Tribute to Dr. Ed O. Bennett

Tribology & Lubrication Technology, Oct 2004 by Passman, Frederick J, Jurtshuk, Peter Jr, Malone, Robert W

Following a career that spanned 40 years, this tribology was hailed by many as the of lubricant fluid microbiology.

Editor's note: TLT ran an obituary on Ed Bennett in our February issue, listing his numerous achievements in tribology and his inclusion in such publications as Who's Who in the World; Who's Who in America; Who's Who in the Southwest; National Register of Prominent Americans and International Notables; American Men of Science Leaders in American Science; and Men of Achievement. The authors of this article knew Bennett and wish to add their thoughts to his remarkable career.

In 1991, when Ed Bennett retired from the University of Houston after serving as a faculty member in the Biology Department for 40 years, he repaired to the LaGrange, Texas, farm he shared with his wife, Dorothy, and withdrew from all participation in STLE. Thus, the man whom professor Harold Rossmoore once described as "the founder... of metalworking fluid microbiology1" slipped from the consciousness of many members of our society. Sadly, Harold, another tribology legend, is no longer with us either, making this the second time in less than a year that we find ourselves writing a memorial article about the life and contributions of a colleague, friend and mentor2.

Ed Bennett was born in St. Louis, Mo., on March 16, 1926. After graduating from Kemper Military (High) School in Boonville, Mo., in 1944, Ed joined the U.S. Air Force Medical Corps. After he left the military, Ed matriculated at Lamar College in Beaumont, Texas, from which he received his associate of arts degree in 1947. That year he also married Dorothy McDonald, who would remain his wife and soul mate until her death in May 2003.

After graduating from Lamar College, Ed matriculated at the University of Houston; where he earned a bachelor's of science degree in 1949. Ed then pursued graduate studies at Iowa State University Medical School, receiving a master's of science degree in bacteriology in 1951. He later returned to Houston for his doctoral studies in microbiology at the Baylor College of Medicine, Texas Medical Center.

Ed had served as a teaching assistant during his last year as an undergraduate student at the University of Houston. In 1951, after matriculating at Baylor College of Medicine, he received an appointment as an assistant professor and taught microbiology courses in the University of Houston's Biology Department.

During his tenure as a doctoral candidate and assistant professor, Ed first became involved with his studies in lubricant microbiology. Shell Research had contacted Ed and asked him to investigate the causes of lubricant rancidity. This work culminated in Ed's first metalworking fluid microbiology paper, co-authored with H.O. Wheeler: Bacterial Survival in Cutting Oil (1) in 1954.

Ed received his doctorate and was promoted to assistant professor in 1958. By this time he had published seven more papers on metalworking fluid microbiology. The articles he wrote during these seminal years set the tone for his research focus for the next 33 years.

Ed was particularly interested in two issues: health effects of the microbes that grew in metalworking fluids and the effects of metalworking fluid chemistry on microbe proliferation. By the mid-1950s Ed had developed a simple but reasonably predictive procedure for testing the ability of metalworking fluid formulations to support microbe proliferation.

Through the course of the following three decades, Ed and his students screened thousands of fluids and additives for their antimicrobial activity or ability to suppress proliferation3. Much of this work was published only in Ed's monthly subscriber newsletter, although a small portion was also published in peer-reviewed journals (2, 3 & 4).

Ed was the first investigator to report on the antimicrobial properties of a number of microbicides most commonly used in metalworking fluids today. His researches on microbicide performance led to two fundamental principles of microbicide activity.

First, he demonstrated no single product worked universally. Nearly all of the chemicals he tested demonstrated a similar performance pattern: excellent antimicrobial properties in some formulations, no apparent effect in others, and growth stimulation in third subset of formulations. Some of the chemicals that his team evaluated seemed to be effective in only a single coolant. Not surprisingly, those that were effective in a broad range of formulations became widely used throughout the industry.

Ed's second fundamental teaching was that, at low doses, microbicides could stimulate growth. Ed was wont to illustrate this phenomenon (after offering the judicious caveat, "don't try this at home") citing the practice of feeding a bit of strychnine to older stallions to induce a phenomenon not dissimilar to that offered by a variety of currently available erectile dysfunction drugs. Apparently, a low dose of this very potent poison would make the stallions frisky. A bit too much would do them in.