Proximate Analysis and Polycyclic Aromatic Hydrocarbon Levels in Some Selected Raw Food Stuffs in Aroje and Owode, Nigeria.

Abstract

Some studies have shown that accumulation of polycyclic aromatic hydrocarbons (PAHs) in soil has the potential of contaminating the food chain. PAHs are complex organic compounds, many of which have been implicated for many health challenges. Information on the levels of PAHs in raw food in Nigeria is very scanty. Thus, an investigation into the levels of PAHs in some raw foods is of great importance from medical and environmental point of view. This study examined some proximate analysis parameters and levels of PAHs in raw cassava, yam, tomatoes, pineapple and maize and levels of PAHs in soil where these raw foods stuffs were collected. The samples were collected from two agrarian towns: Aroje and Owode in Oyo and Osun states, Nigeria. The proximate analysis was carried out according to the methods of Association of Official Agricultural Chemists (AOAC), while PAHs were determined using Gas chromatography-flame ionization detector (GC-FID). The results of proximate analysis for ash, moisture, protein, fat, fibre and carbohydrate ranged from 0.31-1.22%, 13.10-93.48%, 0.41- 9.00%, 0.27- 3.10%, 3.38-73.1% and 1.26-4.10% respectively. The concentration of total PAHs in the food samples are: Cassava (0.19571µg/Kg), Yam (0.15536 µg /kg), Tomatoes (0.02350 µg /kg), Pineapple (0.00753µg/kg) and maize (0.13718µg/kg) for Aroje and Cassava (0.20958µg/kg), Yam (0.16951µg/kg), Tomatoes (0.02408µg/kg), Pineapple (0.00752µg/kg) and Maize (0.13734µg/kg) for Owode. The average concentrations of total PAH in Aroje and Owode soils are 4.33583 and 4.37730 µg/kg respectively. The source diagnostic indices calculated showed that the PAHs in the samples were from pyrolytic source and there exists a correlation between some PAHS and total PAHS in the soil where the foodstuffs were cultivated.

Key words: Proximate Analysis, PAHs, Foods, Gas Chromatograph,