01-05 December 2025
INCOIS, Hyderabad, India.
| Abstract Submission No. | ABS-01-0150 |
| Title of Abstract | Spatial and Temporal Distribution of Polycyclic Aromatic Hydrocarbons (PAHs) in major creeks along the Kenyan coast |
| Authors | Maurine Kerubo Arori*, Marie-Alexandrine Sicre, Vincent Klein, Agnes Muthumbi, Jacqueline Uku |
| Organisation | Department of Biology, University of Nairobi, P.O. Box 30197-0010 |
| Address | 3 Rue Michel-ange Paris, Paris, France Pincode: 75016 E-mail: marie-alexandrine.sicre@locean.ipsl.fr |
| Country | France |
| Presentation | Oral |
| Abstract | Polycyclic Aromatic Hydrocarbons (PAHs) were analyzed in surface and core sediments from three major creeks along the Kenyan coast: Mwache, Tudor and Mida. The total concentration of the 16 priority PAHs in surface sediments ranged from 7.19 to 100.28 ng g⁻¹. Alkylated PAHs, primarily methyl-phenanthrene, were also found in Mwache Creek varying from 1.06 to 5.56 ng g⁻¹. Highest PAH levels were found in Mwache and Tudor peri-urban creeks, subject to high population density and anthropogenic activities, while the lowest levels in Mida creek reflect its status as a marine protected area and the slow pace urbanization in the region. 210Pb dating indicate that sediment cores provide a PAHs deposition history since the early 1900s at Mida and Mwache creeks but only from the 1980s for Tudor creek. Downcore total PAH concentrations ranged from 6.5 to 43.1 ng g⁻¹ in Mwache, 5.2 to 23.7 ng g⁻¹ in Tudor and from 1.5 to 10.0 ng g⁻¹ in Mida. The top core PAH values are consistent with mean PAH surface sediment concentrations at each site. Downcore profiles all show increased PAH accumulation in the recent decades with highest values in Mwache and Tudor Creeks. Positive Matrix Factorization (PMF) was used for PAH source apportionment. For surface sediments, gasoline engine emissions (33.86%) and biomass burning (33.11%) were major sources followed by diesel engine emission (16.71%) and petroleum products (16.24%). PMF applied to downcore PAH profiles at each site identify different local sources. In Mwache, petroleum PAHs, attributable to harbor activities, accounted for almost half of the variance (47%). In Tudor, gasoline engine emissions (31%) and oil (27%) prevailed, while at Mida, biomass burning (29%), diesel engine (27%) and gasoline engine (25%) emissions contributed at almost equal levels. In conclusion, this baseline study provides useful information of trends in urbanization and coastal ecosystems exposure for coastal water quality monitoring and mitigation strategies adapted to each site to beat coastal pollution. |
| Are you part of IIOE-2 endorsed project | yes |
| Endorsed Project Number | IIOE2-EP55 |
| Keywords | PAHs, contamination, coastal waters, Kenya sediments |
| For Awards | yes |
| Date Of Birth | 22-07-1960 |
| ECSN Registration Number | IIOE2-ECSN-0127 |