Estimated differences between CAFP and CA exposures for selected venous blood lipids measured at 3 h and 22 h post-exposure. The estimates are expressed as % point differences per 100 μg/m3 increase in PM concentration relative to pre-exposure level. Horizontal bars correspond to 95% confidence intervals. Only HDL cholesterol decreased significantly at both time points (p = 0.040 and 0.011, respectively). For abbreviations see text.