THE OCCURRENCE OF ARSENIC IN SOILS 



J. E. GREAVES 



(Utah Experiment Station, Logan) 



Introduction. KunkeP showed the presence of arsenic in many 

 rocks and waters, while Czapek^ states that traces are nearly always 

 present in soils. Herzfeld and Lange^ found arsenic in certain 

 German raw sugars, and traced it to the lime which had been used 

 in the manufacture of the sugar. Headden^ found some virgin 

 prairie soils relatively rieh in arsenic, an Observation in accord with 

 my own experience. I have found arsenic to the extent of 4 parts 

 per million in virgin soil ; and, as in the cases ref erred to by Headden, 

 it did not result from smelter fumes or any such source, but was 

 derived from the decay of native rocks. On the other band, 

 Headden found arsenic in some cultivated orchard soils to the 

 extent of 138 parts per million. He claims that in many places 

 arsenic is accumulating in sufficient quantities to become injurious 

 to Vegetation. Francois,*^ however, considers there is little danger 

 of the earth becoming unfit for Vegetation from the proper use of 

 insecticides. Grunner,^ who found arsenic to the extent of from 

 0.026 per cent. to 1.426 per cent. in the Reichenstein soil, is not so 

 optimistic. It appears, however, that it is not so much the total 

 quantity of arsenic present as the form in which the arsenic occurs, 

 that determines toxicity. Little work has been done on this phase 

 of the question. I have therefore determined the quantity of arsenic, 

 both total and water-soluble, in many of the orchard soils of West- 

 ern America, and it is the purpose of this paper to consider briefly 

 a few of these results. 



Experiments. The water-soluble arsenic was determined by 



1 Kunkel: Zeitschr. f. physiol. Chem., 1905, xHv, p. 511. 



2 Czapek : Biochemie der Pflanzen, 1905, ii, p. 862. 



3 Herzfeld and Lange: Chem. Abs., 1911, v, p. 2342. 

 * Headden : Proc. Col. Sei. Soc, 1910, ix, p. 345. 



^ Francois : Rev. de chim. ind., 1912, xxiii, p. 124. 

 ^ Grunner: Landw. Jahrb., 1910, xl, p. 517. 



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