## 3 Results and Discussion
### Chronic Health Risk Assessment  
Health risks due to inhalation exposures to benzene and formaldehyde for the staff in all investigated buildings were considered by applying both models, i.e., non-carcinogenic health risk and cancer risk assessment, using the methodologies described in Section 2.5. The computed HQ for the non-carcinogenic health risks and LCR values are depicted in Tables 6 and 7, respectively. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{1}{c}{**Symptoms**} & \multirow{2}{*}{**Compounds**} & \multicolumn{2}{c}{**SBS Group**} & \multicolumn{2}{c}{**Non-SBS Group**} & \multirow{2}{*}{\(p\)**-Value**} \\ \cline{3-3} \multicolumn{1}{c}{**Group**} & & \multicolumn{1}{c}{**Mean**} & & & \\ \hline \multirow{9}{*}{Eye irritation} & NO\({}_{2}\) & 15.0 & 11.6 & 0.092 \({}^{*}\) \\  & Benzene & 17.4 & 12.5 & 0.008 \({}^{**}\) \\  & Toluene & 22.0 & 16.7 & 0.010 \({}^{**}\) \\  & Ethylbenzene & 1.6 & 2.1 & 0.048 \({}^{*}\) \\  & a-Pinene & 5.5 & 8.6 & 0.072 \({}^{*}\) \\  & Benzaldehyde & 0.9 & 0.8 & 0.006 \({}^{**}\) \\  & Hexaldehyde & 8.0 & 6.7 & 0.003 \({}^{**}\) \\ \hline \multirow{9}{*}{Respiratory} & Ozone & 1.8 & 2.7 & 0.029 \({}^{**}\) \\  & NO\({}_{2}\) & 15.3 & 11.6 & 0.044 \({}^{**}\) \\  & Toluene & 21.4 & 17.2 & 0.055 \({}^{*}\) \\  & Ethylbenzene & 1.71 & 1.95 & 0.037 \({}^{**}\) \\  & d-Limonene & 4.00 & 5.27 & 0.038 \({}^{**}\) \\  & Formaldehyde & 23.8 & 21.8 & 0.167 \\  & 2-butanone & 11.1 & 10.4 & 0.017 \({}^{**}\) \\ \hline \multirow{9}{*}{Heart} & NO\({}_{2}\) & 17.9 & 12.2 & 0.028 \({}^{**}\) \\  & Ethylbenzene & 1.5 & 1.9 & 0.100 \\  & Acetaldehyde & 22.2 & 17.7 & 0.116 \\  & 2-butanone & 11.4 & 10.5 & 0.074 \({}^{*}\) \\  & Hexaldehyde & 8.6 & 7.0 & 0.023 \({}^{**}\) \\ \hline \multirow{9}{*}{General} & Ozone & 2.0 & 2.7 & 0.055 \({}^{*}\) \\  & NO\({}_{2}\) & 14.6 & 11.3 & 0.039 \({}^{**}\) \\  & Benzene & 16.3 & 12.5 & 0.012 \({}^{**}\) \\  & Toluene & 20.47 & 17.02 & 0.148 \\  & Ethylbenzene & 1.76 & 1.98 & 0.039 \({}^{**}\) \\  & 1,2,4-TMB & 2.42 & 3.14 & 0.174 \\  & 2-butanone & 10.91 & 10.33 & 0.031 \({}^{**}\) \\  & Hexaldehyde & 7.57 & 6.79 & 0.031 \({}^{**}\) \\ \hline \multicolumn{1}{c}{Skin} & Toluene & 25.55 & 18.35 & 0.082 \({}^{*}\) \\ \hline \hline \end{tabular} Note: Mann-Whitney U test. \(p\)-values indicated with (\({}^{**}\)) are significant at 5% and with (\({}^{*}\)) are marginal significant at 10%.  
\end{table} 
Table 5: Differences in indoor concentrations (\(\mathrm{\SIUnitSymbolMicro m}^{3}\)) between SBS and non-SBS among symptom subgroups. As shown in Figures 9 and 10, in all monitored office buildings, the concentrations of formaldehyde were below the limit (CA\({}_{\text{HCHO}}\) < 100 \(\upmu\)g/m\({}^{3}\)) set by WHO [1]. On the other hand, concerning the benzene concentrations are concerned, only buildings 1 and 6 were within the acceptable range, building 5 was marginally above the permissible limits and all other buildings exceeded the recommended value of 5 \(\upmu\)g/m\({}^{3}\)[84] with a maximum value of 32.5 \(\upmu\)g/m\({}^{3}\). In particular, WHO considers benzene as a pollutant without a safe level [1]. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Building** & **Formaldehyde** & **Benzene** \\ \hline B1 & 2.7 & 0.8 \\ B2 & 1.5 & 10.8 \\ B3 & 3.1 & 4.3 \\ B4 & 1.1 & 4.6 \\ B5 & 3.9 & 1.9 \\ B6 & 3.7 & 1.3 \\ B7 & 2.2 & - \\ B8 & 1.8 & 3.7 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: HQ values in all buildings under investigation for formaldehyde and benzene. Figure 13: Differences in indoor concentrations (\(\upmu\)g/m\({}^{3}\)) between air quality parameters (satisfaction vs. dissatisfaction group). The HQ value computed for the study of the non-carcinogenic health risk was higher than unity in all buildings for the pollutants under consideration, suggesting that workers in those particular office buildings might experience health problems. Such problems could include eyes and upper airways sensory irritation, along with lung effects involving asthma and allergies [1].