Qualifying%20Exam

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Qualifying Exam
Midterm evaluation (Part A), Department of
Geoscience
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Project

• Geocenter project, financed by GEUS and AU (2011-
  2014)
• Project title Iodine in the hydrological cycle
  in Denmark implications for human health
• Objective to combine both the medical and the
  geochemical aspect by studying the variations in
  iodine bioavailability in groundwater and to
  evaluate the human health effects.
• Søren Munch Kristiansen
• Birgitte Hansen
• Kim Esbensen
• Vibeke Ernstsen
• Brian Sørensen

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Presentation outline

• PhD objective and structure
• Background information
• Summary of potential research topics
• 1st part of the PhD Multivariate analysis of
  historical groundwater data
• 2nd part Four case studies
• 3rd part National study
• Future plans

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PhD objective and structure

• To investigate the spatial variation of iodine
  concentrations and speciation in the Danish
  ground- and drinking water.
• To elucidate the sources and processes
  influencing this variability by focusing on the
  geological and geochemical causes
• Geoavailability, bioaccessibility and
  bioavailability of I and the human health effects.

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groundwater formation and Danish geology
sources Viden om grundvand and Den Store Danske
open encyclopedia
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From groundwater to Tap water
Type of organisation ww with reported abstractions ww with reported abstractions Reported abstraction volumes mio m3 / year Reported abstraction volumes mio m3 / year
Type of organisation 2010 2011 for 2010 for 2011
Small (3-9 households) 249 271 0.842 0.954
Public 337 326 216.707 208.125
Private 2246 2120 179.464 170.616
Water supply 2 1 0.875 0.852
Sum 2834 2718 397.888 380.547
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Iodine cycle
No data
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Iodine essential trace element
regulates the metabolic processes in cells plays
role in the early development of most organs
group RNI ug/day (WHO) UL ug/day (European commision) UL ug/day (IOM, US)
0-5yeras 90 200-250 200-300
6-12years 120 250-450 300
12-17 years 150 450-500 300-900
adults 150 600 (500) 1100
pregnant 200 600 1100
Expert committee on Human Nutrition, France
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Iodine Deficiency
Median UI ug/l associated risk
Severe ID lt20 cretinism, goitre, hypothyroidism, etc.
Moderate ID 20 - 49 low IQ, goitre, hypothyroidism, hyperthyroidism
Mild ID 50 - 99 goitre, hyperthyroidism
Optimal ID 100 - 199 -
More than Adequate (Excessive) 200 299 (gt300) hypothyroidism, early Graves disease (?), (goitre)
source Laurberg at al. 2010
Source WHO 2007

• mild ID Denmark (10 other European countries)
• subnational surveys Denmark ( 13 other
  European countries)

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Short historical overview
Denmark must be regarded as area with marginal
iodine deficiency, and in the elderly population,
especially among women, goitre is present with
high frequency (Rasmussen et al. 1996)
decision
voluntary fortification
DanThyr

• cohort studies
• register of new cases of hyper- and
  hypothyroidism
• national register for surgical, medical, and
  radioiodine treatment

mandatory
Pedersen et al. 1997
cover the main difference in levels of iodine
intake in Denmark caused by different levels of
iodine in groundwater...
(Laurberg et al. 2006)
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Dietary iodine
geographical temporal (?) variation
data A.N. Pedersen at al. 2010 -gt dietary habits
in Denmark (n4431)
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Urinary Iodine excretion studies, Denmark
Samples 24-hour or spot units!

• One national study Munkner 1969
• 17-20 years old male gymnasium students,
• mediane 64 ug/24-hours
• Recent studies are evaluating the effect of the
  fortification program (DanThyr)

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Iodine Bioavailability
Bioavailable iodine is that which is absorbed
from the food and utilized to produce thyroid
hormones. Hurrell, 1997

