Exposure to PM2.5, NOx, and O3 is strongly associated with preterm birth and low birth weight at term, (small for gestational age) even at levels significantly below the minimum recommended by the European Union.

A 2017 study based on data from the US EPA, reported 15,808 preterm births in 2010 could be attributed to PM2.5 at a cost of $5.09 billion, of which $760 million was spent for medical care.

A 2016 New York University study of over 3 million births in the 48 contiguous States estimated that 3.32% of all preterm births in 2010 were attributable to PM2.5 costing $760 million in medical care. Lost economic productivity reported another $4.33 billion in lost economic productivity (based on estimated reductions in IQ and estimated consequences for productivity over a lifetime). In total, researchers estimated that $5.09 billion in pre-term-birth related costs (medical care costs and lost economic productivity combined) could be attributed to PM2.5.

According to the March of Dimes, in 2007 the annual cost attributable to premature birth and low birth weight was an estimated $26.2 billion, which included $1.9 billion for labor and delivery, $611 million for early intervention services, $1.1 billion for special education services, and $5.7 billion for lost productivity.

Worldwide, study after study underscores the link between vehicular pollutants and preterm/low-weight births. In Europe, the U.S., Mexico, Korea, across the globe, researchers have found associations between PM, NOx, and O3 exposure in pregnancy and increased risk for adverse pregnancy outcomes. And the harm is substantial and cumulative: a large study of a homogeneous Lithuanian population reported a 25% increased risk for preterm birth per 10 μg/m3 increase in NO2 concentrations during the first trimester of gestation. The same study observed a 20% increase in preterm birth per 50-μg increase in ambient PM10 levels - outcomes consistent with data from the 2007-2010 Ohio birth records study.

Alarming Evidence: Autism Linked to PM & NOx

In the past decade, data from studies and meta-analyses have suggested increased incidence of autism spectrum disorder among babies born in locations with elevated traffic-related pollution. Teasing out confounding factors and applying advanced analytical tools, researchers have isolated disturbing patterns that both explain the variance between population studies and point to underlying biologic damage in the developing brain. For example, as reported in a Harvard study, exposure during the third trimester of gestation increases risk by almost 50% but not before or after.

Researchers have identified over 200 genetic variants that predispose affected fetuses to developing autism if exposed to triggering pollutants, including PM. Immunologists have identified a gene variation associated with maternal production of anti-brain autoantibodies in response to a developing fetus, increasing the likelihood of offspring diagnosed with autism. Insights like these help to explain why a majority of pregnancies do not result in autistic children despite PM exposure. They also make clear the need for more research and most important, better protection for our most vulnerable, our children.

Decades of research in urban centers all over the world, from Barcelona, to Tel Aviv, to Wuhan, China, have observed statistically significant associations between PM and NOx exposure and critical cardiac birth defects including atrial septal defects and atrial coarctation. Surgical intervention is required to correct these abnormalities to prevent progression to adult cardiac disease and complications such as stroke, hypertension, atrial fibrillation, and heart failure. Even after surgery, children with these congenital heart defects typically have elevated risk for adult cardiovacular disease and shortened lifespan.

Orofacial Birth Defects Linked to Prenatal Exposure to Fine Particulate Matter

For decades, study data has strongly suggested a link between PM 2.5 exposure during pregnancy and orofacial birth defects. (cleft palate/lip). The association was confirmed most recently in a 2017 analysis of National Birth Defects Prevention Network data on 4.7 million births, which found each 10µg/m 3 increase in PM 2.5 concentration was significantly associated with cleft palate alone (but not cleft lip).