The late UC Berkeley professor John Edward Casida (1929-2018), internationally recognized for his work on pesticides and their effects on humans, “was the pesticide toxicologist of his generation, based on his research, his leadership and the impact of the many alumni from his laboratory. With pesticide toxicology as his base, his insight and brilliance illuminated multiple adjunct fields and inspired generations of scientists.”

So wrote two Casida lab alumni, UC Davis distinguished professor Bruce Hammock and Qing X. Li, a professor at the University of Hawaii, Manoa, in their recently published biographical memoir in the Royal Society of Chemistry journal.

Casida, a UC Berkeley professor of toxicology and nutritional science for 50 years, also taught environmental science, policy and management, before becoming an emeritus professor in 2014. However, he continued to do research and mentor students until his death at age 88. He was actively involved with the UC system and often served on exam committees at UC Davis.

Casida was elected a fellow of the National Academy of Sciences in 1991 and to the London- based Royal Society in 1998. He won the first International Award for Research in Pesticide Chemistry in 1971 and the 1978 Spencer Award for Research in Agricultural and Food Chemistry by the American Chemical Society.  In 1993, he was awarded the Wolf Prize in Agriculture "for his pioneering studies on the mode of action of insecticides, design of safer pesticides and contributions to the understanding of nerve and muscle function in insects.”

Hammock, who holds a joint appointment with the Department of Entomology and Nematology and the UC Davis Comprehensive Cancer Center, studied in the Casida lab for four years. Hammock received his doctorate in entomology/toxicology from UC Berkeley in 1973 and also served as a postdoctoral researcher there. Li, who holds a doctorate (1990) from UC Davis, studying with Hammock and James Seiber, completed his postdoctoral training under the guidance of Casida before accepting a position at the University of Hawaii in 1995. 

“John's legacy is his science, and this knowledge fostered subsequent science,” wrote Hammock and Li, longtime collaborators and friends of Casida. “A second legacy is the scientists he mentored in his career and the next generation who grew up with tales of ‘when we were in John's laboratory'. At scientific meetings, there is always a period of informal ‘Casida tales' ranging from practical jokes that extend for decades to stories of John and the charming eccentrics in his laboratory.”

“There is also a uniform awe and respect among his alumni. John set a high standard of ethics as well as work ethic in the field…What drives any of us, and particularly John Casida? Clearly wealth and fame were not important drivers, but there was a competitive spirit. The success of his many alumni brought him pleasure. We are confident John appreciated the tremendous contribution his career made to pesticide toxicology, the environment, human health and agriculture.”

In talking to numerous Casida alumni, the authors concluded “that he did it for the fun of science.”

Casida alumnus Sarjeet Gill, now UC Riverside distinguished professor emeritus, described him “the preeminent toxicologist in the world.”

In their abstract, the authors pointed out that Casida's “research in pesticide toxicology led to more effective agricultural chemicals that are far safer for human and environmental health. He used pesticides as probes for his fundamental studies of metabolism and mode of action, resulting in great insight into biological chemistry and the underlying mechanisms of regulatory biology, ranging from voltage-gated sodium channels, through the ryanodine receptor and calcium regulation, the gamma-aminobutyric acid (GABA)-gated chloride channel, to the nicotinic acetylcholine receptors. These discoveries, among many others, have had a profound impact on pharmacology and toxicology.”

Casida's research career “started with the introduction of DDT into agricultural practice and continued to assist in the development of many pesticides that dominate the market today,” the authors wrote, that he “trained multiple generations of toxicologists who obtained leading positions in government, industry and academics.”

Casida, born Dec. 22, 1929, spent his formative years in Madison, Wis. He received three degrees at the University of Wisconsin: his bachelor's degree in entomology in 1951; his masters in biochemistry in 1952; and a doctorate in entomology and biochemistry in 1954. He joined the faculty at the University of Wisconsin for six years, advancing to full professor, and then accepted a faculty position at UC Berkeley, where he remained active in teaching and research until his death on June 30, 2018.

His wife, Katherine “Kati” Faustine Monson, a well-known artist, died in 2021. Survivors include two sons, Eric of BeRex Corp., Berkeley, and Mark, professor of theoretical chemistry, Grenoble-Alps University, Grenoble, France. Casida “loved laboratory science and this, coupled with insatiable curiosity and a gift for finding the unexpected, led to papers from his laboratory sparkling with creativity,” the authors shared. “He similarly loved teaching at all levels and had just finished grading the final examination in his toxicology class at the time of his passing.”

“The phrase ‘long and productive career' is often used in remembrances, but this phrase is seldom more appropriately applied than when it describes J. E. Casida,” Hammock and Li wrote. “His first lead author paper was published when he was an undergraduate in Science Magazine. John was productive until his last brief illness, and even during this period of hospitalization he was planning his next works.”

Professor Casida is sorely missed by his colleagues and the broad field of toxicology and pharmacology, they said.