• Controlling factors
• Iodine intake
• Nutrient interactions
• Goitrogens

dietary intake inorganic org. iodine
synthesis of thyroid hormones
transport of iodide, bound to plasma proteins
conversion to iodide
The ideal method to measure iodine
bioavailability in man would be to use
radioiodine and to quantify urinary and faecal
excretion as well as thyroid uptake. Hurrell
1997
urinary iodide excretion
faecal excretion endogenous org. iodine
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Goitrogens and other factors
Goitre endemias from naturally occurring
goitrogens in food
smoking malnutrition other deficiencies
Humic substances
data Gaitan, 1990
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Summary of potential research topics

• Spatial variability of I concentration and
  speciation from drinking water and groundwater
• Temporal variation of I concentration and
  speciation from drinking water combined with the
  variation in milk
• Bioavailability of I and I species
• Combined effect of I and other chemical elements
  from the drinking water on the human health (e.g.
  water hardness, Li, Fe, Se, etc.)
• Recognising population groups with potential
  insufficient intake based on the variability of I
  concentration and speciation in water
• Correlation between I intake from water and
  registered cases of IDD on municipality scale for
  whole Denmark

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1st part Multivariate analysis of historical
groundwater data

• Objectives
• To identify the factors (both I sources and key
  processes) governing I content in Danish
  groundwater
• To find out in what way the I content is
  influenced by these factors

• Methods and materials
• Data from Jupiter The Danish public nationwide
  geological and hydrological database
• Multivariate data analysis PCA PLS-R
• Traditional geochemical tools redox type
  saturation indexes Na/Cl ratio and Cl/Br ratio

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1st part
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(No Transcript)
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1st part Outcome

• Data quality !
• Interpreting the positive correlation of
• I to Ba, HCO3-, Br, Na and partially Fe, and the
  negative correlation of I to distance to the
  coast line, major faults, and pH
• Specifying one dominating source of I is not
  consistent with the general complexity revealed
  by the MVDA
• Studying the I variation on a smaller scale would
  most probably give better results

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2nd part 4 Case studies, Sampling sites

• Skagen 4 wells
• Oust Mølle 4 wells
• Bunkedal 3 wells
• Østrup Skov 3 wells
• Vilstrup 4 wells
• Ishøj 4 wells two depths at 1 well
• Stevns 1well (3 depths)

• Lab measurements I, IO3, TI, DOC, TIC, TN,
  NO3, NH4, Alkalinity, Cl, PO4, SO4, Br, F, Ca,
  Mg, K, Na, Fe, Mn
• Field measurements pH, O2, t, conductivity,
  redox

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2nd part Objective

• To compare and explain the I concentration and
  speciation in the groundwater and its spatial
  variation on different scales, between the wells
  
• at one waterwork
• from different waterworks in one area (Randers)
• from different areas (Skagen vs. Randers).
• To compare and explain the differences/similaritie
  s between I concentration and speciation in raw
  groundwater and drinking water (for both Skagen
  and Randers)
• To elucidate the I sources and the governing
  processes by using hydrogeochemical tools (and
  MVDA).
• Two hypotheses about the I origin are going to be
  tested
• seawater intrusion at the aquifer (Ishøj)
• upward transport (advection) of old saline water
  (Stevns)

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2nd part Sampling
type of well
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2nd part
Pure drinking water sampling
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3rd part National Sampling Campaign Objective

• overview on I speciation in Danish drinking water
  for first time
• concluding on the spatial variation of I and
  confirm/oppose previous findings, questioned
  because of the sampling campaigns design
• optimizing the estimation of the dietary I intake
  from water (higher resolution)
• evaluate the correlation with other chemical
  elements
• distinguishing between types of water or regions
  where it is present and to assess the relevance
  for I deficiency
• correlation with epidemiological data for chosen
  I related diseases on a municipality level

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3rd part

• Selection criteria
• The largest waterwork in each municipality
• The largest waterwork for each cell
• Checking and substituting of some of the chosen
  waterworks for bigger ones

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Plans for the future

• PHD thesis consisting of at least 3 publications
• High-Iodine Danish Groundwaters a Multivariate
  Data Analytical Survey
• Sources and Speciation of Iodine Four Danish
  Case Studies
• Speciation of Iodine in Danish Drinking Water
  a Nation-wide Assessment
• Estimation of Dietary I Intake from Water and
  Assessment of the ID Risk on Municipality Level
  (tentative).
• Other ?