POLYCYCLIC AROMATIC HYDROCARBONS, LEAD AND CADMIUM CONTENTS OF CRUDE OIL CONTAMINATED WATER SAMPLES FROM WARRI, DELTA STATE
ABSTRACT
Polycyclic aromatic hydrocarbons (PAHS) are group of organic compounds, consisting of two or more fused aromatic rings. The main purpose of this research is to determine the PAHS lead and cadmium contents of crude oil contaminated water samples from Warri, Delta state using Quality Analzer and Quality control method. Significantly high concentration of PAHS was found in water samples of Warri, Delta. PAHS concentrations detected in this study is higher. The PAHS patterns in water suggest the dominance of high molecular weight compound. They occurrence of PAHS in the marine environment has attracted the attention of the scientific community as these compounds are frequently detected in seawater at increasing levels and can have adverse effects on marine organisms and humans.
CHAPTER ONE
- INTRODUCTION
Polycyclic aromatic hydrocarbons (PAHS) are group of organic compounds consisting of two or more fused aromatic rings (Yang and Silverman, 1988). Polycyclic aromatic hydrocarbons originated mainly from anthropogenic processes, particularly from incomplete combustion of organic fuels. Polycyclic aromatic hydrocarbons are distributed widely in the atmosphere. Natural processes, such as volcanic eruptions and forest fires, also contribute to an ambient existence of PAH. (King el al., 2002). PAHs can be present in both particulate and gaseous phases, depending upon their volatility. Light molecular weight PAHS that have two or three aromatic rings are emitted in the gaseous phase, while high molecular weight PAHS with five or more rings, are emitted in the particulate phase. In the atmosphere, PAHS can undergo photo-degradation and react with other pollutants, such as sulfur dioxide, Nitrogen oxides and Ozone (Ionne et al., 2007) Due to widespread sources and persistent characteristics, PAHS disperse through atmospheric transport and exist almost everywhere. Human beings are exposed to PAH mixtures in gaseous or particulate phases in ambient air. Long term exposure to high concentrations of PAHS is associated with adverse health problems, since some PAHS are considered carcinogens, inhalations of PAHS in particulates is a potentially serious health risk linked to an excess risk of lung cancer (Hassanien, 2008). Polycyclic aromatic hydrocarbons (PAHS) were as the ninth most threatening compounds to human health 2001 (Simko  et al, 2002). The carcinogenicity and mutagenicity of several compounds in this category is proved (Dickhut et al, 2000). Several epidemiological studies of PAHS especially among workers exposed to these compounds in a number of countries are carried out (Grimmer et al 1998). High molecular weight PAHS, i.e. PAHS with four or more condensed aromatic rings, are considered to be more dangerous than two and three ring PAHS in view of their higher genotoxic potentials.(Yang and Silverman, 1988). These compounds are ubiquitous in the environment, formed naturally by forest fires, volcanoes plants, fungi and bacteria or anthropogenically through the combustion of fossils fuels ( Hoffman  et al , 1985). It is conceivable that faster deposition of exhaust aerosol dropletsoccurs close to the high way, while further spreading mediates by their adsorbed form on the dust particles that are distributed with wind ( Tuhackova  et al, 2001), affected other media (e.g air, water, soil and plants). Therefore significant exposure risk for human, population is strongly expected (Abdel  et al, 2008).
