Children attending schools in the Tijuana communities of Colonia Chilpancingo and Colonia Campestre Murúa are exposed to high levels of diesel particulate matter, according to research conducted by Environmental Health Coalition and Colonia residents. Exposure to diesel exhaust is associated with serious health hazards including cancer, asthma and heart problems.

From December 2008 through April 2009, EHC and members of EHC's affiliate, the Colectivo Chilpancingo Pro Justicia Ambiental, conducted air quality sampling and traffic counting at three school sites – the communities' kindergarten, elementary school and high school. Analysis of the data showed that traffic volumes and ultrafine particulate levels are higher at the three school sites than at the control site.

Fifty percent of the trucks counted during sampling bore both U.S. and Mexican license plates, indicated they are licensed to operate on both sides of the border and are likely servicing the Maquiladora industry. Shortcuts past the schools save drivers time and fuel, but there are existing main arteries surrounding the neighborhood which are appropriate truck routes.

The community's conclusion that trucks needed to be banned from these streets was confirmed by a study conducted by Edgar Rodríguez of the San Diego State University Graduate School of Public Health. Working in cooperation with the Autonomous University of Baja California, he examined the relationship between roadside pollution and traffic counts to assess the potential exposure of these pollutants in elementary school children.

He concluded that high pollutant levels were present and justified re-routing commercial trucks away from residential neighborhoods and schools.

The community organized a successful petition campaign and trucks are now banned from the streets that pass the schools.