Values of different pollutants (mean (SD)) obtained in taxis and those recorded at the Paris air monitoring network fixed stations
| Taxis | Urban background | p Value | Close to motor vehicle traffic | p Value | High automobile traffic volume | p Value | |
| CO (ppm) | 3.8 (1.70) | 1.0 (0.46) | <0.0001 | 1.9 (0.56) | <0.0001 | 3.8 (1.0) | >0.05 |
| BS (μg/m3) | 168 (53) | 44 (29) | <0.0001 | 89 (24) | <0.0001 | 141 (47) | >0.05 |
| NO (μg/m3) | 625 (223) | 55 (30) | <0.0001 | 139 (30) | <0.0001 | 386 (74) | <0.0001 |
| NO2(μg/m3) | 139 (43) | 72 (22) | <0.0001 | 84 (22) | <0.0001 | 117 (19) | =0.01 |