Venue characteristics, ambient and breath air quality measures by location, August–October 2012, Toronto Waterpipe Study
| Measurements | Background (n=17) | On patios (n=5) | Indoors (n=12) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mean (SD) | Median | Minimum–maximum | Mean (SD) | Median | Minimum–maximum | Mean (SD) | Median | Minimum–maximum | |
| Number of patrons | – | – | – | 15.8 (4.4) | 15 | 9–26 | 24.5 (11.7) | 25 | 5–66 |
| Number of active hookahs | – | – | – | 3.9 (2.0) | 4 | 0–13 | 9.5 (6.6) | 9 | 0–27 |
| Volume (m3) for indoor or area (m2) for patio venues | – | – | – | 56.3 (63.3) | 13.8 | 6.9–139.1 | 481.1 (535.1) | 276 | 87.9–2039.1 |
| Active waterpipe density (per 100 m2 on patio or 100 m3 indoor) | – | – | – | 24 (19.4) | 31.2 | 1.6–43.0 | 3.8 (3.6) | 3.1 | 0.0–17.1 |
| Ambient air measures | |||||||||
| PM2.5 (µg/m3)† | 20.7 (23.7) | 13.0 | 3.0–295 | 80.5 (156.4) | 31.0 | 12.0–1711 | 1419.4 (2063.2)*** | 535 | 5.0–17221 |
| CO (ppm)† | 0.20 (0.78) | 0.0 | 0.0–7.5 | 0.5 (0.7) | 0.2 | 0.0–7.3 | 17.7 (20.9)*** | 11.8 | 0.0–120 |
| Nicotine (µg/m3)‡ | – | – | – | 0.6 (0.3) | 0.7 | 0.1–0.8 | 3.27 (2.71) | 2.74 | 0.20–7.91 |
| CO2 (ppm)† | 597.7 (327.9) | 489.0 | 415.0–2629 | 560.9 (81.4) | 546.0 | 477.0–1394 | 1144.5 (567.9)*** | 991.0 | 443–3549 |
| Temperature (°C)† | 16.3 (5.1) | 15.8 | 4.9–25.4 | 23.1 (3.2) | 23.9 | 16.9–27.7 | 23.2 (3.3)*** | 23.9 | 7.4–28.2 |
| RH (%)† | 56.5 (11.7) | 57.7 | 18.0–82.3 | 56.3 (11.4) | 50.3 | 39.3–78.1 | 46.1 (8.0)** | 48.4 | 24.3–74.4 |
| Breath CO (ppm)§ | 1.8 (0.4) | 2.0 | 1.0–2.5 | 2.4 (0.4) | 2.5 | 2.0–3.0 | 15.1 (21.0)* | 5.3 | 1.5–70.0 |
*p<0.05.
**p<0.001.
**p<0.0001.
†Mixed-model analysis was used to test the overall difference in ambient air measures among background, patio and indoor places.
‡t Test was used to test the difference in air-nicotine levels between patio and indoor places.
§Paired t test was used to test the difference in overall breath CO before entering and after exiting the venue for patio and indoor measures.
CO, carbon monoxide; RH, relative humidity.