Abstract—Five vegetables (spinach, lettuce, cabbage, tomato, and onion) were freshly harvested from the Alau Dam and Gongulong agricultural areas for the determination of some organochlorine pesticide residues (o, p-DDE, p,p’-DDD, o,p’-DDD, p,p’-DDT, α-BHC, γ-BHC, metoxichlor, lindane, endosulfan dieldrin, and aldrin.) Soil samples were also collected at different depths for the determination of the above pesticides. Samples collection and preparation were conducted using standard procedures. The concentrations of all the pesticides in the soil and vegetable samples were determined using GC/MS SHIMADZU (GC-17A) equipped with electron capture detector (ECD). The highest concentration was that of p,p’-DDD (132.4±13.45μg/g) which was observed in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (2.34μg/g) was observed in the root of spinach. Similar trends were observed at the Gongulong agricultural area, with p,p’-DDD having the highest concentration of 153.23μg/g in the leaf of cabbage, while the lowest concentration was that of p,p’-DDT (12.45μg/g) which was observed in the root of spinach. α-BHC, γ-BHC, Methoxychlor, and lindane were detected in all the vegetable samples studied. The concentrations of all the pesticides in the soil samples were observed to be higher at a depth of 21-30cm, while the lowest concentrations were observed at a depth of 0-10cm. The concentrations of all the pesticides in the vegetables and soil samples from the two agricultural sites were observed to be at alarming levels, much higher than the maximum residue limits (MRLs) and acceptable daily intake values (ADIs) .The levels of the pesticides observed in the vegetables and soil samples investigated, are of such a magnitude that calls for special attention and laws to regulate the use and circulation of such chemicals. Routine monitoring of pesticide residues in these study areas is necessary for the prevention, control and reduction of environmental pollution, so as to minimize health risks. Keywords—Alau Dam, Gongulong, Organochlorine, Pesticide Residues, Soil, Vegetables. I. INTRODUCTION ESTICIDES is an extremely diverse group of substances with a wide potential for a variety of toxic effects. They can range in acute toxicity from being lethal at low doses, such as strychnine, to the relatively large quantities, such as sodium chloride, which is also edible in measured quantities. Pesticides J. C. Akan is with the Department of Chemistry, University of Maiduguri Nigeria (phone: +2348036000506; e-mail:joechemakan@yahoo.com). L. Jafiya,Z. M. Chellube, Z. Mohammed, and F.I. Abdulrahman are with the Department of Chemistry, University of Maiduguri, Nigeria (e-mail: ljafiya@yahoo.com, zchellube@yahoo.com, muhd.zakar@gmail.com, fannas7@yahoo.com). have helped to increase crop production by controlling the pests that destroy the crops. However, some of the pesticides have adversely affected the non-target species by inducing carcinogenic, tetratogenic, mutagenic, neuro-toxic effects as well as alterations of reproductive processes or functions in experimental animals and in man [1]. Like op-DDT have been able to modulate the endocrine system by augmenting the sex steroid burden and have therefore been termed as endocrine disrupters [2]. Pesticides have sustained the growth in food production and preservation, although, their increased usage for good reasons, in both the developed and in the developing countries, has resulted in contamination of food and the environment, through pesticide residues [3]. Environmental pollution by pesticides has been identified as one of the major environmental impacts of agriculture [4]. Parent compounds, as well as metabolites of pesticides have been identified in air [5], water [6] and soil [7]. Reference [8] reported on the many environmental chemicals which are carcinogenic and 90% of these chemicals were pesticide related. Some of the most commonly used insecticides like toxophene, DDT, aldrin and dieldrin were found to be both carcinogenic and mutagenic, while carbaryl, ethylene dibromide and parathion were mutagenic. The herbicide, nitrofen, and the fungicide, captan, also possess similar properties. Pesticides differ in their mode of action, uptake by the body, metabolism and elimination from the body and toxicity potential. Because of these differences, some pesticides show acute short term effects, while others tend to accumulate in the body and with time demonstrate sub-lethal adverse health effects. Many of these compounds also persist in the environment and bioaccumulate in the animal and human tissues [9]. The degradation and transformation of the non-persistent chemicals in the environment are dependent on their physicochemical properties, the environment in which they reside and the threshold levels of these chemicals in the environment. Non-persistent chemicals degradation and transformation processes do not always result in decreased activity or dilution of the parent compound, for the degraded or transformed products are at times more toxic, resulting in biomagnification of the toxicity of the parent compound. Plants obtain pesticide residues directly from application and indirectly by aerial drift, soil dust, volatilization and root uptake. Pesticides applied to the shoots of plants can migrate through the cuticular layer by two routes: a lipoid and aqueous Determination of Some Organochlorine Pesticide Residues in Vegetable and Soil Samples from Alau Dam and Gongulong Agricultural Sites, Borno State, North Eastern Nigeria Joseph Clement Akan, Lami Jafiya, Zaynab Muhammad Chellube, Zakari Mohammed, Fanna Inna Abdulrahman P World Academy of Science, Engineering and Technology International Journal of Environmental and Ecological Engineering Vol:8, No:4, 2014 325 International Scholarly and Scientific Research & Innovation 8(4) 2014 scholar.waset.org/1307-6892/9998072 International Science Index, Environmental and Ecological Engineering Vol:8, No:4, 2014 waset.org/Publication/9998072