Air Pollution Exposure during Pregnancy and Childhood Autistic Traits in Four European Population-Based Cohort Studies: The ESCAPE Project

Abstract

BackgroundPrenatal exposure to air pollutants has been suggested as a possible etiologic factor for the occurrence of autism spectrum disorder.ObjectivesWe aimed to assess whether prenatal air pollution exposure is associated with childhood autistic traits in the general population.MethodsOurs was a collaborative study of four European population-based birth/child cohorts—CATSS (Sweden), Generation R (the Netherlands), GASPII (Italy), and INMA (Spain). Nitrogen oxides (NO2, NOx) and particulate matter (PM) with diameters of ≤ 2.5 μm (PM2.5), ≤ 10 μm (PM10), and between 2.5 and 10 μm (PMcoarse), and PM2.5 absorbance were estimated for birth addresses by land-use regression models based on monitoring campaigns performed between 2008 and 2011. Levels were extrapolated back in time to exact pregnancy periods. We quantitatively assessed autistic traits when the child was between 4 and 10 years of age. Children were classified with autistic traits within the borderline/clinical range and within the clinical range using validated cut-offs. Adjusted cohort-specific effect estimates were combined using random-effects meta-analysis.ResultsA total of 8,079 children were included. Prenatal air pollution exposure was not associated with autistic traits within the borderline/clinical range (odds ratio = 0.94; 95% CI: 0.81, 1.10 per each 10-μg/m3 increase in NO2 pregnancy levels). Similar results were observed in the different cohorts, for the other pollutants, and in assessments of children with autistic traits within the clinical range or children with autistic traits as a quantitative score.ConclusionsPrenatal exposure to NO2 and PM was not associated with autistic traits in children from 4 to 10 years of age in four European population-based birth/child cohort studies.CitationGuxens M, Ghassabian A, Gong T, Garcia-Esteban R, Porta D, Giorgis-Allemand L, Almqvist C, Aranbarri A, Beelen R, Badaloni C, Cesaroni G, de Nazelle A, Estarlich M, Forastiere F, Forns J, Gehring U, Ibarluzea J, Jaddoe VW, Korek M, Lichtenstein P, Nieuwenhuijsen MJ, Rebagliato M, Slama R, Tiemeier H, Verhulst FC, Volk HE, Pershagen G, Brunekreef B, Sunyer J. 2016. Air pollution exposure during pregnancy and childhood autistic traits in four European population-based cohort studies: the ESCAPE Project. Environ Health Perspect 124:133–140; http://dx.doi.org/10.1289/ehp.1408483

Autism genes are selectively targeted by environmental pollutants including pesticides, heavy metals, bisphenol A, phthalates and many others in food, cosmetics or household products

“…Meta-analysis studies support the involvement of particulate matter or ambient air pollution in relation to autism in North American [81,309] but not European studies [87] and for the prenatal uses of SSRI's [310] or Vitamin D deficiency in autistic patients [311] but the diverse methodologies used to measure timing and exposure have rendered clear conclusions difficult for these and others such as phthalate esters [312]. These problems are confounded by the gene/environment interactions raised in this study (i.e.…”

Air Pollution and Neuropsychological Development: A Review of the Latest Evidence

“…An increased odds of ASD diagnosis was reported in Jung et al in relation to postnatal exposure to CO, NO 2 , O 3 , and SO 2 (40). However, 2 other studies in Europe encountered no association between prenatal exposure to NO 2 and PM 2.5 or PM 10 with autistic traits (41) or between pre-and postnatal exposure to NO x , PM 10 , and ASD (42).…”

ASD Validity

“…Boggess et al (2016) pooled heavy metals and organic pollutants into a single variable of xenobiotic exposure and reported that xenobiotic exposure level correlated with severity of ASD communication impairment (p = .02) and ASD social impairment severity (p = .05). Conversely, Guxens et al (2015) found no link between prenatal air pollution and ASD in a study of 8000 children. Volk et al (2014), however, demonstrated that if individuals homozygous for the C allele of the MET gene were exposed to air pollution, they had an increased ASD risk rate of 2.9 (1.0-10.6).…”