The start of my PhD research into iodine Olivier Humphrey

Hi, my name is Olivier and I have just started my PhD within the Centre for Environmental Geochemistry (University of Nottingham and the BGS). My research revolves around iodine geodynamics and plant uptake. This is an important and worthwhile research project because iodine deficiency affects around 2 billion people worldwide. Iodine deficiency diseases (IDD) have a range of effects including goitre, growth impairment and mental retardation. My work will help to inform practical strategies to tackle iodine deficiency, such as correct land management and biofortification of iodine into crops. Parent material contributes very little to iodine concentrations is soils. Soil-iodine is predominately derived from volatilized methylated forms in seawater, which enter the soil-plant system via rainfall and dry deposition. Whilst coastal-proximity is an important factor in iodine concentrations, many other soil characteristics contribute to its mobility and availability once deposited in soils.

The main aims of my PhD research are to: develop methods for identifying organically-bound species in soil solution, investigate whether plant uptake is active or passive and to improve the model assessing the dynamic relationship of iodine in soils.

So far…I am becoming familiar with relevant literature and developing laboratory skills that will be required throughout the course of my PhD. I have been conducting microwave TMAH iodine extractions on vegetation samples collected from Tanzania and plan to measure total iodine concentrations in these samples using ICP-MS.

In order to accomplish the aims of this research project, a comprehensive array of laboratory experiments are required: pot trials, using a wide range of English soils, will be spiked with iodide and iodate in a variety of inputs methods, including (i) progressive addition in irrigation and (ii) initial addition. Grass will also be grown and I-129 isotopic labelling techniques used to distinguish the dynamics processes controlling iodine mobility and plant uptake.

The results of these experiments will ultimately lead to a better understanding of iodine geodynamics and will be used to develop a variety of practices to help improve iodine concentrations in food therefore reducing the number of people suffering from IDD.

More blogs when I get some data!

PhD is supervised by Dr Scott Young, Dr Liz Bailey and Professor Neil Crout (University of Nottingham) and Dr Michael Watts and Dr Louise Ander (BGS)