California Air Resources Board (CARB) has a collection of literally thousands of research papers from the peer reviewed scientific literature showing a very clear association between traffic associated air pollution (PM2.5) and just about every adverse health effect one can think of (COPD, asthma, pulmonary fibrosis, hypertension, CHF, heart attacks, diabetes, developmental delay, ADHD, dementia, seizures, Parkinsons disease, preterm labor, thyroid disease, obesity, various cancers). Would it not make sense to sue the automakers, similar to how the tobacco industry was sued?