MEXICO CITY -- The country's capital has spent the past decade cleaning up its environmental act with a series of policies aimed at reducing air pollution. But few other Mexican cities were following its lead.
Today, numerous metropolitan areas in Mexico -- none as big as the sprawling Valley of Mexico, or as notorious for smog -- have grown into the very same problem. Industrial, fast-growing cities like Monterrey, Guadalajara, Tijuana and Ciudad Juarez now face serious air pollution problems, say analysts.
But unlike Mexico City, these smaller big cities neither have the monitoring capabilities to inform the public when the air gets dangerously contaminated nor the public policies in place to do something about curbing emissions.
"It's not just a problem for Mexico City anymore," said Gabriela Alarcon, research director of urban development for the Mexican Institute for Competitiveness (IMCO).
"The rest of the country is headed in the opposite direction of the region and the world," which are working to reduce air pollution, she said. "We’re failing."
Since the 1990s, Mexico City has reduced peak concentrations of air pollution 60 percent through a series of efforts that have included closing dirty factories, placing restrictions on driving, and expanding and improving public transportation. Other cities in Latin America such as Bogota, Sao Paulo and Santiago have made similar strides, says Sergio Sanchez, executive director of the Washington, D.C.-based Clean Air Institute.
Although contamination levels are still high in these cities -- Mexico City's mountains frequently disappear behind a scrim of smog -- they prove that "these efforts can have a good result," Sanchez said by phone during a visit to Mexico City.
"It's a problem that we can manage," he said, "but we need to double or multiply the efforts."
Mexico's increasingly urban population is driving more, and a growing economy has spurred greater fuel consumption. Outside Mexico City, mass transit systems remain mostly outdated and unattractive to a rising middle class. Residents of mid-size cities opt for autos, a key source of the emissions that cause air pollution.
In urban zones, air pollution is one of Mexico's most pressing public health concerns, according to a report by a group of civil and academic organizations and the private sector called, "Toward Healthy and Competitive Cities: Promoting Clean Air."
The report cites alarming statistics: In 2010, nearly 15,000 Mexicans died due to illnesses associated with high concentrations of particulates in the air, according to the World Health Organization. Children are at special risk. Respiratory illness, including acute infections and asthma, is the third cause of death of children under four years in Mexcio, according to the country's health statistics agency.
Yet millions of people have no idea what they're breathing.
Just three cities do an adequate job of monitoring air quality, Alarcon said: Mexico City, Monterrey and Ciudad Juarez. Another 14 measure contamination but do so inadequately.
"The public perception of health risk is low," Alarcon said. "People don't know that they are exposed to air that could make them sick."
A new federal law, which takes effect in July, will require all cities with populations of 500,000 or more to monitor air quality. But cities will need follow-up training in the use and calibration of air monitoring equipment, Alarcon said, or "it could be yet another mandate that isn't met."
There are a few bright spots: About a dozen mid-size Mexican cities and regions have outlined plans to curb pollution as part of a federal program called ProAire, including Tijuana and Mexicali at the northern border and Puebla state in the country's central region. But, Sanchez says, it will be up to residents to hold their governments accountable to clearing their skies.
Photo of Monterrey, Mexico: Flickr/Roman Soto