L.A.'s skyline shrowded in smog (Creative Commons).

Los Angeles County is one of the most-polluted counties in the U.S.

Recent studies identify Pacoima, Boyle Heights and Wilmington as toxic hotspots because of heavy pollution and other environmental hazards compared to other areas in the county. These three communities also have residential areas that are in close proximity to polluting sites, such as oil refineries, junk yards and freeways.

Studies demonstrate that many of these heavily polluted communities are also low-income communities of color.

Some environmental groups, such as Pacoima Beautiful and the California Environmental Justice Alliance, call this placement of residential areas adjacent to toxic sites neglectful city planning, and even environmental racism.

Now, local environmental groups and the L.A. City Council are advocating for businesses to use greener technology to lessen their burdern on the communities they neighbor. About two months ago, the L.A. City Council launched a campaign, called Clean Up Green Up, to encourage local businesses to implement cleaner technology practices.

So far, progress has been slow, and the city and these groups are still looking for funding.

Reach reporter Raquel Estupinan here.