VALE Denis J. Hamilton 

Published 9 December 2021 

Written by Pieter Scheelings FRACI CChem

Distinguished pesticide chemist

Denis Hamilton passed away on 5 November in Brisbane after a short illness. He was an Honorary Life Member and Fellow of the RACI as well as a Fellow of IUPAC. He was a well-respected analytical chemist, highly regarded by his Queensland Department of Primary Industries (DPI) colleagues, but it was his outstanding international contributions to pesticide chemistry and associated regulatory systems that distinguished Denis from many of his peers.

Denis grew up on an apple orchard in Cottonvale, on Queensland’s Granite Belt, near his grandparents and extended family. Denis was close to his grandfather, who instilled in Denis a love for woodwork. Later in life, at the Indooroopilly Men’s Shed, Denis often recalled that his grandfather, a bush carpenter, would fix most things on the farm with just a hammer and screwdriver.

Denis excelled at school and was awarded an ‘agriculture’ bursary to board at Ipswich Grammar where he finished as dux in 1959. He also excelled at most school sports, including tennis and rugby. He graduated from the University of Queensland with a BSc and MSc in chemistry. In 1963, he joined Queensland’s Department of Agriculture and Stock (now DPI) as an agricultural chemist, where he advanced to increasingly senior roles including principal scientific advisor before his retirement in 2009.

In 1985, Denis was given responsibility for managing an Australian International Development Assistance Bureau project titled ‘China Agrochemicals’, whereby he began to develop his reputation as an international expert in ‘pesticide chemistry’. His contributions towards the advancement of international regulations regarding acceptable levels of pesticide residues in food and feeds was significant and highly regarded. He represented Australia on the Collaborative International Pesticide Analytical Council and was involved in a number of WHO/FAO committees, including the Codex Committee on Pesticide Residues (CCPR), the Joint Meeting on Pesticide Residues and the Joint Meeting on Pesticide Specifications. The latter two are independent expert groups formed to provide advice and recommendations to CCPR and FAO/WHO. Both expert groups benefited from Denis’s chairmanship for several years.

For a decade, Denis represented the states and territories on Australia’s delegation to CCPR, which is responsible for the establishment of international standards (maximum residue limits) for pesticide residues in foods and feeds. Due to his knowledge and expertise, Denis substantially raised the profile and status of Australia within CCPR and the Codex Alimentarius Commission.

Denis was a member of the editorial board of Pest Management Science and the international advisory board for Outlooks on Pest Management. He edited or co-edited numerous international publications on pesticide residues and safety assessment of pesticide residues in food and drinking water. Denis was also a member of the IUPAC Committee on Crop Protection Chemistry, where he led projects dealing with pesticide residues in food and water, which resulted in significant, influential publications. In recognition of this work, Denis was the recipient of the inaugural IUPAC International Award for Advances in Harmonised Approaches to Crop Protection Chemistry in 2010. Notwithstanding his formal retirement in 2009, Denis continued with his interest in pesticide chemistry, writing and reviewing scientific papers and consulting with Australian and international colleagues, many of whom continued to seek his advice. 

Denis had a close and loving relationship with his family, including his wife Gloria, daughter Karen and grandchildren Stuart, Julia and Holly, on whom he doted.

I knew Denis by reputation but I only met him personally after his retirement at RACI retired chemists outings and the Indooroopilly Men’s Shed where he continued with his woodworking hobby making native bee hotels with his favourite bamboo timber, which he cultivated at home. He retained all copies of Chemistry in Australia since his membership commenced in 1962 – all carefully bound with bamboo and fishing line. He was an active participant and contributor to the Men’s Shed book club and the ‘current affairs’ discussion groups. He had a passion for historical books and frequenting the annual secondhand book fairs; he would often come to Men’s Shed discussion groups with a last century book to confirm that today’s global problems were often a revisit on yesteryear’s issues from which society still hadn’t learned.

I would like to acknowledge the input from many of his past and present friends and colleagues in summarising Denis’s distinguished career, his positive influence on the career development of younger scientists and his contributions to harmonising standards for pesticide residues in food. In recognition of his many colleagues worldwide and in testament to his national and international reputation, his funeral service was livestreamed nationally and to 15 other countries.