Health effects of long-term exposure to ultrafine particles around Schiphol airport

Background and aim: Studies have shown elevated concentrations of ultrafine particles (UFP) near airports. Little is known about the health effects of UFP, in particular from aviation (UFP-aviation). We evaluated the health effects of long-term exposure to UFP-aviation around Schiphol Airport, The Netherlands. Methods: We investigated a wide range of health outcomes, by linking modelled annual average residential concentrations of UFP-aviation to individual data from existing health registries and surveys. We conducted two longitudinal cohort studies, on mortality and incidence of medication use, and a cross-sectional study using survey data on self-reported health and lifestyle factors. The cohort studies included all residents of 31 municipalities in a 45x50 km area around Schiphol Airport (~1.3 million adults). Survey data was available for 90,880 adults. Effect estimates were adjusted for individual and neighborhood-level covariates and expressed per 3500 pts/cm3 (~p5-p95 increment across the three studies). We performed a number of sensitivity analyses to evaluate the robustness of the results, including adjustment for co-pollutants and noise. The combination of different databases and designs allowed us to evaluate consistency of the findings both within and across studies. Results: We found no clear or consistent associations between UFP-aviation and health outcomes related to general health, respiratory health, neurodegenerative disease, or mental health. For cardiovascular health, we found robust positive associations with incidence of medication use for heart disease [HR 1.03 (95%CI 1.00-1.05)] and mortality for arrhythmia [HR 1.08 (95%CI 0.98-1.02)], but not for incidence of medication use for hypertension or (total or other subclasses of) cardiovascular mortality. In the survey data, we found robust significant associations with prevalence of hypertension and self-reported heart attack and consistently elevated (non-significant) associations with self-reported stroke. Conclusions: Exposure to UFP from aviation around Schiphol Airport was associated with cardiovascular health outcomes. Keywords: ultrafine particles, aviation, air pollution, mortality, morbidity