hrvatski

VIŠEGODIŠNJA IZLOŽENOST 226Ra PUTEM PIJENJA VODE

This paper presents a method of calculating the 226Ra effective dose following continuous intake of water. In contrast to other authors who calculated the effective dose based on a single intake of annual amount of water (i.e. 730 L ingested at once) this paper includes continuous intake of 2L of water per day. The method is based on the assessment of cumulated activity including m(t) value which describes the fraction of a unit intake retained in the whole body at time t (in days) after intake. For modelling, simulation, and visualisation of the process depending on time, the Simulink program (from Matlab program package) was used. The created Simulink models offer very simple calculation of cumulated body activity and a consequent effective dose during 20000 days. The dose assessment was performed for the 226Ra specific activity of 5, 50, 1000 and 5000 mBq L-1. Regarding adult organism only, during 20000 days of continuous consumption, 226Ra effective doses rise continuously, reaching from 0.002 mSv (5 mBq) to 2.1 mSv (5000 mBq). However, annual 226Ra effective doses on the 20000th day ranged from 5.23· 10-5 (5 mBq L-1) to 0.05 mSv (5000 mBq L-1) meaning that they are in accordance with WHO's recommendation of 0.1 mSv per year. It can be concluded that 226Ra specific activities above 1000 mBq L-1 consequently could cause effective doses which are below maximally recommended values, but it is still an open question what effect this high 226Ra specific activities could have on child organism.

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nije evidentirano

engleski

LONG-TERM EXPOSURE TO 226Ra IN DRINKING WATER

This paper presents a method of calculating the 226Ra effective dose following continuous intake of water. In contrast to other authors who calculated the effective dose based on a single intake of annual amount of water (i.e. 730 L ingested at once) this paper includes continuous intake of 2L of water per day. The method is based on the assessment of cumulated activity including m(t) value which describes the fraction of a unit intake retained in the whole body at time t (in days) after intake. For modelling, simulation, and visualisation of the process depending on time, the Simulink program (from Matlab program package) was used. The created Simulink models offer very simple calculation of cumulated body activity and a consequent effective dose during 20000 days. The dose assessment was performed for the 226Ra specific activity of 5, 50, 1000 and 5000 mBq L-1. Regarding adult organism only, during 20000 days of continuous consumption, 226Ra effective doses rise continuously, reaching from 0.002 mSv (5 mBq) to 2.1 mSv (5000 mBq). However, annual 226Ra effective doses on the 20000th day ranged from 5.23· 10-5 (5 mBq L-1) to 0.05 mSv (5000 mBq L-1) meaning that they are in accordance with WHO's recommendation of 0.1 mSv per year. It can be concluded that 226Ra specific activities above 1000 mBq L-1 consequently could cause effective doses which are below maximally recommended values, but it is still an open question what effect this high 226Ra specific activities could have on child organism.

N/A

nije evidentirano