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Copyright (c) 2023 Denitza D. Voutchkova
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Abstract
Iodine is an essential element for human health, and both high and low iodine intake could have negative health outcomes. The spatial variation of iodine in Danish groundwater has been studied before, but to the author’s knowledge, this is the first time that the temporal variation is characterised. Nationwide data from the Danish groundwater monitoring programme (GRUMO) were analysed between 2011 and 2021, including 2924 samples from 1242 well screens at 893 wells. The sampling frequency varied and so the robust coefficient of variation (rCV) was calculated for 930 (75%) of well screens, and time-series analysis was performed for 23 (2%). Key findings are (1) iodine in Danish groundwater varies over time (0–124%, median = 10%), (2) in one quarter of the well screens rCV exceeds 20% and (3) this variation cannot be attributed solely to analytical uncertainty at 14% of the well screens. The impact of temporal variation of iodine in Danish drinking water of groundwater origin should be evaluated in future exposure or epidemiological studies with respect to the study goal, location and time period. Since the temporal variation could not be quantified over the entire concentration range, monitoring of iodine in Danish groundwater should continue.
How to Cite
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Copyright (c) 2023 Denitza D. Voutchkova
This work is licensed under a Creative Commons Attribution 4.0 International License.
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An annual collection of articles submitted to GEUS Bulletin and published throughout 2023. Published online only. This issue is open until the end of 2023.
Cover photo: satellite image is from the European Space Agency’s Copernicus Sentinel data 2023, as featured in Karlsson et al. 2023: A data set of monthly [...]
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