Evaluation of Elemental Pollution in Roadside Dust Northeast of Nairobi Major Highway and at Thika Town, Kenya

Abstract

Aims: To evaluate the level of elemental pollution in roadside dust. Study Design: Dust samples were collected along Thika highway at Roysambu and at Thika town. Place and Duration of Study: Department of chemistry, government of Kenya laboratories, from July to December 2016. Methodology: Dust samples were collected at Roysambu bus terminal along Thika highway and at Kwame Nkruma road in Thika town. The samples were prepared for analysis according to USEPA method 3050B and analysis of Al, B, Na, Mn, Cr, Cu, Pb, Co, Mg, Fe, Ni, Ca and Zn in the samples was carried out using an inductively coupled plasma optical emission spectrophotometer. The results obtained showed that there was moderate pollution by Pb and Mn, while the samples were extremely polluted by B as computed using the index of geoaccumulation. Metals Cr, Mn, Pd and Zn were in levels similar to those reported around the world. Conclusion: These results showed that roadsides along the highway are more polluted than those inside the town, which is probably due to the high vehicular number. In addition, heavy metals may pose a health hazard to people exposed to roadside dust, which is not in line with the sustainable development goals (SDGs) 3 and 11.