The mayors of Paris, Mexico City, Madrid, and Athens have pledged to ban diesel vehicles from their cities by 2025 in an effort to improve air quality.
The majority of vehicle pollution is produced by a small number of older or "badly-tuned" cars and trucks, according to a study by researchers at the University of Toronto in Canada.
California cities rank at the top of the list of the areas with the worst air pollution, according to the American Lung Association's "State of the Air" report for 2015.
One company that provides an alternative to idling big rigs at truckstops and truck terminals has plans for growth, including investing more money to fund a planned expansion.
The Port Authority of New York and New Jersey has approved the continuation of a program that helps port truckers replace older, higher-polluting vehicles with newer, cleaner burning ones.
Following the implementation of programs at the Port of Los Angeles to reduce emissions from trucks, ships, trains and other equipment, a new report shows the facility has made big strides in cutting back on air pollution.
The California Air Resources Board has fined the Los Angeles County Department of Public Works and DBI Beverage Inc. for environmental violations relating to their diesel fleets.