TITLE:
Assessment of Heavy Metals Pollution in Sediments from Ologe Lagoon, Agbara, Lagos, Nigeria
AUTHORS:
Moyosoluwa Odunayo Adeyemi, Johnson Adedeji Olusola, Oghenemaro Akpobasah, Nathan Eyituoyo Adidi, Rafiu Olaniyi Dada Shelle
KEYWORDS:
Heavy Metals, Wet Environments, Geo-Accumulation Index, Ologe Lagoon
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.7 No.7,
July
24,
2019
ABSTRACT: This
study was carried out to assess the level of heavy metals pollution in Ologe Lagoon, Agbara, Lagos,
Nigeria. The Lagoon receives effluents from industries in the Agbara Industrial
Estate. Cored Soft sediments were retrieved from six random sampling points within the Lagoon and labeled (S1, S2, S3,
S4, S5 and S6). Subsamples of the sediments were prepared and analyzed for
heavy metal concentration. The result from the heavy metal analysis of the
sediments shows that average concentration of Mn, Zn, Cr, Ni, Cr, Ni, Co, Cu
and Pb in the samples was 278.1 ppm, 21.7 ppm, 14.2 ppm, 6.6 ppm, 6.4
ppm, 6.4 ppm and 4.4 ppm, respectively. The correlation between the heavy
metals varies from 0.71 to 0.98 shows that they have a strongly positive degree
of association which suggests that they are from the same source. The
geo-accumulation values for Cu in all stations ranged between (1 - 2.8 ppm) and it can be deduced that the sediments are moderately to strongly
polluted. Pb varies between 1 and 2.1 suggesting that the sediments are
moderately polluted. Zn exhibits strong pollution levels with a range from 2.5
and 3.5 ppm. Co is moderately polluted with 1.5 - 2.4 while Mn shows the
highest level of pollution in all stations with Igeo values ranging
between 4.1 and 5.8. This study showed that the Lagoon accumulates heavy metals
as a result of anthropogenic activities evident in the dumping of municipal, sewage, industrial waste in the
environment and domestic activities such
as auto mobile transportation and mechanic repair workshop. Based on sediment
quality guidelines, the Ologe Lagoon level of pollution ranged from Cu > Pb > Zn > Ni > Co > Mn > Cr > Al with Mn having the highest level of
pollution.