Copyright © 2015 IJAIR, All right reserved 187 International Journal of Agriculture Innovations and Research Volume 4, Issue 1, ISSN (Online) 2319-1473 Pedelogical Properties of Three Sub-Urban Vegetable Gardens in Akwa Ibom State, Nigeria EnoAbasi Deborah Anwana Department of Botany & Ecological Studies, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria Email: e_anwana@yahoo.co.uk Felix Okpako Ogbemudia Department of Botany & Ecological Studies, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria Email: Femeg2005@yahoo.com Abstract – Vegetables form staple foods within most households in Akwa Ibom State. Consequently, due to increasing market and household demands vegetable gardens are ubiquitous across most rural and urban landscapes within the state. The present study was conducted to determine different soil characteristics within three sub- urban commercial vegetable gardens. In addition, presence of heavy metals was analyzed both in the soil and the vegetables grown within the three gardens. The three dominant leafy vegetables analysed include: Telfairia occidentalis Hook. F., Gnetum africanum Welw. and Talinum triangulare (Jacq.)Willd. Results obtained showed that the heavy metals concentration of the soil within the different vegetable garden locations were not significant (P = 0.05). Also, the level of the heavy metals in the leaves of the vegetables was low and did not exceed World Health Organisation permissible concentration range except for iron (180-832mg/kg). Observations made from this study, is indicative of little or no incidence of heavy metal loading, thus pollution levels are minimal within the environment. But, the high iron content could likely become a public health concern. However, the current value may be attributed to the geological profile of the area as no visible foundry/industry was noted around the study site. Invariably, consumption of vegetables from these gardens is reasonably safe and current practices of cultivation by the farmers should be encouraged. Keywords – Heavy Metals, Pollution, Public Health, Soil. I. INTRODUCTION Vegetables and fruits are generally known to be a good source of vitamins, minerals and fiber, and human beings are usually encouraged to consume them for the benefit of their health. However, these plants, depending on where they are planted and how they are handled after harvest, are known to contain some essential and toxic metals over a wide range of concentrations. This is due to the fact that most plants absorb metals from contaminated soil as well as from deposits on parts of the plants exposed to the air from polluted environments [1]. In the recent past, the increasing demand for food safety has stimulated research on the risk associated with the consumption of food items that have been contaminated by pesticides, heavy metals and toxins [2]. Plants accumulate these toxins in their tissues; including roots, stems, bark and leaves e.g. [3]-[5]. In turn, bio-accumulated toxins get bio-magnified across different trophic levels as plants act as primary producers within any ecosystem. Thus, humans as tertiary consumers are ultimately exposed to heavy metal poisoning if not early detected within the food chain [6]. In Akwa Ibom State, as in most rapidly urbanized state within Sub-Saharan Africa, scarcity of land suitable for commercial agricultural purposes is a grave issue, especially within and around the Capital City. It is general practice for farmers to either cultivate old dumpsites or use surface soils obtained from dumpsite as manure to enhance crop production; thus, increasing the risk of metal contamination and pollution. With the high demand for vegetable staples in the state and the evidence of metal accumulation in green leafy vegetables [6], it is critical that research on heavy metals is conducted periodically. In this light therefore, the overarching aim of the present research was to assess the heavy metal status of vegetables grown within three different commercial gardens in Ibesikpo Asutan in Akwa Ibom State, Nigeria. II. METHODS 2.1 Study Area: The study was conducted in three leafy vegetable gardens located in Ikot Ada Akpan village in Ibesikpo Asutan Local Government Area, Akwa Ibom State. The Local government and shares boundaries with Uyo Capital City, Uruan, Nsit Ibom, Nsit Atai and Nsit Ubium Local Government Areas [7]. 2.2 Plant Samples Collection: The leaves used in this study were harvested from mature plants cultivated in three different gardens in Ibesikpo Asutan L.G.A. These were;  Talinum triangulare (Jacq.)Willd. [Garden 1]  Gnetum africanum Welw. [Garden 2] and  Telfairia occidentalis Hook. F. [Garden 3] At each garden, a total of 63 (21 leaves per species) young, tender, fresh and equal sized leaves were harvested and brought to the laboratory for heavy metals assay. The harvested leaves were placed under running tap to wash off the dirt. The leaf samples in each of the groups were air dried to remove the moisture and water droplets simultaneously. They were then dried to constant weight in an oven maintained at 105ºC, and pulverized to fine powder using a laboratory grinder. The ground leaves were collected into well labeled polythene bags and placed in a desiccator. Three grammes of each sample were carefully weighed into clean platinum crucible and ashed at 450- 500ºC then cooled to room temperature in a desiccator. The ash was dissolved in 5ml of 20% hydrochloric acid and the solution was carefully transferred into a 100ml volumetric flask. The crucible was well rinsed with distilled water and transferred to the flask and made up to the mark with distilled water and shaken to mix well. The resulting sample solutions were then taken for the determination of the heavy metal Manuscript Processing Details (dd/mm/yyyy) : Received : 08/08/2015 | Accepted on : 18/08/2015 | Published : 27/08/2015