Distinguishing Exposure to Secondhand and Thirdhand Tobacco Smoke and Electronic Cigarettes among U.S. Children based on Multiple Biomarker Profiles

项目摘要 三手烟是由老年人吸二手烟引起的一种明显的公共健康危害 被动吸烟后留下的，被表面、灰尘和家具吸收。多种有害毒物 在THS中包括与环境氧化剂反应的尼古丁（例如，亚硝酸）产生致癌物质 烟草特异性亚硝胺和烟草非特异性毒物如多环芳烃， 挥发性有机化合物电子烟（EC）气溶胶暴露是烟草特有的 有毒物质，尽管燃烧不会产生副产品。儿童最容易受到THS和EC的影响 气溶胶暴露及其相关影响。SHS和THS的组成不同，可以用 在不同烟草烟雾暴露（TSE）水平的儿童生物样本中， SHS和THS的累积暴露。区分非吸烟者THS和SHS的方法仅限于 评估自我报告、THS相关主要代谢物和NNAL与可替宁的比值。目前，没有黄金 标准TSE生物标志物，以区分暴露于THS与暴露于SHS或暴露于EC与暴露于THS。 可燃烟草制品我们的研究和其他研究表明，儿童TSE导致负面健康 结果和EC气雾剂暴露与哮喘症状有关。关键是要检查现有的烟草- 评估儿童暴露于各种烟草/尼古丁产品的特异性和非特异性生物标志物， 异质污染物这将提供对儿童TSE分类的深入了解，并解开相关 健康影响。因此，我们建议对国民健康和营养进行创新的二级分析， 2013-2016年考试调查数据。这个项目将是第一个检查流行率的项目， 的贡献，以及在假定未暴露于任何 烟草烟雾和儿童暴露于EC气溶胶。我们将检查多种生物标志物， SHS、THS和可能的EC气溶胶中的比例不同。将分析NHANES数据，以区分儿童TSE 组：1）混合SHS和THS组（MEG）：仅与不吸烟者或吸烟者一起生活， 报告的SHS; 2）主要THS组（TEG）：与非吸烟者或吸烟者一起生活，未报告SHS; 3） 主要EC组（ECG）：仅与EC使用者生活在一起，报告EC气溶胶暴露;以及4）无/极轻微 TSE组（NEG）：与非吸烟者一起生活，未报告SHS。首先，我们将比较烟草特异性生物标志物 数据与访谈数据，以验证自我报告和区分儿童到TSE组。然后，我们将使用 分类算法，以鉴定一组烟草特异性和非特异性生物标志物以及最佳的 区分TSE组。最后，TSE组与人口统计学和临床 和医疗保健利用模式将进行审查。产生结果的可能性， FDA-CTP是实质性的，因为儿童TSE生物标志物的使用是评估伤害水平的关键 目前尚不清楚这两种物质是否可归因于仅接触THS和仅接触EC气溶胶。

PROJECT SUMMARY Thirdhand smoke (THS) is a distinct public health hazard resulting from aged secondhand smoke (SHS) left behind from active smoking that absorbs into surfaces, dust, and furnishings. Multiple harmful toxicants are in THS including nicotine that reacts with ambient oxidants (e.g., nitrous acid) to create carcinogenic tobacco-specific nitrosamines and tobacco-nonspecific toxicants such as polycyclic aromatic hydrocarbons and volatile organic compounds. Electronic cigarette (EC) aerosol exposure is a source of tobacco-specific toxicants despite not generating by-products from combustion. Children are most vulnerable to THS and EC aerosol exposure and its related effects. SHS and THS differ in composition and can be assessed with biomarkers in biological samples of children with varying tobacco smoke exposure (TSE) levels, which is the cumulative exposure to SHS and THS. Methods to distinguish THS from SHS in nonsmokers are limited to assessing self-report, THS-related main metabolites and NNAL-to-cotinine ratios. Currently, there are no gold standard TSE biomarkers to differentiate exposure to THS from exposure to SHS or exposure to ECs from combustible tobacco products. Our research and others indicates child TSE results in negative health outcomes and EC aerosol exposure is linked with asthma symptoms. It is crucial to examine existing tobacco- specific and nonspecific biomarkers to assess children’s exposure to diverse tobacco/nicotine products and heterogeneous pollutants. This will provide insight on TSE classification in children and disentangle related health effects. Thus, we propose to conduct an innovative secondary analysis of National Health and Nutrition Examination Survey (NHANES) 2013-2016 data. This project will be the first to examine the prevalence, contributions, and health risks of exposure to SHS and THS among children presumed to be unexposed to any tobacco smoke and among children exposed to EC aerosol only. We will examine multiple biomarkers since proportions in SHS, THS, and likely EC aerosol, differ. NHANES data will be analyzed to distinguish child TSE groups: 1) Mixed SHS and THS group (MEG): lives with nonsmokers or smokers of combustible products only, reported SHS; 2) Predominant THS group (TEG): lives with nonsmokers or smokers, no reported SHS; 3) Predominant EC group (ECG): lives with EC only users, reported EC aerosol exposure; and 4) No/minimal TSE group (NEG): lives with nonsmokers, no reported SHS. First, we will compare tobacco-specific biomarker data with interview data to validate self-report and distinguish children into TSE groups. Then, we will use classification algorithms to identify a set of tobacco-specific and nonspecific biomarkers and ratios that best differentiates between TSE groups. Lastly, associations between TSE groups and demographics, and clinical and healthcare utilization patterns will be examined. The potential for generating results to inform the FDA-CTP is substantial as the use of child TSE biomarkers is key to assess the levels of harm attributable to exposure from THS only and EC aerosol only, which are currently unknown.