Editing Svante Arrhenius (section)

===Later years===
[[File:Arrhenius family grave.jpg|thumb|Arrhenius family grave in [[Uppsala]]]]
Eventually, Arrhenius's theories became generally accepted and he turned to other scientific topics. In 1902, he began to investigate [[physiology|physiological]] problems in terms of chemical theory. He determined that reactions in living organisms and in the test tube followed the same laws.

In 1904, he delivered at the [[University of California]] a course of lectures, the object of which was to illustrate the application of the methods of physical chemistry to the study of the theory of [[toxins]] and [[antitoxins]], and which were published in 1907 under the title ''Immunochemistry''.{{sfn|Chisholm|1911}}<ref>{{cite book|url=https://archive.org/details/cu31924000273718|title=Immunochemistry; the application of the principles of physical chemistry to the study of the biological antibodies|date=1907|author=Svante Arrhenius|publisher=The Macmillan Company}}</ref>
He also turned his attention to [[geology]] (the origin of [[ice age]]s), [[astronomy]], [[physical cosmology]], and [[astrophysics]], accounting for the birth of the [[Solar System]] by interstellar collision. 
He considered [[radiation pressure]] as accounting for [[comet]]s, the [[solar corona]], the [[aurora borealis]], and [[zodiacal light]].

He thought life might have been carried from planet to planet by the transport of [[spore]]s, the theory now known as [[panspermia]].{{sfn|Chisholm|1911}}<ref>Arrhenius, S., ''Worlds in the Making: The Evolution of the Universe''. New York, Harper & Row, 1908,</ref> He thought of the idea of a [[universal language]], proposing a modification of the [[English language]].

He was a board member for the ''Swedish Society for Racial Hygiene'' (founded 1909), which endorsed [[mendelism]] at the time, and contributed to the topic of contraceptives around 1910. However, until 1938 information and sale of contraceptives was prohibited in the Kingdom of Sweden. [[Gordon Stein]] wrote that Svante Arrhenius was an atheist.<ref>{{cite book|title=The encyclopedia of unbelief|volume=1|date=1988|publisher=Prometheus Books|isbn=9780879753078|author=Gordon Stein|page=594|quote=Svante Arrhenius (I859-I927), recipient of the Nobel Prize in chemistry (I903), was a declared atheist and the author of The Evolution of the Worlds and other works on cosmic physics.}}</ref><ref>{{cite web|title=Svante Arrhenius|url=http://www.nndb.com/people/875/000092599/|publisher=Soylent Communications|access-date=11 September 2012|author=NNDB.com}}</ref> In his last years he wrote both textbooks and popular books, trying to emphasize the need for further work on the topics he discussed. In September 1927, he came down with an attack of acute [[intestine|intestinal]] [[catarrh]] and died on 2 October. He was buried in Uppsala.