Assessment of polycyclic aromatic hydrocarbons in shrimps and crabs and some physicochemical parameters in surface water of New Calabar River

Abstract

This research assessed Polycyclic Aromatic Hydrocarbons in shrimps and crabs, also some physicochemical parameters in surface water. Surface water crab and shrimp samples collected from four (4) different locations (Iwofe waterfront, Mgbuodohia waterfront, Abonnema wharf, and Nembe waterfront) were treated according to laboratory standards and examined for some physicochemical parameters and Polycyclic Aromatic Hydrocarbons (PAHs). The sampling was done between March 2021 to May 2021. The parameters examined include pH, conductivity total suspended solids, total dissolved solids, temperature, oC, Turbidity, salinity, total hardness, Alkalinity, Ammonium, dissolved oxygen, biochemical demand, chemical Oxygen demand, oil and grease sulphate and nitrate, mg/l. It was observed that in all the physicochemical parameters examined, that the which is the dry season march had more prominent values than the wet season may. The polycyclic aromatic hydrocarbons (PAHs) concentration (ppm) examined include the following: Naphthalene, Acenaphthylene, Acenaphthalene, Fluorene, Phenanthrene, Athracene, Fluorantherne, Pyrene, chrysene, Benz (a) anthracene, Benzo(b,k) fluoranthen, Benz(a) pyreneindeno (1,2,3-cd) pyrene, Dibenz (a,h) an thracene, and Benzo (ghi) perylene (ng/g). Analysis in crabs tissue sample: Nembe > Iwofe > Mgbuodohia > Abonnema and crabs exoskeleton sample: Abonnema > Nembe > Iwofe > Mgbuodohia respectively. Results of analysis is shrimps abdomen samples: Mgbuodohia > Nembe > Iwofe > Abonnema while in shrimps head samples: Abonnema > Iwofe > Mgbuodohia > Nembe. The descriptive statistics and one-way Analysis variance (ANOVA) on the variations in physicochemical parameters for the surface water based on locations (Iwofe > Abonnema > Mgbuodohia > Nembe). The difference associated with the site may have originated from the different anthropogenic influences within the sample of rainwater, budging) especially in the case of pH, which has higher values. Analysis of Variance (ANOVA) was used to interpret the results, which showed the significant differences in various locations of the sample. The result of ANOVA revealed, (significant at p> 0.05) that, there is no significant difference in the mean levels of physicochemical parameters and polycyclic aromatic hydrocarbons (PAHs) between the two shellfish (shrimps and crabs) species. The result obtained was within the permissible limit(s) or standard set by WHO, USEPA, and NAFDAC. It is therefore recommended for State Government to constantly monitor the water bodies of the New Calabar River, Nigeria.