Heavy metals in dust are considered one of the most important environmental consequences of human activities. The objectives of this study are to investigate the ecological risk of heavy metals on human health in the dust of schools in Kut City, Iraq. The dust samples were collected from 25 primary schools and kindergartens. The pH, EC, TDS, and concentrations of heavy metals (Pb, Ni, Cr, Cd, Zn, Co, Mn) were measured. The heavy metals were analyzed using an atomic absorption spectrophotometer. The contamination factor (CF), enrichment factor (EF), and pollution load index (PLI) were calculated. The results showed that the mean concentration of Pb, Ni, Cr, Cd, Zn, Co, and Mn in the schools' dust were 37, 45, 60, 0.15, 73, 24, and 110 mg/kg, respectively. The mean concentration of all heavy metals was higher than the background concentration values of these metals, except for Mn and Ni. The highest amounts of Pb, Ni, and Cr were observed in schools 13, 7, and 1. The amounts of Cd were also significantly higher in schools 13, 7, and 23 than in other schools. The significant correlation between heavy metals shows that these metals have the same origin. The CF of most heavy metals was mainly in moderately contaminated (1 ≤ CF < 3). The EF for most elements was mainly in the class of significant enrichment (5 ≤ EF < 20). The PLI values ranged from 1.29 to 2.36, and 100% of the sampling fell into the polluted class.
Al-Mayah et al. (Wed,) studied this question.