Specific activity levels of radionuclides in spring water, selected plants and soils along Nakivubo channel
Abstract
There is an increase in the number of industries that discharge their effluents into Nakivubo
channel. It is possible that some of the industrial effluents may contain radioactive nuclides since
they are widely used in hospitals, research laboratories, industries and construction for
diagnosing and treating illnesses, sterilizing equipment. All these processes deposit radio-nuclides
into the environment if not well handled contaminating the soil and plants grown on the
soil. This in turn affects people when they ingest these crops leading to cancerous risks. This
study determined the Specific activity levels of the radio-nuclides present in spring water,
selected plants and soils along Nakivubo Channel and its tributaries.
The study was experimentally carried out using a Gamma Ray Spectrometer consisting of a 7.5
em Nai(T1) GDM 20 detector used for analyzing radio-nuclides in the samples for a period of
about 5000s. The spectral peaks of the radio-nuclides present in the samples were noted and their
specific activity calculated.
The radio-nuclides observed in the samples are: Uranium (U-238), Thorium (Th-232) and
Potassium (K-40). The highest specific activity was mainly due to K-40 with a mean value of
201162 ± 448 Bq/kg, followed by Th-232 with a mean activity of 72,7 ± 8,5 Bq/kg and the
lowest was due to U-238 with a mean activity of 34,4 ± 5,9 Bq/kg. This is in agreement with a
study by Anguma ( 1999) in water, fish and water hyacinth in Lake Victoria and Kyoga where K-
40 was more abundant with a mean activity of 610 Bq/kg and the lowest mean activity levels due
to U-232 of 17 Bq/kg.
From the results obtained, the concentrations of the radio-nucleoside identified in the samples were
within the tolerance limits and therefore the people who consumed these food crops are hardly at
a high risk of developing stochastic health effects unless if they are consumed over a lifetime.
However, a study investigating the concentration of radio-nuclides in sugarcane fibre be carried
out. A study to ascertain the annual consumption of the radio-nuclides in foods like yam and
sugarcane, spring water along Nakivubo channel and its tributaries be carried out to identify any
risks if any. A high purity Germanium Spectrometer can be used in this study to improve on the