Post-harvest losses of stored produce due to storage pests have been estimated at approximately 30%. Consequently, farmers rely on pesticides, whose long-term use affect the composition of the produce. This study determines the effect of aluminum phosphide pesticides on the proximate composition and mineral contents of farm produce and the level of pollution index prior. Cocoa and Kola nut samples were obtained from local farmers at Aba-Oyo, Akure, Ondo State, Nigeria. Proximate composition was determined using AOAC methods and mineral contents were evaluated by Flame Emission spectrophotometer and Atomic Absorption Spectrophotometer. The determination of theobromine, caffeine, and pesticide residues was done by GC-MS. There are considerable variations in moisture, ash, crude fat, crude protein, crude fibre, and carbohydrate contents of cocoa samples before and after preservation. Both samples contained high levels of calcium, magnesium, potassium, copper, sodium, and iron. Unpreserved cocoa contained theobromine content of 0.74 mg/g while the full tablet sample contained 0.29 mg/g. Similarly, unpreserved Kola nut contained high caffeine content of 0.24% while the full tablet preserved Kola nut contained 0.08%. Likewise, unpreserved cocoa had pesticide residue of 0.73 µg/kg, while the full tablet preserved cocoa had the highest (0.88 µg/kg). Unpreserved Kola nut had pesticide residue of 0.65 µg/kg, while the full tablet sample had 0.74 µg/kg. Unpreserved samples were highly polluted with organochlorine and other harmful pesticide groups than preserved samples. All values remained below the European Union safety limits. The findings emphasize the need to educate farmers on using approved pesticides within regulatory limits