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Belfast Meeting

Belfast Meeting. UMH Ángel Carbonell Francisco Burló Antonio Signes. Food Safety. SA3. Task “Estimation of daily dietary arsenic intake from water and foods”. Food Safety.

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Belfast Meeting

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  1. Belfast Meeting UMH Ángel Carbonell Francisco Burló Antonio Signes

  2. Food Safety SA3. Task “Estimation of daily dietary arsenic intake from water and foods”.

  3. Food Safety The agreement with RKVM is already signed and RKVM has appointed Ms. Kasturi Mitra, who has submitted her Ph.D. dissertation in March 2005 (Environmental Science). RKVM has already sent rice samples and they have reached Alicante without any problems at the Spanish customs. RKVM is preparing the plot at the site for plant growing using treated water. Besides, samples of crops included in the following table are being collected and air-mail to Spain for analyses.

  4. Food Safety If possible, we will try to get samples from the same items before and after the monsoon to study the effect of this event on As concentration in the crops.

  5. Food Safety Food Habits Survey (Kasturi)  Estimation of As Intake  Evaluation of Risks

  6. Fertilizers SA3. Task “Effect of fertilizers such as phosphates on arsenic mobility in the soil”.

  7. Fertilizers Woolson (1975) concluded that: Low levels of phosphorus added to an arsenic toxic soil will displace arsenic from soil particles to increase the toxicity to plants, but larger applications of phosphorus will compete at the root surface and decrease toxicity. Carbonell-Barrachina et al. (1998) concluded that: Since P can be substituted for As in plant, but is unable to carry out P’s role in energy transfer, the plant reacts as if there is a P deficiency. Thus, as plant As increases, the plant reacts by increasing both P and As uptake.

  8. Fertilizers

  9. Anaerobic Soil Aerobic Soil Highly Moderately Reducing Oxidizing Reducing Reducing C Dioxide ---> Methane Arsenate ---> Arsenite Nitrate ---> Nitrogen Oxygen ---> Water Sulfate ---> Sulfur Mn(IV) ---> Mn(II) Fe(III) ---> Fe(II) 3 2 1 -300 -200 +400 -100 0 +100 +200 +300 Redox Potential (mV) Fertilizers

  10. Air Air Eh-meter Nitrogen Nitrogen Anaerobic System Intermediate Syst. Aerobic System Fertilizers

  11. Fertilizers

  12. Fertilizers

  13. Fertilizers Under oxidizing conditions, As will be eventually co-precipitated and became immobilized by formation of insoluble, hydrated iron oxides. Immobilization will also occur with other high surface-area compounds such as organic matter

  14. Fertilizers Under reducing conditions, sulfides play an important role in retaining As. A high availability of sulfur sources will help to reduce and keep to a minimum As solubility by precipitating arsenic as insoluble sulfides.

  15. Belfast Meeting UMH Ángel Carbonell Francisco Burló Antonio Signes

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