Table 2.
Summary statistics and Spearman’s correlation coefficients of PM2.5 metal components and meteorological measurements in the VA Normative Aging Study between November 14, 2000 and December 21, 2011.
| Summary Statistics | Spearman’s correlation coefficients | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean (SD) | Median (IQR) | V | Ni | Cu | Zn | Pb | PM2.5 | O3 | Temp | RH | |
| V (ng/m3) | 3.2 (2.9) | 2.4 (3.4) | 1.00 | 0.84 | 0.25 | 0.55 | 0.34 | 0.39 | 0.02 | −0.01 | 0.05 |
| Ni (ng/m3) | 2.9 (3.2) | 2.0 (3.1) | 1.00 | 0.28 | 0.59 | 0.32 | 0.33 | −0.04 | −0.14 | 0.06 | |
| Cu (ng/m3) | 3.7 (2.9) | 3.5 (3.5) | 1.00 | 0.28 | 0.20 | 0.24 | 0.01 | 0.10 | −0.13 | ||
| Zn (ng/m3) | 13.5 (13.1) | 10.6 (9.5) | 1.00 | 0.32 | 0.33 | −0.06 | −0.05 | 0.03 | |||
| Pb (ng/m3) | 5.7 (3.7) | 5.2 (4.1) | 1.00 | 0.28 | 0.03 | 0.01 | −0.01 | ||||
| PM2.5 (μg/m3) | 9.9 (6.4) | 8.2 (6.7) | 1.00 | 0.19 | 0.17 | 0.01 | |||||
| Ozone (μg/m3) | 54.0 (23.1) | 52.0 (27.0) | 1.00 | 0.34 | −0.09 | ||||||
| Temp (°C) | 10.5 (10.1) | 11.1 (16.2) | 1.00 | −0.09 | |||||||
| RH (%) | 61.9 (14.8) | 65.0 (19.1) | 1.00 | ||||||||
Abbreviations: SD - standard deviation; IQR-interquartile range; V- vanadium; Ni-nickel; Cu-copper; Zn- zinc; Pb-lead; PM2.5- fine particulate matter mass; O3-ozone; Temp-temperature; RH- relative humidity.