METHODOLOGY OF RECONSTRUCTION OF INTERNAL DOSES FROM 137Cs AND 134Cs OF RESIDENTS OF RADIOACTIVELY CONTAMINATED...

Area of Science:

• Radiological Sciences
• Environmental Science
• Public Health

Background:

• The Chornobyl (Chernobyl) accident caused widespread radioactive contamination with Cesium-137 (137Cs) and Cesium-134 (134Cs).
• Assessing internal radiation doses is crucial for affected populations, especially where direct measurements are unavailable.

Purpose of the Study:

• To develop and scientifically justify a methodology for calculating internal radiation doses from 137Cs and 134Cs intake.
• To provide a method for dose reconstruction in Ukrainian settlements contaminated by the Chornobyl accident, specifically for residents not monitored by whole-body counters (WBC).

Main Methods:

• Developed a new methodology for reconstructing doses from both surface (1986) and root (1987-2023) contamination of vegetation.
• Utilized theoretical food chain transfer models adjusted with early WBC data for surface contamination.
• Employed an ecological dosimetric model for root intake, calibrated with cow's milk and WBC monitoring data (1987-2013).
• In the absence of WBC data, doses were estimated using regional environmental contamination specifics (soil type, soil and milk contamination levels, milk equivalent).

Main Results:

• A robust methodology for reconstructing internal doses from 137Cs and 134Cs in Chornobyl-affected Ukrainian territories has been established.
• The methodology integrates data from extensive radioecological and dosimetric monitoring conducted post-accident.

Conclusions:

• Annual internal doses for residents without WBC monitoring can be calculated using 137Cs activity in private farm milk.
• Where milk data is absent, a linear regression model linking 137Cs in the body to soil groups is applied.
• Doses calculated via the new methodology show good agreement with those derived from direct WBC measurements.