In vivo Efficacy of Ferrihydrite as an Enterosorbent for Arsenic: Short-Term Evaluation in Rodents Academic Article uri icon

abstract

  • The use of dietary adsorbents to reduce arsenic (As) exposure is innovative. Ferrihydrite successfully sorbs arsenite and asenate over a wide range of pH conditions and the As-ferrihydrite complexes are stable in gastrointestinal (GIT) models. Our objectives were to (1) compare structural characteristics (using x-ray diffraction and Fourier-transform infrared [FTIR] spectroscopy) and As binding affinities of industrially produced ferrihydrite (IDF) and lab-synthesized ferrihydrite and (2) evaluate the efficacy of the material displaying the best sorption capability as an As enterosorbent in a short-term mammalian model. Lab-synthesized ferrihydrite displayed superior binding affinity for both arsenate and arsenite in vitro, which led to its use in the in vivo portion of the study. Young Sprague-Dawley male rats were fed either a control diet or a 0.5% w/w ferrihydrite feed. After 1 wk of acclimation, rats were given 0.5 ml of 500 mg/L arsenate or arsenite via gavage with or without ferrihydrite. Rats were then transferred to metabolism cages, and urine collected after 24 and 48 h was analyzed for total As. Rats were evaluated daily for signs of morbidity and mortality for up to 1 wk. Ferrihydrite reduced mean urinary As levels by 74.9% and 43.6% after 24 h and 49.1% and 39.5% after 48 h for arsenite- and arsenate-treated groups, respectively. Importantly, treatment groups receiving ferrihydrite displayed no signs of As-related toxicity. All As reductions were statistically significant except for arsenate treatments at 24 h. Data suggest that, as an enterosorbent, ferrihydrite reduces bioavailability after As exposures.

altmetric score

  • 0.5

author list (cited authors)

  • Taylor, J. F., Robinson, A., Mitchell, N. J., Marroquin-Cardona, A., Johnson, N., Elmore, S. E., Romoser, A. A., & Phillips, T. D.

citation count

  • 1

publication date

  • February 2013