Heavy Metals Content in Classroom Dust of Some Public Primary Schools in Metropolitan Lagos, Nigeria

This aim of the study is to determine the levels of heavy metals (Pb, Cr, Cd and Mn) in 40 dust samples obtained from the classrooms of some public primary schools in Lagos State, Nigeria. Children are more susceptible to the adverse health effects of heavy metal pollution due to their small body size, developing nervous system, high absorption rate and behavioral pattern present during childhood. Exposure to heavy metalladen dustis considered to be a significant contributor. To assess the extent of pollution by heavy metals, classroom dust samples were obtained from 40 selected schools in Lagos, Nigeria. The samples were subjected to aqua regia microwave digestion and analysed using graphite furnace atomic absorption spectrophotometer.The results showed that the classroom dusts contained PbHD 23.89±16.39, PbLD 22.77±9.21; CrHD 10.53±5.08, CrLD 6.17±2.47; CdHD 0.09±0.12, CdLD 0.09±0.10 μg/g, respectively. Interestingly, the highest concentration of lead (82.51 μg/g) was found in a classroom far removed from any commercial or industrial activites, Ajeromi-Ifelodun high density area while Ikeja, a more industrialized area has lower concentration of the metal. The values obtained in this study are lower than expected but it is still a source of concern since children are exposed to this environment daily and for appreciable period of time.