Objectives To investigate changes in blood pressure, blood lipids, blood sugar and haematological markers of inflammation associated with changes in long-term exposure to ambient air pollutants.

Methods We conducted secondary analyses of data on blood pressure and blood biochemistry markers from the Social Environment and Biomarkers of Aging Study in Taiwan and air pollution data from the Taiwan Environmental Protection Administration in 2000. Associations of 1-year averaged criteria air pollutants (particulate matter with aerodynamic diameters <10 μm (PM₁₀) and <2.5 μm (PM_2.5), ozone (O₃), nitrogen dioxide (NO₂), sulfur dioxide and carbon monoxide) with systolic blood pressure, diastolic blood pressure, total cholesterol, triglycerides, high-density lipoprotein cholesterol, fasting glucose, haemoglobin A1c (HbA1c), interleukin 6 (IL-6) and neutrophils were explored by applying generalised additive models.

Results After controlling for potential confounders, we observed that increased 1-year averaged particulate air pollutants (PM₁₀ and PM_2.5) and NO₂ were associated with elevated blood pressure, total cholesterol, fasting glucose, HbA1c, IL-6 and neutrophils. Associations of increased 1-year averaged O₃ with elevated blood pressure, total cholesterol, fasting glucose, HbA1c and neutrophils were also observed. In particular, our two-pollutant models showed that PM_2.5 was more significantly associated with end-point variables than two gaseous pollutants, O₃ and NO₂.

Conclusions Changes in blood pressure, blood lipids, blood sugar and haematological markers of inflammation are associated with long-term exposure to ambient air pollutants. This might provide a link between air pollution and atherosclerotic cardiovascular diseases.