In a recent study that followed 132,256 children from birth to age five to ten, women exposed to nitric oxide during pregnancy were more likely to have a child with autism, (Lief Pagalan, Celeste Bickford, Whitney Weikum, Bruce Lanphear, Michael Brauer, Nancy Lanphear, Lillian E. Hanley, et al., "Association of Prenatal Exposure to Air Pollution With Autism Spectrum Disorder," JAMA Pediatrics epub (November 19, 2018): doi:10.1001/jamapediatrics.2018.3101). According to US Environmental Protection Agency, sources of nitric oxide include emissions from cars, trucks, buses, power plants and off-road equipment. Encouraging vehicles such as bicycles and electric cars can reduce this risk. When we buy gas, we pay not only with cash but also with our health.