Table 2.
Distribution of PM2.5, PM components, temperature, and relative humidity in the 28-day exposure window before the visits of NAS participants.
| Exposure (Unit) | Exposure window (days) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Same day | 7 | 14 | 21 | 28 | |||||||
| Mean (SD) | IQR | Mean (SD) | IQR | Mean (SD) | IQR | Mean (SD) | IQR | Mean (SD) | IQR | ||
| Air pollutant | PM2.5 (μg/m3) | 9.57 (6.31) | 6.84 | 9.23 (3.83) | 4.87 | 9.17 (3.34) | 4.35 | 9.22 (3.13) | 4.14 | 9.27 (3.08) | 4.09 |
| Na (μg/m3, 10−1) | 1.71 (1.28) | 1.46 | 1.70 (0.79) | 1.03 | 1.69 (0.65) | 0.90 | 1.70 (0.60) | 0.84 | 1.71 (0.57) | 0.82 | |
| S (μg/m3, 10−1) | 9.54 (8.76) | 7.63 | 9.08 (5.14) | 5.92 | 9.01 (4.39) | 5.39 | 9.09 (4.10) | 5.33 | 9.14 (4.02) | 5.18 | |
| Black carbon (μg/m3, 10−1) | 7.77 (4.18) | 5.28 | 6.84 (2.31) | 3.33 | 6.80 (2.02) | 2.97 | 6.79 (1.92) | 2.89 | 6.80 (1.86) | 2.92 | |
| Fe (μg/m3, 10−2) | 6.93 (3.83) | 4.01 | 6.27 (2.38) | 2.44 | 6.22 (2.11) | 2.19 | 6.18 (1.90) | 2.13 | 6.19 (1.79) | 2.10 | |
| Cu (μg/m3, 10−3) | 3.59 (2.85) | 3.04 | 3.37 (1.47) | 1.53 | 3.37 (1.12) | 1.16 | 3.35 (0.94) | 1.00 | 3.35 (0.85) | 0.91 | |
| Zn (μg/m3, 10−2) | 1.18 (1.24) | 0.85 | 1.06 (0.58) | 0.61 | 1.06 (0.50) | 0.56 | 1.06 (0.49) | 0.52 | 1.06 (0.47) | 0.51 | |
| Al (μg/m3, 10−2) | 4.60 (3.17) | 3.38 | 4.50 (2.74) | 2.48 | 4.51 (2.57) | 2.16 | 4.53 (2.41) | 2.10 | 4.55 (2.31) | 2.21 | |
| Si (μg/m3, 10−2) | 7.06 (5.40) | 4.91 | 6.79 (4.57) | 3.97 | 6.82 (4.36) | 3.68 | 6.83 (4.04) | 3.49 | 6.87 (3.83) | 3.32 | |
| Ca (μg/m3, 10−2) | 3.21 (1.81) | 1.82 | 2.90 (1.14) | 1.22 | 2.89 (0.92) | 0.98 | 2.90 (0.92) | 0.98 | 2.91 (0.87) | 0.98 | |
| Ti (μg/m3, 10−3) | 3.56 (2.77) | 2.44 | 3.32 (1.65) | 1.46 | 3.32 (1.43) | 1.37 | 3.30 (1.27) | 1.28 | 3.30 (1.17) | 1.22 | |
| Cl (μg/m3, 10−2) | 1.07 (4.48) | 0.33 | 1.39 (3.88) | 0.56 | 1.33 (2.79) | 0.86 | 1.33 (2.38) | 1.01 | 1.33 (2.17) | 1.05 | |
| K (μg/m3, 10−2) | 3.60 (2.56) | 2.08 | 3.90 (3.70) | 1.54 | 3.95 (2.88) | 1.37 | 3.92 (2.33) | 1.35 | 3.92 (2.03) | 1.28 | |
| V (μg/m3, 10−3) | 3.01 (3.47) | 3.36 | 2.98 (2.39) | 3.00 | 3.01 (2.30) | 3.09 | 3.04 (2.24) | 3.04 | 3.05 (2.18) | 3.02 | |
| Ni (μg/m3, 10−3) | 2.58 (3.43) | 2.63 | 2.57 (2.48) | 2.70 | 2.63 (2.50) | 2.68 | 2.67 (2.48) | 2.65 | 2.68 (2.41) | 2.53 | |
| Pb (μg/m3, 10−3) | 5.03 (3.19) | 4.09 | 5.11 (1.94) | 2.49 | 5.13 (1.71) | 2.04 | 5.14 (1.58) | 1.77 | 5.16 (1.52) | 1.90 | |
| Temperature (°C) | 13.01 (8.64) | 13.29 | 12.79 (8.04) | 12.94 | 12.77 (7.93) | 12.59 | 12.78 (7.90) | 12.86 | 12.81 (7.88) | 12.86 | |
| Relative humidity (%) | 67.82 (15.73) | 24.42 | 67.66 (9.00) | 12.70 | 67.69 (7.26) | 10.20 | 67.65 (6.45) | 8.92 | 67.67 (5.97) | 8.45 | |
PM, particulate matter; NAS, Normative Aging Study; SD = standard deviation; IQR = interquartile range