# Exposure to NO\({}_{2}\) and PM\({}_{2.5}\) While Commuting: Utility of Low-Cost Sensor
## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Mode of Transport**} & \multirow{2}{*}{**Person**} & \multirow{2}{*}{**Location**} & \multicolumn{2}{c}{**Mean (Min-Max) Concentration**} & \multirow{2}{*}{**Mean (Min-Max) Dose, \(\mu\)g/km**} & \multirow{2}{*}{**References**} \\ \cline{4-5} \cline{5-6}  & & & **Pr1p, \(\mu\)g/m\({}^{3}\)** & & & \\ \cline{3-6}  & & & **PM2.5** & **NO2** & **PM2.5** & **NO2** \\ \hline \multirow{5}{*}{Adults} & \multirow{5}{*}{Glinvoice} & Heating: & Heating, & Male: & Male: & \\  & & 9.5 \(\pm\) 11.1 & 28.1 \(\pm\) 27.7 & 9.8 & 33.8 & \\  & & (2.0-45.5) & (0.1-87.8) & (0.5-195.7) & (0.03-610.8) & \\  & & Non-heating: & Non-heating: & Female: & Female: & \\  & & 12.1 \(\pm\) 24.0 & 22.7 \(\pm\) 20.3 & 19.8 & 58.7 & \\  & & (2.0-117.2) & (0.2-103.3) & (0.6–431.6) & (0.5–778.9) & \\ \hline \multirow{5}{*}{Adults} & Barcelona, Spain & \multirow{5}{*}{29\(\pm\)1.7} & \multirow{5}{*}{32.8 \(\ast\)} & \multirow{5}{*}{[23]} \\  & Hamilton, Canada & & & & 35.6 per 1 h & \\ \cline{1-1} \cline{5-6}  & Thesaionaliki, Greece & & & 2.18 \(\ast\) & \\ \cline{1-1} \cline{5-6}  & & Montreal, Canada & & & \\ \cline{1-1} \cline{5-6}  & & & & & \\ \cline{1-1} \cline{5-6}  & Adults & Montreal, Canada & & 120.94 & & \\ \cline{1-1} \cline{5-6}  & & & (56.13–197.21) & & 18.73 & [39] \\ \cline{1-1} \cline{5-6}  & & & 38.6 \(\pm\) 17.1 & & \\ \cline{1-1} \cline{5-6}  & Adults & Xi’an, China & (19.0-116.8) & & 7.4 \(\pm\) 5.0 & [40] \\ \cline{1-1} \cline{5-6}  & & Lisbon, Portugal & \(30.5\pm 9.0\) & & & \\ \cline{1-1} \cline{5-6}  & & & (20.7–61.6) & & 60 & [41] \\ \cline{1-1} \cline{5-6}  & & & 8.1 \(\pm\) 85 \(\pm\) 66 & & 8 h \(\pm\) 28.01 & \\ \cline{1-1} \cline{5-6}  & & & 11 h \(\pm\) 0.47 & & 11 h \(\pm\) 23.81 & \\ \cline{1-1} \cline{5-6}  & & & 14 h \(\pm\) 38 & & 14 h \(\pm\) 15.38 & [42] \\ \cline{1-1} \cline{5-6}  & & Portugal & 1730 h \(\pm\) 67 \(\pm\) 43 & & 1730 h \(\pm\) 25.23 & \\ \cline{1-1} \cline{5-6}  & & & 21 h \(\pm\) 65 \(\pm\) 26 & & 21 h \(\pm\) 13.04 & \\ \cline{1-1} \cline{5-6}  & & & Winter: 21.5 & Winter: 30.6 & & \\ \cline{1-1} \cline{5-6}  & & & Summer: 16.9 & Summer: 57.5 & 5.5 \(\ast\) & 12.8 \(\ast\) & [43] \\ \hline \multirow{5}{*}{Adults} & \multirow{5}{*}{Milan, Italy} & \multirow{5}{*}{N/A} & Female: & \multirow{5}{*}{[44]} \\  & & & & Winter: & \\ \cline{1-1} \cline{5-6}  & & & & 13.6–107.4 & & \\ \cline{1-1} \cline{5-6}  & & & & 6.2–70.2 \(\ast\) & & \\ \cline{1-1} \cline{5-6}  & & & & & \\ \cline{1-1} \cline{5-6}  & & & & & \\ \cline{1-1} \cline{5-6}  & & & & & & \\ \cline{1-1} \cline{5-6}  & & & & Winter: & \\ \cline{1-1} \cline{5-6}  & & & & 9.5–93.9 & & \\ \cline{1-1} \cline{5-6}  & & & & & 7.2–81.0 \(\ast\) & \\ \hline \multirow{5}{*}{Adults} & Salt Lake City, USA & \multirow{5}{*}{12.62} & \multirow{5}{*}{1.03} & \multirow{5}{*}{[45]} \\  & & USA & & & \\ \cline{1-1} \cline{5-6}  & & Mexico City & 42 & 10.59 & [46] \\ \hline \multirow{5}{*}{Adults} & \multirow{5}{*}{Vellore, India} & Morning 101 & \multirow{5}{*}{12–17} & \multirow{5}{*}{[47]} \\  & & & (61–149) & & \\ \cline{1-1} \cline{5-6}  & & Afternoon 92 & & & \\ \cline{1-1} \cline{5-6}  & & (62–122) & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Exposure concentration of PM\({}_{2.5}\) and NO\({}_{2}\), as well as the inhaled dose, during three modes of transport: bicycle, vehicle, and walking in different locations.