# Heavy Metals in Urban Street Dust: Health Risk Assessment (Lublin City, E Poland)
## 4 Discussion
Another reason for the lack of correlation with traffic intensity may be the displacement of road pollutants by winds, which blow at an average speed of 2.75 m/s in Lublin [49]. The diversity of the speed and intensity of winds in the city may also be related to the tunnel effects and local differences in surface heating. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Cr** & **Cu** & **Ni** & **Zn** \\ Children 1  & \(6.1\times 10^{-2}\)-\(3.4\times 10^{-1}\) & \(2.7\times 10^{-3}\)-\(3.7\times 10^{-2}\) & \(3.3\times 10^{-3}\)-\(1.1\times 10^{-2}\) & \(5.3\times 10^{-3}\)-\(1\times 10^{-1}\) \\ Children 2  & \(5.5\times 10^{-2}\)-\(2.9\times 10^{-1}\) & \(3.1\times 10^{-3}\)-\(3.9\times 10^{-2}\) & \(5.9\times 10^{-2}\)-\(2.2\times 10^{-2}\) & \(9.5\times 10^{-4}\)-\(2.6\times 10^{-3}\) \\ Children—this study (mean) (2013/2018) & \(2.8\times 10^{-2}\)/\(3.5\times 10^{-2}\) & \(1.7\times 10^{-3}\)/\(1.3\times 10^{-3}\) & \(0.6\times 10^{-3}\)/\(0.4\times 10^{-3}\) & \(0.6\times 10^{-3}\)/\(0.5\times 10^{-3}\) \\ Children—this study (maximum) (2013/2018) & \(4.8\times 10^{-2}\)/\(6.5\times 10^{-2}\) & \(9\times 10^{-3}\)/\(1.3\times 10^{-3}\) & \(0.9\times 10^{-3}\)/\(0.8\times 10^{-3}\) & \(1.0\times 10^{-3}\)/\(1\times 10^{-3}\) \\ Adults 1  & \(4.4\times 10^{-2}\)-\(2.3\times 10^{-1}\) & \(5.5\times 10^{-4}\)-\(1.7\times 10^{-2}\) & \(2.2\times 10^{-3}\) & \(2.4\times 10^{-3}\)-\(4.9\times 10^{-2}\) \\ Adults 2  & \(3.7\times 10^{-2}\)-\(2.1\times 10^{-1}\) & \(1.4\times 10^{-3}\)-\(1.8\times 10^{-2}\) & \(3.6\times 10^{-3}\)-\(1.2\times 10^{-2}\) & \(4.3\times 10^{-4}\)-\(4.12\times 10^{-3}\) \\ Adults—this study (mean) (2013/2018) & \(1.3\times 10^{-2}\)/\(1.5\times 10^{-2}\) & \(3\times 10^{-3}\)/\(2.2\times 10^{-3}\) & \(0.3\times 10^{-3}\)/\(0.2\times 10^{-3}\) & \(1.1\times 10^{-3}\)/\(0.9\times 10^{-3}\) \\ Adults—this study (maximum) (2013/2018) & \(1.8\times 10^{-2}\)/\(3.4\times 10^{-3}\) & \(1.6\times 10^{-2}\)/\(0.5\times 10^{-2}\) & \(1.5\times 10^{-2}\)/\(0.3\times 10^{-3}\) & \(2.4\times 10^{-3}\)/\(1.6\times 10^{-3}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Comparison of hazard indices for Kraków, Wroclaw and Lublin. The conducted research has a practical application. It enables assessment of the spatial differentiation of health risk in the city. This, in turn, allows for appropriate spatial planning management on the city scale--for example, designating recreational areas for residents, in particular, playgrounds. Knowledge of the general layout of areas with high heavy metal concentrations can also be used when planning new housing developments. It can also be helpful in activities aimed at limiting the negative health effects of pollution of the urban environment. The collected information is particularly valuable because no monitoring studies are carried out on the content of heavy metals in soils, air and city waters. Future research should focus on a better understanding of the determinants of heavy metal content in road dust in medium-sized cities, as well as an accurate assessment of their concentration in all environmental components--air, soil and road dust.