Arsenic in Ironite fertilizer: The absorption by hamsters and the chemical form

Abstract

We determined the gastrointestinal absorption of the arsenic in Ironite, a readily available fertilizer, for male hamsters (Golden Syrian), considered to be an excellent model for how the human processes inorganic arsenic. Urine and feces were collected after administering an aqueous suspension of Ironite by stomach tube. In addition, we studied the forms and oxidation states of arsenic in Ironite by synchrotron spectroscopic techniques. The absorption of the arsenic in Ironite (1-0-0) was 21.2% and the absorption relative to sodium arsenite was 31.0%. Our results using XANES spectra determinations indicate that Ironite contains scorodite (AsV) as well as previously reported arsenopyrite (As(−1)). Since the 1-0-0 Ironite is readily available for purchase, its risk assessment for children by professionals is recommended. This is especially important because it is used to fertilize large areas of grass in playgrounds and parks where children play. The absorption of the arsenic in it, the hand to mouth activity of children, and the potential of ground water contamination makes the use of 1-0-0 Ironite as a fertilizer a potential environmental hazard.

Keywords:

• arsenic
• fertilizer
• arsenic absorption
• Ironite
• children
• risk assessment

Acknowledgments

Supported in part by Superfund Basic Research Program NIEHS (Grant No. ES-04940), Southwest Environmental Health Sciences Center (Grant No. P30-ES-06695) from the NIEHS, Wallace Research Foundation and an NSERC Strategic Projects (Grant No. STPGP235041-00) at RMC (ESG). PNC-CAT is supported by the U.S. DOE, Basic Energy Sciences (Contract No. DE-FG03-97ER45628), the University of Washington, an NSERC major facilities access grant (Simon Fraser University) and the Advanced Photon Source, supported by the U.S. DOE, Office of Science, Office of Basic Energy Sciences (Contract No. W-31-109-Eng-38). We thank Dr. Robert Gordon, beamline scientist, and Elizabeth Duncan (University of Aberdeen) for their assistance with the synchrotron work.