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Haagen-Smit, Arie Jan (1900 – 1977) Dutch Atmospheric Chemist

Arie Jan Haagen-Smit (1900 1977) Dutch atmospheric chemist

The discoverer of the causes of photochemical smog , Haagen-Smit was one of the founders of atmospheric chemistry, but first made significant contributions to the chemistry of essential oils. Haagen-Smit was born in Utrecht, Holland, in 1900, and graduated from the University of Utrecht. He became head assistant in organic chemistry there and later, served as a lecturer until 1936. He came to the United States as a lecturer in biological chemistry at Harvard, then became associate professor at the California Institute of Technology in Pasadena. He retired as Professor of Biochemistry in 1971, having served as executive officer of the department of biochemistry and director of the plant environment laboratory. Haagen-Smit also contributed to the development of techniques for decreasing nitrogen oxide formation during combustion in electric power plants and autos, and to studies of damage to plants by air pollution .

While early workers on the haze and eye irritation that developed in Los Angeles, California, tried to treat it as identical with the smog (smoke + fog) then prevalent in London, England, Haagen-Smit knew at once it was different. In his reading, Haagen-Smit had encountered a 1930s Swiss patent on a process for introducing random oxygen functions into hydrocarbons by mixing the hydrocarbons with nitrogen dioxide and exposing the mixture to ultraviolet light. He thought this mixture would smell much more like a smoggy day in Los Angeles than would some sort of mixture containing sulfur dioxide ,a major component of London smog. He followed the procedure and found his supposition was correct. Simple analysis showed the mixture now contained ozone , organic peroxides, and several other compounds. These findings showed that the sources of the problems of Los Angeles were petroleum refineries, petrochemical industries, and ubiquitous automobile exhaust.

Haagen-Smit was immediately attacked by critics, who set up laboratories and developed instruments to prove him wrong. Instead the research proved him right, except in minor details.

Haagen-Smit had a long and distinguished career. In addition to his work on the chemistry of essential flower oils and famous findings on smog, he also contributed to the chemistry of plant hormones and plant alkaloids and the chemistry of microorganisms . He was a founding editor of the International Journal of Air Pollution, now known as Atmospheric Environment, one of the leading air pollution research journals. Though he found the work uncongenial, he stayed with it for the first year, then retired to the editorial board, where he served until 1976.

Once it was obvious that he had correctly identified the cause of the Los Angeles smog, he was showered with honors. These included membership in the National Academy of Science, receipt of the Los Angeles County Clean Air Award, the Chambers Award of the Air Pollution Control Association (now the Air and Waste Management Association ), the Hodgkins Medal of the Smithsonian Institution, and the National Medal of Science. In his native Netherlands he was made a Laureate of Labor by the Netherlands Chemical Society, and Knight of the Order of Orange Nassau.

[James P. Lodge Jr. ]



Lodge, J. P. "Obituary: A. J. Haagen-Smit." Nature 267 (1977): 565566.

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