# Risk Elements in Total Suspended Particles in Areas Affected by Opencast Mining of Brown Coal
## 2 Materials and Methods
### Human Health Risk Assessment  
The average daily dose (ADD) for ingestion of the individual elements is calculated as follows:  
\[ADD=\frac{C\times IngR\times EF\times ED\times 10^{-6}}{BW\times AT} \tag{2}\]  
where \(C\) is TSP element content (mg/kg); \(IngR\) is the ingestion rate of soil (0.0001 and 0.0002 \(\mathrm{kg}\)/day for adults and children, respectively) [31]; \(EF\) represents the exposure frequency (350 days/year); \(ED\) is the exposure duration (6 years for children and 24 years for adults) [32]; \(BW\) is the body weight (20 kg for children and 60 kg for adults) [33]; and \(AT\) is the time over which the dose is averaged (365 \(\times\) 6 days for children and 365 \(\times\) 24 days for adults) [31]. All calculations were conducted according to [PERSON] et al. [34], [PERSON] et al. [35] (2019), and [PERSON] et al. [36]. An \(ADD\) is considered to be at a virtually safe level when it is less than \(10^{-6}\), low risk between \(10^{-6}\) and \(10^{-4}\), and at marginal safety when it exceeds \(10^{-4}\).  
For an assessment of the potential non-carcinogenic risk of the TSP-borne risk elements for humans, the hazard quotient (HQ) was calculated as follows [37]:  
\[HQ=\frac{ADD}{R_{f}D} \tag{3}\]  
\begin{table}
\begin{tabular}{l c c c c} \hline \hline
**Location** & **Sample No.** & **Latitude** & **Longitude** & **Altitude (m)** \\ \hline \multicolumn{5}{c}{Sokolov city area} \\ \hline Vresová & 1 & \(50^{\circ}15^{\prime}39.09^{\prime\prime}\) N & \(12^{\circ}42^{\prime}17.07^{\prime\prime}\) E & 487 \\ Vmitriov & 2 & \(50^{\circ}14^{\prime}2.34^{\prime\prime}\) N & \(12^{\circ}43^{\prime\prime}11.69^{\prime\prime}\) E & 474 \\ Sokolov, Skolni street & 3 & \(50^{\circ}116.77^{\prime\prime}\) N & \(12^{\circ}38^{\prime\prime}28.69^{\prime\prime}\) E & 419 \\ Sokolov, Slikova street & 4 & \(50^{\circ}10^{\prime}26.48^{\prime\prime}\) N & \(12^{\circ}38^{\prime\prime}32.24^{\prime\prime}\) E & 413 \\ Kralovske Porfiči & 5 & \(50^{\circ}114^{\prime}44.94^{\prime\prime}\) N & \(12^{\circ}40^{\prime}53.08^{\prime\prime}\) E & 404 \\ \hline \hline \multicolumn{5}{c}{Litvinov city area} \\ \hline Lom u & 6 & \(50^{\circ}35^{\prime}10.31^{\prime\prime}\) N & \(13^{\circ}40^{\prime}26.439^{\prime\prime}\) E & 264 \\ Mom u Mostu & 7 & \(50^{\circ}35^{\prime}37.68^{\prime\prime}\) N & \(13^{\circ}390^{\prime}25.76^{\prime\prime}\) E & 297 \\ Litvinov downtown & 8 & \(50^{\circ}35^{\prime}53.54^{\prime\prime}\) N & \(13^{\circ}36^{\prime}40.23^{\prime\prime}\) E & 318 \\ Litvinov-Janov & 9 & \(50^{\circ}35^{\prime}27.01^{\prime\prime}\) N & \(13^{\circ}34^{\prime}6.01^{\prime\prime}\) E & 306 \\ Horni Jiretin & 10 & \(50^{\circ}34^{\prime}32.12^{\prime\prime}\) N & \(13^{\circ}32^{\prime}20.36^{\prime\prime}\) E & 296 \\ \hline \hline \end{tabular}
\end{table}
Table 1: The locations of the sampling points.  
where \(ADD\) is the calculated average daily dose and \(R_{f}D\) is a reference dose. According to IRIS [38], a reference dose is the United States Environmental Protection Agency's maximum acceptable oral dose of a toxic substance, \"below which no adverse noncancer health effects should result from a lifetime of exposure\". The EPA defines an oral reference dose (abbreviated \(R_{f}D\)) as: \"An estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to the human population (including sensitive subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime\". The available estimated \(R_{f}D\)s for the oral uptake of the risk elements, and the sources of these data, are summarized in Supplementary Table S1. If the HQ level is less than or equal to 1, the potential hazard is considered negligible [39].