Association of household exposures with HONO levels in all homes with data
| N | Geometric mean HONO (ppb) | Unadjusted ratio of geometric mean (95% CI) | Adjusted* ratio of geometric mean (95% CI)(n = 234) | Adjusted† ratio of geometric means (95% CI)(n = 213) | |
|---|---|---|---|---|---|
| *Adjusted for all other factors in table. | |||||
| †Adjusted for all factors in the table plus indoor NO2 and outdoor NO2. | |||||
| Gas hob | |||||
| No | 103 | 2.05 | 1 (ref) | 1 (ref) | 1 (ref) |
| Yes | 149 | 4.05 | 1.97 (1.66 to 2.35) | 1.37 (1.12 to 1.68) | 1.26 (1.04 to 1.53) |
| Gas oven | |||||
| No | 159 | 2.33 | 1 (ref) | 1 (ref) | 1 (ref) |
| Yes | 92 | 5.03 | 2.16 (1.82 to 2.57) | 1.95 (1.59 to 2.41) | 1.62 (1.30 to 2.01) |
| Season | |||||
| Summer | 57 | 2.20 | 1 (ref) | 1 (ref) | 1 (ref) |
| Autumn | 86 | 3.15 | (1.15 to 1.88) | 1.55 (1.25 to 1.93) | 1.44 (1.16 to 1.79) |
| Winter | 35 | 4.09 | (1.39 to 2.59) | 2.09 (1.58 to 2.76) | 1.59 (1.19 to 2.12) |
| Spring | 74 | 3.42 | 1.58 (1.22 to 2.05) | 1.89 (1.51 to 2.38) | 1.65 (1.31 to 2.08) |
| Distance to street | |||||
| <20 m | 205 | 3.09 | 1 (ref) | 1 (ref) | 1 (ref) |
| ⩾20 m | 42 | 2.94 | 0.94 (0.73 to 1.22) | 1.01 (0.81 to 1.25) | 1.00 (0.81 to 1.22) |
| Buses and trucks pass in front of home | |||||
| No | 185 | 2.94 | 1 (ref) | 1 (ref) | 1 (ref) |
| Yes | 55 | 3.42 | 1.16 (0.92 to 1.47) | 1.17 (0.96 to 1.42) | 1.10 (0.92 to 1.32) |
| Smoking in kitchen during monitoring | |||||
| No | 209 | 3.03 | 1 (ref) | 1 (ref) | 1 (ref) |
| Yes | 34 | 3.25 | 1.06 (0.80 to 1.41) | 1.03 (0.82 to 1.30) | 1.06 (0.85 to 1.31) |
| Damp patches observed in bedroom or lounge | |||||
| No | 228 | 3.09 | 1 (ref) | 1 (ref) | 1 (ref) |
| Yes | 24 | 2.77 | 0.89 (0.65 to 1.23) | 0.82 (0.11 to 1.08) | 0.73 (0.60 to 0.94) |