Can anyone suggest me a simple and efficient and detailed method for iodine determination in soils, plants, and waters?

i no longer am associated with HCTM, Kaithal since last May. I can be contacted as a Free lance technology consultant/advisor at <nnath32@ymail.com>. My association with Kurukshetra University's Physics department started as professor from 1970 and lasted till 1995. My patents filed have provided me some capability to help others in some technological areas that border with physical sciences and instrumentation, as we did substantial development studies along with research during the long period at Kurukshetra University

Association of Official Agricultural Chemists (A.O.A.C.) publication is the standard referenc text available for analytical techniques available for elemental analysis of various organic and inorganic materials of which iodine is one. Please refer the same for details.

There are International standards available from NIST, USA called Standard Reference Materials and these can be used to calibrate and standardize any procedure used for quantitative estimation.
Narendra Nath

Iodine concentration in plants was measured using the U.S.
Environmental Protection Agency method 3052 [nitric acid (HNO3)–hydrogen peroxide (H2O2), microwave digestion] and an inductively coupled plasma mass spectrometry
(ICP-MS) analysis procedure.
The closed digestion was performed by placing the sample in a polytetrafluoroethylene
(PTFE) vial (or bomb). After adding the digestion reagents (10 mL HNO3 65% and 2 mL
H2O2 30%), the bomb was hermetically sealed and placed in a microwave oven for irradiation. The determination of iodine by ICP-MS was performed by using isotope dilutions.

and iodine concentrations in the samples were determined by means of a calibration
curve obtained with the method of standard additions (Larsen and Ludwigsen 1997).
To assess the iodine accumulation efficiency (AE) of the two plant organs analyzed,
their agronomic efficiency of accumulation was calculated using the following simple
equation:
AE =
total amount(µg) of iodine in tomato fruits or potato tubers harvested
total amount(µg) of iodine applied
× 100

Thank you all for you encouraging coments and advices. I shall look into all but it also depends upon the availabilty of required equipments. Yours suggestions are quite helpful and hope to resolve my queries.

There is a cheaper way to implement EDXRF technique if one needs to determine single element at a time. One uses balance filters that cut out flourescent X-rays generated by elements on either side of say Iodine and then detect uniquely the iodine content - using an ordinary NaI (Tl) detector, instead of Si detectors that require cryogenics and costly electronic measurement equipment. This modifies the comments made earlier.
Narendra Nath

AUTOMATED PLANT AND SOIL ANALYSIS

APPLICATIONS OF SEGMENTED-FLOW ANALYZERS FOR PLANT AND SOIL ANALYSIS
SFA methods for Plant and Soil Samples
 Aluminium
 Ammonia
 Amino (dissolved organic)
 Carbon total
 Phosphate
 Phosphorus, total
 Potassium
 Soluble In laboratories around the world the SEAL AutoAnalyzer 3, the pioneer of automated analysis, delivers fast, more accurate, routine analysis of soil and plant samples for nutrients and minerals. Results are calculated and printed automatically at 40 - 90 samples per hour, thus improving productivity and cost-effectiveness. The Seal QuAAtro provides high speed analysis to the largest laboratories.
SAMPLE PREPARATION
Soil
Samples are normally dried, screened to remove stones and ground before extraction. Many extraction procedures have been developed to provide an estimate of the soil's supply of nutrients available to crops. Some of the most common are dilute acid, calcium chloride, bicarbonate, ammonium acetate and electro-ultrafiltration . Calibration standards are prepared in the sample extraction solution to ensure accurate results. Methods are available for all common sample preparation procedures. The automated soil methods can easily be adapted for plant and fertilizer analysis.
Ashing
Applications: P, Ca, Mg, Mn, K, Na, Al, B, Cu, Zn, Fe, I.
Samples are dried, normally at 105 °C, ground, and a representative sample, typically around 1g, is ashed at 500 - 550 °C. The cooled residue is dissolved in dilute acid and diluted to volume. Alkaline ashing is used prior to iodine determination to prevent loss of I2.
Acid Digestion
Applications: N, P, Ca, S.
Kjeldahl digestion is required for total N: P and Ca can be determined from the same digestate. Sulphur requires digestion with HNO3, HCl and/or HClO4, or dry ashing with Mg(NO3)2. Methods are available for all common sample preparation procedures; several are AOAC approved.
Soil and Plant Specific Multitest Methods
Specially developed for Plant and Soil analysis, these Seal Analytical multitest methods enable you to measure several different parameters with one analytical cartridge or manifold. When changing from one test to another only the reagents and the colorimeter filter need to be changed.

Use When Some Tests are Required Occasionally
Multitest methods are ideal for laboratories with small to medium workloads, or where some tests are required only occasionally, as there is no need to invest in a separate manifold for each chemistry.

Please, try this: http://www.tandfonline.com/doi/abs/10.1080/00103629609369591. I think You will find something about iodine on soil and plant.

Polarographic Determination of Iodine in Water, Soil, and Plant Material
P Godfrey, H Parker, F Quackenbush
Anal. Chem., 1951, 23 (12), pp 1850–1853

Very good question. please can visit National Research centre

I am dealing with remote sensing applications in agriculture and environment. I have not a direct expertise to give you an advice. I would suggest you to make a query in Google Scholar (Academic).

The technique mentioned will also quantify the trace and constituent elements present in soil samples--a complete analysis is possible but not the nature of compound formed for which one may resort to Mass Spectroscopic analysis.

There is a non-destructive technique called Energy-dispersive X-ray Fluorescence Analysis. It can not ony determine Iodine content but other elements too from Carbon to Uranium down to ppm sensitivity.
Narendra Nath <nnath32@ymail.com>

How about using autotitrator attached with iodine probe? This one always uses for measing iodine in biodiesel oil. I think it should be used for yours.

The main method is extrating by TMH and analysing samples on ion exchange chromatography (Dionex). Few analysts tried with ICP method. But rare to see good results. How about any colorimetric method?