Abstract:
Background. Elevated concentrations of heavy metals in soil have detrimental consequences on
the environment, which translates into damaging effects on humans.
Objective. An evaluation was carried out to determine the concentrations of seven heavy metals
(As, Cd, Cr, Cu, Hg, Pb, Zn) in soil sediments collected from 12 different stations within the
Benya Lagoon in Komenda Edina Eguafo Abrem Municipality (KEEA) in Ghana.
Methods. The calibration and concentration measurements of the elements were carried out
using a fast sequential hydride generation atomic absorption spectrophotometer.
Results. An assessment according to metal concentration in terms of abundance found that
Pb registered the highest, while a comparison with standard sediment criteria by USEPA and
CBSQG indicated heavy pollution levels of As, Cd, Hg, and Pb. Using Pearson's coefficient
matrix, As-Cd had a correlation of 1.000, while Zn-Pb registered 0.858, indicating the same or
similar source input for each pair. Both the geo-accumulation index (I
eo) and the contamination
factor (CF
gave the extent of contamination in the order Cd > Pb > As > Hg > Cu > Cr > Zn,
while the degree of contamination Cd
at the stations was in the order 1 > 3 > 4 > 5 > 6 > 2 > 7 > 8
> 9 > 10 > 12 > 11, indicating Station 1 as the most polluted. The Hakanson index established the
order of decreasing threat of a potential ecological risk as Cd > Hg > As > Pb > Cu > Cr > Zn.
Discussion. The high sums of the individual potential risks values obtained at the sampling
stations point to a possible detrimental effect on the health of inhabitants that use resources
directly from the lagoon without treatment, and therefore the need for education to curtail
any unanticipated disasters.
Competing Interests. The authors declare no competing financial interests.
