Hot exhaust from “trucks” with a tailpipe causes sudden infant death.
There are more sudden infant deaths on polluted days, days with a two hour average background level of about 0.05 ppm of nitrogen dioxide. If you are behind a "truck" with a tailpipe at a stop light, it is likely to fill your car with a concentration thirty times greater than the background for a polluted day. I saw a "dually" blow hot nitrogen dioxide a few hundred times greater in the face of an infant in a stroller. This pickup with dual tires was turning right and accelerating full throttle to merge with faster moving traffic. Its tailpipe passed a few feet from the infant. Some infants do not survive such brutality.
The driver was oblivious to what he was doing to the infant and so was the mother. A doctor doing an autopsy would have been clueless too.
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