Blood Retention Pattern of Polycyclic Aromatic Hydrocarbons in Guinea-Pigs Treated with Crude Oil

Exposures to crude oil are common among oil workers and rural populace and contribute a global health burden. The aim of this study is to investigate the blood retention patterns of polycyclic aromatic hydrocarbons (PAHs) in guinea pigs treated with bonny light crude oil (BLCO). The objective of the study was to find out if there is a peculiar pattern of retention of PAH after exposure to crude oil. Fifteen adult male guinea pigs were used for the research and separated into five groups of three animals. All animals were fed with freshly cut elephant grass daily ad libitum. Group 1 served as the control (untreated) group. Group 2-6 were treated liberally with crude oil by skin application (dorsal side of ear) once. The sacrifices were done at 1, 2, 3 and 4 hours interval. Blood samples were collected and extracted with dichloromethane (DCM) and concentrated before GC-MS analysis. The chromatogram shows 14 PAHs absorbed and retained in the blood after 1hr exposure.4 out of the 14 absorbed PAHs were still retained in the blood up to 2hrs after skin exposure. The chromatogram for 3 & 4 hrs show no retained PAHs but contained peaks which might be indicative of other PAHs. The results obtained from this study reveal that PAHs have a clearance time of approximately less than 4hrs in the blood and that its metabolites may cause carcinogenesis if it forms conjugate with DNA at site critical for cell growth.