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(212) 854-6580 April 30, 1999



Charles Dawson, Columbia Chemist

Known for Work on Poison Ivy, 88


Charles R. Dawson, professor of chemistry at Columbia University for 40 years and discoverer of the toxic compounds in poison ivy, died Wednesday (April 28) at Huggins Hospital in Wolfeboro, N.H. He was 88 years old.

He had been diagnosed with prostate cancer several months ago and succumbed to the disease, said his son, John Dawson, a professor of chemistry at the University of South Carolina.

Though he became well known for his work to find a treatment for poison ivy, he was also a dedicated and thorough teacher who taught biochemistry and organic chemistry to generations of pre-medical students as well as to graduate students. He received the Great Teacher Award from Columbia‚s Society of Older Graduates in 1961 and the Mark Van Doren Award for excellence in teaching from the students of Columbia College in 1978. More than 100 graduate students and postdoctoral researchers worked in his laboratory, of whom 50 earned Ph.D. degrees under his supervision.

„The teaching was what really excited him,š said his son, John, who graduated from Columbia College in 1972. „I took classes from him as an undergraduate, and he would rewrite his lecture notes every single time he taught. There were notebooks after notebooks after notebooks. We once calculated that he taught about 10,000 students over 40 years, and many of those students are now doctors all over the country.š

His field of research was the biochemistry of plants. He studied the role in

nutrition and heredity of trace metals near iron in the periodic table of the elements ų manganese, cobalt, nickel, copper and zinc. He focused on copper oxidase enzymes, which are required for the biosynthesis of the red and blue anthocyanin pigments found in flowers and fall leaves, as well as for biological processes in humans. Professor Dawson also developed methods of isolating and characterizing ascorbic acid, or vitamin C.

He was best known for his investigations into naturally-occurring alkyl phenols, such as are found in poison ivy and related plants. Professor Dawson isolated the four active compounds in poison ivy, which previously had been thought to be a single substance, called urishiol. The least toxic of the four was an alkyl catechol, and, with researchers from the National Institutes of Health, he pursued the goal of finding a treatment or vaccine based on the less toxic compound. In 1956, they announced a vaccine, pentadecylcatechol, or PDC, that was effective over a period of weeks or months.

„For the average person, poison ivy is a nuisance,š John Dawson said. „But there are people who are exceptionally allergic to poison ivy, and those were the people my father was trying to help.š

He received honorary doctorates from both his alma maters, the University of New Hampshire in 1953 and Columbia in 1988. Professor Dawson was elected a Fellow of the American Association for the Advancement of Science in 1964 and chairman of the New York section of the American Chemical Society in 1967-68. He contributed 120 research articles to scholarly journals.

Charles Reginald Dawson was born in Peterboro, N.H., April 9, 1911. He earned the B.S. degree in 1933 and the M.S. in chemistry in 1935, both at the University of New Hampshire. He completed his Ph.D. at Columbia in 1938 and spent the following year as a post-doctoral researcher at Cambridge University, as the Cutting Fellow.

He joined the Department of Chemistry as an instructor in 1938, was named full professor in 1952 and professor emeritus in 1979. He was an active member of the Columbia community: elected to the University Senate by the faculty of Columbia College 1955-58; assistant to the dean of Columbia College, 1944-55; Columbia‚s representative on the Board of Managers of the New York Botanical Garden, 1962-79; president of the Columbia Men‚s Faculty Club 1959-60,

and recipient of the Harold C. Urey Award of the Columbia chapter of Phi Lambda Upsilon, the national chemistry honors society. He served on the President‚s Advisory Committee on Athletics at Columbia and was for many

years chairman of the Academic Eligibility Committee for student athletes. In 1979, he was named an honorary member of the Columbia Varsity C Club.

He lived from 1948 to 1979 in Leonia, N.J., with his wife, Dorothea Lockard Dawson. They were married for 61 years and raised three children. He served on the Board of Education of Leonia, 1954-60, and was president of the board in his last two years of service. He received the Distinguished Citizen Award, bestowed by Leonia, in 1967. On his retirement, he and his wife moved to Wolfeboro.

In addition to his wife, of Wolfeboro, and son, John, of Columbia, S.C., he is survived by a sister, Ruth Taylor, Boise, Idaho; a brother, Robert, Leeds, Maine; a daughter, Patricia Dawson Runner, Tiverton, R.I., and seven grandchildren. Another daughter, Sally Dawson Merchant, Reading, Mass., died in 1989.

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