occur." Using these techniques, Quastel was able to quantify the influence of various plant hormones, inhibitors and other chemicals on the activity of microorganisms in the soil and assess their direct impact on plant growth. While the full work of the unit remained secret, certain discoveries were developed for commercial use after the war. Best known is the compound commonly labeled as 2,4-D, one of the first systemic or hormone herbicides, a class of chemicals responsible for triggering a worldwide revolution in agricultural output and still the most widely used weed-killer in the world. Another invention was developed as a soil conditioner and is marketed by Monsanto Company under the trade name Krilium. After World War II, Quastel was invited to become Assistant Director of the newly founded McGill University-Montreal General Hospital Research Institute and professor of biochemistry at McGill University, and, in 1947, he accepted the invitation. The following year, he was appointed Director of the Institute. During his nineteen years at McGill University, Quastel supervised seventy Ph.D. candidates and his Institute published over three hundred scientific papers on topics including metabolism of micro-organisms, soil biochemistry, neurobiochemistry, neurotropic drugs, anaesthesia, cancer biochemistry, enzyme inhibition, and transport of nutrients and ions across membranes. Once he reached McGill's retirement age in 1966, Quastel accepted a professorship of neurochemistry at the University of British Columbia in the Department of Psychiatry, the first such position for that institution. Quastel received many honors, including, in 1970, Canada's highest recognition, the Companionship of the Order of Canada. In the same year, he received an honorary doctorate from the Hebrew University in Jerusalem, of which he had also been a governor since 1950. He received an honorary Doctorate of Science from McGill University in 1969. He was made an honorary Fellow of the Royal Society of Edinburgh in 1983. He died in Vancouver on 16 October 1987. Family In 1931 Quastel married Henrietta Jungmann and they had three children—Michael, David and Barbara. Following her death in 1973 he married again in 1975 to Susan Ricardo. He had eleven grandchildren including mathematician Jeremy Quastel. Publications Chemistry of the Brain (1937) The Mechanism of Enzyme Action (1940) The Influence of Biochemistry in Modern Life (1956) The Chemistry of Brain Metabolism in Health and Disease (1961) Metabolic Inhibitors (1973) References Further reading Royal Society citation 1899 births 1987 deaths Alumni of Imperial College London Alumni of Trinity College, Cambridge