From: PM2.5 metal exposures and nocturnal heart rate variability: a panel study of boilermaker construction workers
Characteristics
Mean ± SD
or n (%)
Male
26 (100)
Age (yrs)a
43 ± 11
Range
29 – 64
Race
White
21 (81)
Black
1 (4)
Hispanic
3 (12)
Asian
1(4)
Current Smoker
7 (26)
Hypertensive
5 (20)
Nightb rMSSD (msec)
Workdayc
30.3 ± 16.0
Non-workdayc
32.0 ± 16.0