Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Air Pollution Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran.
Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran; Center for Solid Waste Research, Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran.
Sci Total Environ. 2018 Dec 1;643:1216-1222. doi: 10.1016/j.scitotenv.2018.06.259. Epub 2018 Jul 4.
Some recent human and animal studies have suggested that air pollution may affect the central nervous system and contribute to neurodevelopmental outcomes, such as autism spectrum disorder (ASD). We aimed to investigate the association between long-term exposure to ambient air pollution and increased odds of ASD among 2 to 10-year-old children. We conducted a case-control study in Tehran, Iran. Cases were 134 children born between 2004 and 2012 diagnosed with ASD whose mothers were resident in Tehran during their pregnancy, and controls were 388 children without ASD randomly selected from public schools and kindergartens. Land-use regression models were used to estimate their annual mean exposure to ambient particulate matter with aerodynamic diameter ≤10 μm (PM), sulfur dioxide (SO), benzene, toluene, ethylbenzene, p-xylene, o-xylene, m-xylene (BTEX), and total BTEX. Logistic regression was used for the analyses and adjusted for possible confounding variables. The odds ratios per 1 unit increase in pollutants in the adjusted models were 1.00 (95% CI: 0.99, 1.01) for PM, 0.99 (95% CI: 0.99, 1.00) for SO, 0.96 (0.83, 1.11) for benzene, 1.00 (0.96, 1.04) for toluene, 0.95 (0.79, 1.16) for ethylbenzene, 1.00 (0.78, 1.27) for p-xylene, 1.09 (0.94, 1.27) for o-xylene, 1.01 (0.92, 1.12) for m-xylene, and 0.99 (0.97, 1.01) for total BTEX. We did not find the evidence of association between estimated annual mean exposure to abovementioned ambient air pollutants and increased odds of ASD in children. However, our findings might be due to some important limitations. Further research with better control of confounding variables, improved spatiotemporal exposure estimates, and inclusion of other important markers of air pollution is recommended.
一些最近的人体和动物研究表明，空气污染可能会影响中枢神经系统，并导致神经发育结果，例如自闭症谱系障碍（ASD）。我们旨在研究儿童 2 至 10 岁时长期暴露于环境空气污染与 ASD 风险增加之间的关联。我们在伊朗德黑兰进行了一项病例对照研究。病例为 134 名 2004 年至 2012 年期间出生的儿童，其母亲在怀孕期间居住在德黑兰，被诊断为 ASD；对照组为 388 名来自公立学校和幼儿园的无 ASD 的儿童。使用土地利用回归模型来估计他们每年平均暴露于空气动力学直径≤10μm 的环境颗粒物（PM）、二氧化硫（SO）、苯、甲苯、乙苯、对二甲苯、邻二甲苯、间二甲苯（BTEX）和总 BTEX。使用逻辑回归进行分析，并调整了可能的混杂变量。调整模型中污染物每增加 1 个单位，PM 的比值比为 1.00（95%CI：0.99，1.01），SO 为 0.99（95%CI：0.99，1.00），苯为 0.96（0.83，1.11），甲苯为 1.00（0.96，1.04），乙苯为 0.95（0.79，1.16），对二甲苯为 1.00（0.78，1.27），邻二甲苯为 1.09（0.94，1.27），间二甲苯为 1.01（0.92，1.12），总 BTEX 为 0.99（0.97，1.01）。我们没有发现上述环境空气污染物的年平均暴露量与儿童 ASD 风险增加之间存在关联的证据。然而，我们的研究结果可能是由于一些重要的局限性所致。建议进一步开展研究，更好地控制混杂变量，改善时空暴露估计，并纳入其他重要的空气污染标志物。
