Vehicle Emissions: What They Mean For Your Health

The growing number of cars on the roads may be bad for your health.

Recent studies performed at the University of San Diego measured air pollutants in vehicle emissions. Oxides of nitrogen (NO_x) and particulate matter (PM) were quantified in an assortment of vehicles at cold and warm engine temperatures. These are of particular interest because of their negative impacts on human health.

NO_x is an important air pollutant, not only because of its role in the production of the dangerous chemical ozone, but because of its harmful effects on human health. Like ozone, it too impairs lung function. It also contributes to smog and acid rain.

Particulate matter affects human lung function, as well as heart function. High levels of PM in the atmosphere have been associated with an increased number of heart attacks.

Both NO_x and PM are formed during high temperature burning and combustion engines. Efforts have been made to decrease NO_x levels with the use of catalytic converters. These were shown to decrease NO_x levels, however they only start working after the vehicle engine has reached operating temperature. PM production was found to increase in cars at higher engine temperatures.