IOSR Journal Of Environmental Science, Toxicology And Food Technology (IOSR-JESTFT) e-ISSN: 2319-2402,p- ISSN: 2319-2399. Volume 5, Issue 1 (Jul. - Aug. 2013), PP 22-30 www.Iosrjournals.Org www.iosrjournals.org 22 | Page Physicochemical Parameters And Heavy Metal Analyses Of Water Samples From Hand Dug Wells In Gambari, Ogbomoso, Oyo State. 1* Adewoye S. O, 2 Adewoye A.O, 1 Opasola O.A and 3 Elegbede J.A 1 Department of Pure and Applied Biology,LadokeAkintola University of Technology, P.M.B 4000,Ogbomoso 2 Department of Earth Sciences,LadokeAkintolaUniversity of Technology, P.M.B 4000,Ogbomoso 3 Department of Sciences Laboratory Technology,LadokeAkintola University of Technology, P.M.B 4000,Ogbomoso Abstract: Some physicochemical characteristics and heavy metal levels in water samples obtained from twenty hand dug wells in Gambari, Ogbomoso, Oyo state, Nigeria were analysed in order to investigate and assess the drinking water quality. Conventional analytical methods were employed for the determination of the physicochemical parameters while heavy metals in the water samples were analysed using Atomic Absorption Spectrophotometer. The results of physicochemical parameters in the water analysed showed various ranges as follows: pH (5.57 -7.1, mean; 6.454), conductivity (225.67-1353μscm -1 , mean; 498.45 μscm -1 ), Alkalinity (0.43- 4.73 mg/L, mean; 1.27 mg/L), Total hardness (30.33-86.33 mg/L, mean; 44.92 mg/L), Dissolved oxygen (0.73- 7.5 mg/L, mean; 4.39 mg/L), Nitrates (0.00-5.0 mg/L, mean; 0.41 mg/L) and Sulphate (0.00-6.33 mg/L, mean; 0.34 mg/L). Also, from the results of the heavy metals analysed, high concentrations were recorded in certain wells especially in sample collected from GASP. The results indicated that the drinking water quality is becoming deteriorated because most of the water samples were found to be at minimum satisfactory level except for GASP (located within a cassava processing and milling industry) found to be at unsatisfactory level because ninety five percent of the parameters tested were found to be at high levels in concentration I. Introduction Much of the current concern with regards to environmental quality is focused on water because of its importance in maintaining the human health and health of the ecosystem (Mahanandaet al., 2010). Although water is the most common and important chemical compound on earth, only 2.6% of the global water is freshwater and consequently available as potential drinking water. Availability of sufficient volume of drinking water continues to present major problems worldwide to public health (Postel, 1997). The importance of water is underscored by the fact that many great civilizations in the past sprang up along or near water bodies (Karikari and Ansa-Asare, 2004). In most industrialized countries, drinking water is ranked as food, and high standards are set for its quality and safety (Ölmez and Kretzschmar, 2009). Pollution of water bodies are usually caused by chemical and microbial contaminants which leads to waterborne infections and diseases (USEPA, 1991). Therefore guidelines and legislation has stated that water suitable for drinking should contain some parameters including microorganisms only in low amounts that the risk for acquiring waterborne infections is below an acceptable limit (Zhao et al., 2009). Also, Rapid urbanization of rural areas, industrialization and population growth have been the major causes of stress on the environment leading to problems like human health problems, eutrophication and fish death, coral reef destruction, biodiversity loss, ozone layer depletion and climatic changes (Sadiq, 2002; Bay et al., 2003). Improper disposal of industrial effluents which is most common in major African urban and rural centres has led to heavy contamination of the available fresh water resources reducing the volume of safe agriculture, domestic, irrigation and drinking water. The study area; Gambari, Ogbomosho is one of the towns around Ogbomoso, Oyo state, Nigeria. Ogbomoso is one of the largest Nigerian cities having a population approximately 645,000 as of 1991 (Chernowet al., 1997) and estimated at 861,300 in 2007 (Encarta, 2009) and it is a commercial centre situated in an agricultural region producing yams, cassava, maize, and tobacco (Chernowet al., 1997). The major occupation of people in Gambariis agriculture with production of cassava products as one of the major products produced, since water is required in virtually all processing in agriculture, from the planting stage to harvesting and even to the stage of processing into edible forms (Omonona and Akinpelu, 2010), there is a need for a critical research on what the effects of usage of water for agricultural practices and its effluent disposal could have on the availability of quality water for the people. Therefore this study was carried out to investigate the impacts of selected pollution sources on the quality of water in hand dug wells in Gambari, Ogbomoso.