S. ZARMAI ET AL.
742
agent in pharmaceuticals, fossil fuel combustion and light-
sensitive photoconductor layer in photocopiers [4]. Con-
sequently, as we consumed a varied diet obtained from
many geographical locations, it is not likely that sele-
nium deficiency in the soil in a few areas will cause sele-
nium deficient in Central Nigerians’ diet. Individual in-
takes will differ about the determined mean, depending
on the amount of protein in the diet and in particular on
the amount of selenium rich foods which are consumed
[15].
There have been many documented maximum intakes
of selenium. The National Academy of Science [11] re-
ported 450 μgSe/day while selenium intake of 400 μgSe/
day has been recommended by WHO [12]. According to
Food Standard Australia New Zealand (FSANZ) [16]
quoted Australian RDI to be 85 μgSe/day and Nordic
project [17] considered an intake of 280 - 350 μgSe/day.
Comparison of our analytical results with the litera-
tures, it was observed that good food sources of selenium
were sweet potato and yellow yam. Yam and cassava
contained some significant content of selenium and it is
unlikely that selenium deficiency occurs in Central Nige-
ria. The values obtained were far below those intakes
referred to as the unsafe dose.
4. Conclusion
Analysis performed by using HG-AAS technique for Se
content indicated that few samples contained below the
detection limit while most samples contained relatively
large content of the element. The different levels of Se in
these roots and tubers investigated could be due to spe-
cies or variety differences, total Se concentration in the
soil where they were grown, bioavailability of Se in the
soil, and local anthropogenic activities; this requires fur-
ther investigation to be more conclusive. However, since
the mean selenium content in the four roots and tuber
staples revealed that sweet potato contained the highest
Se, followed by yellow yam, then yam and cassava the
least, and considering the importance of Se nutrition to
the health conditions of certain populations, it is recom-
mended that sweet potato should be made to be a more
popular staple rather than cassava, which is now the most
popular one.
5. Acknowledgements
The authors are highly grateful to the immediate family
members for their support and encouragement. Our ap-
preciations also go to the members of staff Fugro Nig.
Ltd. Port-Harcourt for given us opportunity to use their
laboratory for this research work. We are also grateful to
the anonymous reviewers for their suggestions which
brought our report to this level.
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