It is known that ultrafine particles (UFP, particles smaller than 0.1 μm) can penetrate deep into the lungs and potentially have adverse health effects. However, epidemiological data on the health effects of UFP is limited. Therefore, our objective was to test the hypothesis that exposure to UFPs is associated with respiratory health status and systemic inflammation among children aged 8 to 11 years.

We conducted a cross-sectional study among 655 children (43.3% male) attending 25 primary (elementary) schools in the Brisbane Metropolitan Area, Australia. Ultrafine particle number concentration (PNC) was measured at each school and modelled at homes using Land Use Regression to derive exposure estimates. Health outcomes were respiratory symptoms and diagnoses, measured by parent-completed questionnaire, spirometric lung function, exhaled nitric oxide (FeNO), and serum C reactive protein (CRP). Exposure-response models, adjusted for potential personal and environmental confounders measured at the individual, home and school level, were fitted using Bayesian methods.

PNC was not independently associated with respiratory symptoms, asthma diagnosis or spirometric lung function. However, PNC was positively associated with an increase in CRP (1.188-fold change per 1000 UFP cm⁻³ day/day (95% credible interval 1.077 to 1.299)) and an increase in FeNO among atopic participants (1.054 fold change per 1000 UFP cm⁻³ day/day (95% CrI 1.005 to 1.106)).

UFPs do not affect respiratory health outcomes in children but do have systemic effects, detected here in the form of a positive association with a biomarker for systemic inflammation. This is consistent with the known propensity of UFPs to penetrate deep into the lung and circulatory system.

众所周知，超细颗粒（UFP，小于0.1μm的颗粒）可以深入到肺部，并可能对健康产生不利影响。但是，关于UFP对健康的影响的流行病学数据有限。因此，我们的目的是检验8至11岁儿童暴露于UFP与呼吸系统健康状况和全身炎症相关的假设。

我们对澳大利亚布里斯班都会区25所小学（小学）的655名儿童（男性占43.3％）进行了横断面研究。在每所学校对超微粒子浓度（PNC）进行了测量，并使用土地利用回归法在房屋中进行建模，以得出暴露估计值。健康结局是通过父母填写的问卷，肺功能测定，呼出气一氧化氮（FeNO）和血清C反应蛋白（CRP）进行测量的呼吸道症状和诊断。使用贝叶斯方法拟合暴露响应模型，该模型针对在个人，家庭和学校一级测得的潜在个人和环境混杂因素进行了调整。

PNC与呼吸道症状，哮喘诊断或肺活量肺功能无关。但是，PNC与CRP的增加（每1000 UFP cm ^-3天/天1.118倍变化（95％可信区间1.077至1.299））和FeNO的增加（每1000 UFP 1.054倍变化）呈正相关。 cm ^-3天/天（95％CrI 1.005至1.106）。

UFP不会影响儿童的呼吸健康结果，但会产生全身性影响，此处以与全身性炎症生物标记物呈正相关的形式检测到。这与UFP深入肺部和循环系统的已知倾向一致。