the early days of his career at Washington University. His collaborative interactions gradually moved in wider, more global circles as people’s careers took them to other institutions and organizations. One example of this collaborative effort is his work with John Katzenellenbogen, Ph.D. at the University of Illinois, on radiolabeled estrogens. Dr. Welch's willingness to collaborate outside of the chemistry arena allowed him to see many novel radiopharmaceuticals translate from the laboratory into the clinic.
Dr. Welch was also an early adopter and developer of technologies, and many people who have spent time working with him will remember the enthusiasm with which any new (or prototype) piece of equipment would be received. Through these interests, he was able to identify opportunities. Another important legacy from Dr. Welch was the development of cyclotron produced copper-64 and establishment of the NIH Research Resource to supply such isotopes. This advance, in combination with small animal imaging and even now human imaging, has proven to be very widely used as evidenced by many articles featured in this journal. Through the Research Resource, Dr. Welch made available several “new” imaging isotopes that were heretofore unavailable commercially, spawning a breadth of nuclear imaging research.
During his career, Dr Welch's scientific contributions garnered numerous honors. He won all of the major awards from the Society of Nuclear Medicine, including the Charles de Hevesy Nuclear Medicine Pioneer award and the Benedict Cassen Prize, and he witnessed the creation of a new award named in his honor. His achievements were also recognized by the American Chemical Society, the American College of Radiology, the Radiological Society of North America, the Society of Molecular Imaging, and the Academy of Molecular Imaging. In 1999, he was elected as a member of the Institute of Medicine and worked on numerous advisory panels for the Institute and the National Academy of Sciences. He was one of the founding members of the International Symposium of Radiopharmaceutical Chemistry, the Workshop on Targetry and Target Chemistry and served as the first President of the Society of Radiopharmaceutical Sciences, founded from the biannual symposia. He also served as the President of the Society of Nuclear Medicine from 1984 to 1985.
 McCarthy, Timothy J., & VanBrocklin, Henry F. (June 21, 2012). In Memoriam: Michael John Welch, Ph.D. 1939-2012.