Abstract: The Okpare River, a tributary of the Niger Delta, plays a crucial role in sustaining numerous communities in the Olomu kingdom, Delta state, Nigeria. Unfortunately, the river has been significantly affected by oil spills resulting from illegal bunkering activities in the Okpare community. Given that crude oil is a source of polycyclic aromatic hydrocarbons (PAHs), understanding their source, distribution and ecological risk is imperative for developing effective mitigation strategies and safeguarding the ecosystem health. This study utilized the risk quotient method and diagnostic ratio to determine the ecological risk and the sources of the 16 priority PAHs listed by USEPA in the surface water of Okpare River. Samples were collected for 12 months, encompassing both wet (May 2022 to October 2022) and dry seasons (November 2022 to April 2023). A total of eighty-four Samples were obtained from seven sampling stations positioned 100 meters apart along the Okpare river. All samples were collected and analyzed adhering to the standard methods and procedures. Among the 16 priority PAHs determined Benzo(b)fluoranthene concentrations with average values of 46.50 ng/L and 13.17 ng/L had the highest concentration in the wet season while dibenz (a, h) anthracene levels with average values of 24.00 ng/L and 53.00 ng/L was higher in the dry season. The distribution of PAHs in the Okpare River in the wet season was in the order 5 rings > 6 rings > 4 rings > 3 rings > 2 rings; the order of magnitude in the dry season was 6 rings > 5 rings > 4 rings > 3 rings > 2 rings. BaA, BbF, BkF, BaP, InP, DBA, and B(ghi)p posed a high ecological risk in the wet season, while BbF, DBA, and B(ghi)p demonstrated high ecological risk during the dry season. The source of PAH in this study may be due to pyrogenic and petrogenic sources. Effective mitigation strategies should target these pollution sources, underscoring the importance of adopting sustainable practices to preserve the ecological balance of the Okpare River and enhance the well-being of adjacent communities.
Keywords: Ecological Risk, Petrogenic, Pollutant, Okpare, Risk Quotient, Season.
Title: The Distribution and Ecological Risk Assessment of Polyaromatic Hydrocarbons in the Surface Water of Okpare River, Olomu, Delta State, Nigeria
Author: Lily Chovwe Diejomaoh, Duke Okoro
International Journal of Recent Research in Physics and Chemical Sciences (IJRRPCS)
ISSN 2350-1030
Vol. 11, Issue 1, April 2024- September 2024
Page No: 1-9
Paper Publications
Website: www.paperpublications.org
Published Date: 22-April-2024
