Southern California has historically been
plagued by high levels of air pollution owing to
the presence of a large motor-vehicle fleet, numerous
industries, the largest seaport complex in
the United States, and a natural landscape that
traps polluted air over the Los Angeles basin.
With mounting scientific evidence of the adverse
health effects of air pollution, aggressive pollution-
reduction policies have been enacted. These
have included strategies to control pollution from
mobile and stationary sources, as well as fuel and
consumer-product reformulations. As a result, airpollution
levels have been trending downward over
the past several decades in southern California.
Southern California has historically beenplagued by high levels of air pollution owing tothe presence of a large motor-vehicle fleet, numerousindustries, the largest seaport complex inthe United States, and a natural landscape thattraps polluted air over the Los Angeles basin.With mounting scientific evidence of the adversehealth effects of air pollution, aggressive pollution-reduction policies have been enacted. Thesehave included strategies to control pollution frommobile and stationary sources, as well as fuel andconsumer-product reformulations. As a result, airpollutionlevels have been trending downward overthe past several decades in southern California.
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