Exposure to sub-chronic and long-term particulate air pollution and heart rate variability in an elderly cohort: the Normative Aging Study

Table 2 BC and PM_2.5 exposure distributions for Normative Aging Study participants^a

Pollutants (moving averages)	N visits	Mean (SD)	5^th–95^th percentiles	IQR
BC (μg/m³)
3 days	1161	0.43 (0.29)	0.12–0.93	0.29
7 days	1161	0.44 (0.26)	0.14–0.85	0.28
14 days	1160	0.44 (0.25)	0.14–0.81	0.26
21 days	1153	0.44 (0.24)	0.14–0.81	0.26
28 days	1148	0.44 (0.24)	0.15–0.81	0.26
1 year	974	0.45 (0.17)	0.22–0.74	0.19
PM_2.5 (μg/m³)
3 days	920	9.40 (4.48)	3.79–18.60	5.44
7 days	918	9.41 (3.32)	4.74–15.94	4.44
14 days	920	9.46 (2.91)	5.30–14.61	3.95
21 days	916	9.51 (2.67)	5.62–14.50	3.59
28 days	911	9.49 (2.53)	5.82–14.15	3.55
1 year	806	9.71 (1.36)	7.40–11.64	2.01

BC black carbon, IQR interquartile range, PM_2.5 particulate matter <2.5 μm in aerodynamic diameter, SD standard deviation
^aStudy visits with information on BC spanned 2000 and 2011. Study visits with information on PM_2.5 spanned 2003 and 2011

ISSN: 1476-069X