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Grinnellians you should know (or know about): Clair Patterson ’43

Topics/tags: Grinnellians, science

As someone who loves Grinnell and the people who inhabit or have inhabited its confines, I consider it my responsibility to introduce folks to other Grinnellians they may not know. In the past, I’ve written about historical Grinnellians, like Hallie Flanagan 1911 or Grant Gale, and current Grinnellians, like Erik Simpson.

Recently, I learned about a Grinnellian I should have known about, but did not. I am thankful to Mitch Erickson ’72 for telling me about Clair Patterson ’43. Patterson earned an A.B. [1] in Chemistry from Grinnell, a Master’s degree from Iowa, and a Ph.D. from the University of Chicago.

Afterwards, one of Patterson’s first major accomplishments was to determine the age of the earth. As I understand it, he did so looking at lead isotope data from iron meteorites. And, as far as I can tell, his estimate of 4.55 billion years has stood the test of time [3], give or take a few million years. I appreciate what his biographer, George R. Tilton says that Patterson said after the discovery,

True scientific discovery renders the brain incapable at such moments of shouting vigorously to the world Look at what I’ve done! Now I will reap the benefits of recognition and wealth. Instead such discovery instinctively forces the brain to thunder We [4] did it in a voice no one else can hear, within its sacred, but lonely, chapel of scientific thought. [5]

In studying lead, Patterson came to discover that our industrial processes were adding significantly to the amount of lead in the environment, and that the additional lead was a risk to human beings. By the mid-1960’s, he was pushing for a change in lead usage and being heavily criticized for his perspectives. He pushed for improvement on controls on lead in the air, in food, and in gasoline. He participated in a 1978 National Research Council panel on lead that expressed concerns. However, he did not consider that enough. Tells us that,

In his lengthy 78-page minority report Patterson argued that the majority report was not forceful enough. Basically he said that the dangers of the prevalent practices were already clearly enough defined and that efforts should start immediately to drastically reduce or completely remove industrial lead from the everyday environment. That included gasoline, food containers, foils, paint, and glazes. He also cited water distribution systems. He urged investigations into biochemical perturbations within cells caused by lead exposures ranging down from typical to 1/1000 of typical. He had long criticized assigning a sharp limit for lead in air or blood to denote a dividing line between poisonous and non-poisonous levels.

While Patterson was not the only voice to call for lead reduction, he was undoubedly one of the most distinguished scientists to do so, and he took a clear lead in these matters, drawing deeply on his scholarship. In doing so, he exemplifies our goal of preparing students who are prepared in life and work to use their knowledge and their abilities to serve the common good [6,7].

Postscript: The more I think about Patterson, the more impressed I am. Just imagine what it must be like to know that you computed the age of the earth and that that’s not the most important work you’ve done.

Postscript: I’m surprised to see that there seem to be two spellings of Patterson’s first name. His biographical memoir from the National Academy of Sciences lists him as Clair Cameron Patterson, as does his Wikipedia page. However, his paper on the age of the earth lists him as Claire Patterson (note the added e), as does The Des Moines Register.

Postscript: I’m happy to see that a few months after I wrote this musing, The Grinnell Magazine published a nice piece on Patterson written by Michele Regenold ’89 and illustrated by Kevin Cannon ’02. I take no credit for the piece; I assume that they were also inspored by Erickson.

[1] It makes me happy to know that Grinnell used to use the Latin ordering for academic degrees (artium baccalaureus, I believe). It’s what Chicago used when I was there [2].

[2] That is, I have an S.B. and an S.M. in addition to my Ph.D.

[3] Well, a bit more than a half century, comparatively little with regards to his estimate.

[4] Tilton tells us that

we refers to what Patterson calls the generations-old community of scientific minds.

[5] Tilton, George R. 1998. Clair Cameron Patterson. In National Academy of Sciences of the United States of America, Biographical Memoirs: Volume 74, pp. 267–288. Washington, DC: National Academy Press. Available online at

[6] Grinnell College, Mission Statement. Available online at

[7] Of course, Grinnell [8] likely had a different mission statement in 1943.

[8] Iowa College?

Version 1.0 of 2018-10-19.

Version 1.1 of 2019-07-31.