Joint effects of prenatal air pollutant exposure and maternal folic acid supplementation on risk of autism spectrum disorder

Abstract

We examined interactions between periconceptional folic acid (FA) and air pollution exposure on risk of ASD. Mothers exposed to higher levels of air pollution during the first trimester of pregnancy and who reported low supplemental FA intake during the first pregnancy month were at a higher ASD risk compared to mothers exposed to lower levels of air pollution and who reported high first month FA intake. Our results suggest that periconceptional FA intake may reduce ASD risk in those with high prenatal air pollution exposure.

Review and meta‐analysis found that prenatal folic acid was associated with a 58% reduction in autism but had no effect on mental and motor development

“…Finally, 16 papers with a combined cohort size of 756 365 children were considered in the present study: seven on mental development (12,14,19,20,24,34,35) and, or on motor development (14,19,20,24), and nine on ASD (17,18,23,(35)(36)(37)(38)(39)(40). As can be seen in Tables 1 and 2, two studies were RCTs (34,35), three were case-control studies (36,37,41) and the other 11 were from population-based cohorts (12,14,(17)(18)(19)(20)23,24,(38)(39)(40).…”

“…The studies were performed in Hungary (12,34,35), Germany (12), Greece (24), Poland (14), the United States (23,36,37,41), Norway (38,40), Denmark (17), Sweden (18), Israel (39) and Spain (12,19,20). The subjects' age at the time of evaluation ranged from 11 months to 15 years and was evenly distributed.…”

“…Most of the studies were of high (14,(17)(18)(19)(20)23,24,37) or moderate quality (12,36,37,41). Only two studies were of low quality (34,35) and probably had a high risk of selection bias, according to the Cochrane Collaboration's tool, because there was insufficient detail about sequence generation and allocation concealment.…”

Adequate Prenatal Maternal Folate—An Additional Intervention Strategy Among Populations Affected by Prenatal Lead Exposure?

“…It has been estimated that OWO affects nearly 2 billion people and that 62% of the population with obesity are from low-and middle-income countries. 5 7,8 Therefore, adequate folate intake might be used as prevention against the effects of air pollution in addition to policies that decrease exposure to these toxicants. These efforts could yield substantial public health benefits and represent novel tools in fighting the obesity epidemic.…”

The Unexpected Health Effects of Air Pollution

“…The periods of exposure to ambient air pollutants associated with autism were during pregnancy and in the 1st year of life. PM, TRAPs, and NO 2 appear to have the strongest effect on autism development, while ozone was linked to a modest increase in ADHD in a small number of studies, though there remains a need for more definitive studies [3][4][5][6][7]. Overall, PM 2.5 seemed to be the most important pollutant associated with Autism Spectrum Disorder (ASD), and perinatal exposure appears to be the most significant exposure period.…”