SUNDAY, March 11 (HealthDay News) -- Gasoline engines produce
far more of a particular type of air pollution than diesel
engines, according to a new study. The researchers analyzed air
pollution in Los Angeles and were surprised to find that
gasoline engines were responsible for most secondary organic
aerosols (SOAs), which are tiny particles that can harm human
lung and heart health, reduce visibility and affect the climate.
The study confirmed that diesel trucks were used less on
weekends than on weekdays, while the use of gasoline-powered
vehicles remained nearly constant throughout the week. This led
the researchers to expect that weekend levels of SOAs would be
lower than weekday levels. Instead, the researchers found that
weekend and weekday levels of SOAs were about the same. This
means that gasoline engines are the main source of SOAs,
according to the study, slated for publication in the journal
Geophysical Research Letters. "The contribution of diesel to SOA
is almost negligible," study leader Roya