Dr. Thomas C. Sparks

Dr. Thomas C. Sparks.

By some estimates, there are more than a million insect species in this world. Only a small percentage of this number is detrimental to the quality of our lives, but these are the species that drive research by scientists like Dr. Thomas C. Sparks, R&D Magazine’s 44th Scientist of the Year. The entomologist’s job is to know these insects, even down to the molecular level, to discover ways to keep them from destroying a very precious commodity: our food.

Most of us take for granted the quantity and quality of the food we eat. It wasn’t always this way. Before the advent of industrial fertilization and pest control, growing enough food to eat could be a problem. Now, with more than 6 billion people to feed worldwide, careful management of agricultural resources is a requirement.

Sparks didn’t always have to view insects as a pest, however. In fact, his early research in entomology focused on beneficial insects, not the pests he would later have to contend with. He grew up in the lush Central Valley region of California, where fresh, quality food was always in healthy supply and there were plenty of insects around. What he learned about food and nature led him to chemistry coursework in college in the 1970s. But another interest, biology, took hold and he became a quick study on all things about insects. Sparks earned his bachelor’s degree in biology at California State Univ., Fresno, and his doctorate in entomology, toxicology and physiology at the Univ. of California, Riverside, in the well-known laboratory of Dr. Bruce Hammock, where he completed key research on hormones that would guide him into the unexplored regions of entomological science.

From his work in California, Sparks immediately moved into a teaching position in the Dept. of Entomology at Louisiana State Univ. He reportedly moving from assistant to full professor in record time and was well-respected for his teaching ability. His toxicology course, in particular, was considered top-notch. In academia, he continued pioneering research on juvenile hormone esterase, an enzyme critical to the regulation insect development and a target for agrochemicals. Others studied this hormone before him, but his work was among the most important, helping spawn nearly 500 scientific papers on this topic.

An extended professorship, however, was not Sparks’ fate. Interested in new ideas in insect research and eager to satisfy his instinct to invent, he joined Dow AgroSciences. With Dow, he was able to take advantage of the strong collaboration between chemists and biologists and begin his groundbreaking work in insecticide development. The focus of his efforts was to develop the recently discovered class of large molecules called spinosyns. This fermentation-based chemistry has rapidly transformed the insect control industry thanks to an unprecedented ability to control agricultural and medical pests without the environmental and human impact normally associated with such products. Sparks did not discover this chemistry, but his ability to perfect spinosad chemistries through key advancements in the field of quantitative structure activity relationships and refine new products based on this technology has earned him recognition as one of the fathers of this new approach to insect control. He formed the Macrolide Research Group that coordinated spinosad-related R&D at Eli Lilly and Dow for several years and which has produced numerous successful products.

In what may soon become Sparks’ most important achievement so far, he has advanced this field by resolving a previously intractable molecular problem through the computational discipline of artificial neural networks. The problem was this: computer-aided modeling and design tools which had guided prior spinosyn development had run up against a wall. The molecules had become simply too complex to design using linear methods. He hit upon a solution during a discussion with a friend who was designing a robotic vacuum cleaner that was able to “learn” from its surroundings by using programming constructs that mimic the properties of biological neurons. Inexpensive artificial neural network programs were available, but they had never been used to help develop synthetic molecules.

Sparks, who was at UC Riverside during the silicon revolution and knew the potential of advanced computing tools, put one such program, Braincel, to work on an advanced spinosyn problem, asking small questions about minute changes in molecular structure. By identifying advantageous patterns in the answers, he was able to build a new chemistry, spinetoram, which represents one of the most advanced insecticides to reach the market. Derived through the fermentation of a natural soil organism followed by chemical modification, it impacts the environment in the same way a biological product, yet operates with the efficacy of a synthetic technology. Registered with the EPA’s Reduced Risk Pesticide Initiative, spinetoram can be used in a variety of crops, at low rates, and with minimal impact on mammals or beneficial insects. Some estimates claim that spinetoram will eliminate 1.8 million pounds of organophosphate pesticides used in tree nut and fruit crops in just the first five years of use. Without the efforts of Sparks and his team, this chemistry would have been far more elusive.

A 30-year member of the Entomological Society of America and the American Chemical Society, Sparks has been recognized with numerous accolades, including a Merck Research Development Award, several Dow Chemical awards, an Entomological Society of America Outstanding Graduate Student Award, a National Institutes of Health postdoctoral fellowship, an Arthur E. Schwarting Award for Best Paper in 2006, and the 2008 EPA Green Chemistry Award. He has also been successful on the intellectual property front, with several patents or patents pending. His reputation as a teacher is reflected in his nearly 100 invited lectures worldwide and a great many chemists who are now conducting research with the tools and methods Sparks has pioneered. After more than 130 published articles and breakthroughs in cheminformatics, insect endocrinology, insect biogenic amines, and high throughput screening, Sparks continues his mission of discovery. He was recently promoted to Advisor at Dow AgroSciences, a position reserved for only a few scientists who have distinguished themselves by making significant contributions to both science and The Dow Chemical Company.