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Iodouracil as a personal dosimeter for solar UVB
1Department of Environmental Health, University of Alabama at Birmingham 35294, USA.
Photochemistry and Photobiology
|September 2, 1998
Summary
A novel UVB dosimeter uses iodouracil and potassium iodide (KI) to detect ultraviolet B (UVB) radiation. The intensity of the blue starch-iodine complex formed is proportional to UVB exposure, enabling personal monitoring.
Area of Science:
- Photochemistry
- Analytical Chemistry
- Environmental Science
Background:
- Ultraviolet B (UVB) radiation poses health risks and requires accurate monitoring.
- Existing UVB monitoring methods can be complex or lack personal applicability.
Purpose of the Study:
- To develop a simple, cost-effective method for quantifying UVB exposure.
- To assess the feasibility of a personal UVB dosimeter based on a chemical reaction.
Main Methods:
- A solution of iodouracil and potassium iodide (KI) in borate buffer was exposed to UVB from a sunlamp or solar irradiation.
- The formation of triiodide was detected by the blue starch-iodine complex, with intensity measured spectrophotometrically or densitometrically.
- UVB selectivity was confirmed using a UVB cutoff filter.
Main Results:
- The intensity of the blue starch-iodine complex showed a direct correlation with UVB exposure.
- The system demonstrated selectivity for UVB radiation, with significant yield reduction when filtered.
- A consistent quantum yield of approximately 1% was calculated for the reaction.
Conclusions:
- The iodouracil-KI system effectively quantifies UVB exposure.
- This system is suitable for development into a personal dosimeter for monitoring solar UVB.
- Quantitative or visual estimation of UVB exposure is possible with this method.