The Effect of Some Phosphate Fertilizers on the Contamination of Some Heavy Elements in the Soil and White Maize Plants

This research was carried out in the labs of the Soil Sciences and Water Resources Department at the College of Agriculture, University of Baghdad, over the 2024-2025 period. The goal was to investigate how certain phosphate fertilizers affect soil and white maize plants by contaminating them with heavy metals. We tested four widely used commercial fertilizers: Concentrated Superphosphate (CSP), NPK fertilizer (15-15-15), Diammonium Phosphate (DAP), and Rock Phosphate (R.P). The experiment followed a Completely Randomized Design (CRD) with three repeats per treatment, giving us a total of 12 experimental units. Our findings showed clear differences in contamination levels depending on the fertilizer. Rock Phosphate (RP) stood out with the highest levels of cadmium (140.77 mg kg⁻¹) and lead (221.60 mg kg⁻¹), making it the main culprit behind soil and plant pollution. The other fertilizers also showed varying degrees of contamination, and in some cases, heavy metal levels went beyond what’s allowed under international guidelines (USEPA, FAO, OECD, AAPFCO). These results underline the pressing need for tighter controls on the quality of phosphate fertilizers in farming to cut down on pollutant buildup in soil and crops, and to lower the environmental and health risks that might follow.