Table 3.

Pearson’s correlation coefficients (r) between subject characteristics and deposition fraction (DF) of 20–30 nm particles of DEPs and deposited dose rate by mass

	DF 20–30 nm	Dose rate (mass)
FEV1	0.59*	−0.26
FEV1, % predicted	0.59*	−0.48
FEV1/FVC	0.79‡	−0.59*
FEV1/FVC, % predicted	0.79‡	−0.57*
FVC	0.47	−0.03
FVC, % predicted	0.42	−0.40
TLC	−0.32	0.65†
RV	−0.57*	0.54*
RV/TLC	−0.50*	0.30
PEF	0.60*	0.006
MEF50	0.58*	−0.46
MEF25	0.61†	−0.45
DLCO(SB)	0.39	−0.63*
DLCO/VA	0.61*	−0.81‡
DLCO/VA, % predicted	0.48*	−0.70†
Pack years	−0.60*	0.42
MV	−0.64†	0.77‡
f	−0.71†	0.28

*p < 0.05, ^†p < 0.01, ^‡p < 0.001.

Associations between DF and subject characteristics for all ultrafine particles (< 100 nm) were similar to 20–30 nm particles, but usually with a lower level of significance. No significant correlations were found for particles larger than 100 nm. DF and mass dose are averaged for diesel exhaust particles (DEPs) generated during both idling and transient driving.