Table 6.
Statistical summaries of carbonyl compounds at different sites of the present study.
| Sites | Carbonyl compounds | Detection frequency | Mean (ppb) | S.D. (ppb) | Median (ppb) | Min (ppb) | Max (ppb) |
|---|---|---|---|---|---|---|---|
| YI (n = 80) |
Formaldehyde | 96% | 7.40 | 5.74 | 4.81 | N.D. | 26.93 |
| Acetaldehyde | 96% | 2.75 | 2.02 | 2.24 | N.D. | 9.89 | |
| Propionaldehyde | 60% | 0.29 | 0.40 | 0.18 | N.D. | 2.67 | |
| Methyl ethyl ketone | 74% | 2.57 | 3.73 | 1.06 | N.D. | 15.92 | |
| Butyraldehyde | 5% | 0.06 | 0.34 | N.D. | N.D. | 2.67 | |
| i-Valeraldehyde | 11% | 0.03 | 0.09 | N.D. | N.D. | 0.50 | |
| n-Valeraldehyde | 31% | 0.11 | 0.22 | N.D. | N.D. | 0.95 | |
|
| |||||||
| YR (n = 78) |
Formaldehyde | 99% | 8.06 | 6.27 | 5.88 | N.D. | 31.38 |
| Acetaldehyde | 97% | 3.43 | 3.05 | 2.10 | N.D. | 15.74 | |
| Propionaldehyde | 50% | 0.35 | 0.61 | 0.06 | N.D. | 2.97 | |
| Methyl ethyl ketone | 73% | 2.05 | 2.93 | 0.96 | N.D. | 13.73 | |
| Butyraldehyde | 29% | 0.56 | 1.25 | N.D. | N.D. | 6.08 | |
| i-Valeraldehyde | 12% | 0.03 | 0.10 | N.D. | N.D. | 0.46 | |
| n-Valeraldehyde | 26% | 0.05 | 0.11 | N.D. | N.D. | 0.48 | |
|
| |||||||
| GI (n = 79) |
Formaldehyde | 99% | 5.99 | 4.55 | 4.89 | N.D. | 30.52 |
| Acetaldehyde | 99% | 1.97 | 1.12 | 1.85 | N.D. | 5.35 | |
| Propionaldehyde | 44% | 0.14 | 0.18 | N.D. | N.D. | 0.64 | |
| Methyl ethyl ketone | 91% | 2.74 | 3.12 | 2.04 | N.D. | 20.56 | |
| Butyraldehyde | 4% | 0.02 | 0.08 | N.D. | N.D. | 0.51 | |
| i-Valeraldehyde | 8% | 0.02 | 0.06 | N.D. | N.D. | 0.39 | |
| n-Valeraldehyde | 28% | 0.07 | 0.13 | N.D. | N.D. | 0.54 | |
|
| |||||||
| GR (n = 80) |
Formaldehyde | 100% | 7.15 | 5.54 | 5.45 | 1.65 | 28.66 |
| Acetaldehyde | 100% | 2.23 | 1.68 | 1.86 | 0.13 | 12.44 | |
| Propionaldehyde | 34% | 0.17 | 0.47 | N.D. | N.D. | 3.92 | |
| Methyl ethyl ketone | 86% | 2.29 | 3.02 | 1.86 | N.D. | 22.34 | |
| Butyraldehyde | 1% | 0.01 | 0.05 | N.D. | N.D. | 0.44 | |
| i-Valeraldehyde | 4% | 0.01 | 0.06 | N.D. | N.D. | 0.40 | |
| n-Valeraldehyde | 11% | 0.03 | 0.08 | N.D. | N.D. | 0.37 | |
|
| |||||||
| SC (n = 80) |
Formaldehyde | 98% | 6.52 | 4.84 | 5.30 | N.D. | 25.81 |
| Acetaldehyde | 98% | 2.54 | 2.87 | 1.48 | N.D. | 18.38 | |
| Propionaldehyde | 38% | 0.21 | 0.43 | N.D. | N.D. | 2.91 | |
| Methyl ethyl ketone | 78% | 2.05 | 2.11 | 1.75 | N.D. | 8.59 | |
| Butyraldehyde | 10% | 0.10 | 0.43 | N.D. | N.D. | 2.77 | |
| i-Valeraldehyde | 5% | 0.03 | 0.15 | N.D. | N.D. | 0.84 | |
| n-Valeraldehyde | 18% | 0.05 | 0.12 | N.D. | N.D. | 0.58 | |
N.D.: not detected.