A lot of attention is paid to emissions from cars, but heavy-duty trucks represent a major part of the problem as well.
Trucks cover more mileage than the average passenger car every year, and with much worse fuel economy.
That's led the U.S. and Canada to tighten emissions standards for large trucks in recent years.
Now three environmental groups are urging Mexico to do the same.
The U.S.-based National Resources Defense Council (NRDC) joined with the International Council on Clean Transportation (ICCT) and Mexico's Centro Mexicano de Derecho Ambiental (CEMDA) to urge the Mexican government to update its standards.
The groups, along with the Boston-based Health Effects Institute, are pushing the government to pass a long-delayed set of emissions rules for trucks, said an NRDC press release (via Autoblog Green).
1992 Peterbilt 379 used to depict Optimus Prime’s vehicle mode in Transformers movies
They claim these rules could cut emissions of particulate matter and nitrogen oxides from trucks 90 percent.
This would help avoid 55,000 premature deaths, and yield more than $120 billion in net benefits, they claim.
But the groups claim that the new standard, called NOM-44, is in danger of being weakened by the government because of pressure from the industry.
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NOM-44 would require new trucks to have more emissions-control equipment like particulate filters, and boost fuel economy.
If passed, it would increase average new-truck costs by three percent, ICCT Senior Fellow Kate Blumberg said in a conference call Tuesday.
But the extra cost would be paid off in two years because of lower fuel consumption, she said.
Natural Gas-powered Kenworth truck (Image: Flickr user TruckPR)
The debate comes in the wake of Mexico's first smog alert in 11 years.
As part of a four-day alert earlier this month, the government banned more than one million vehicles from entering Mexico City, as ozone levels rose to twice the acceptable limits.
Transportation emissions already cause 20,000 premature deaths in Mexico per year, said Dan Greenbaum, president of the Health Effects Institute.
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Mexico has already pledged to cut emissions 22 percent from 1990 levels by 2030, as part of its commitment to the Paris climate-change agreement.
It has also established a peak year for emissions, 2026.
And the government wants a 50-percent cut in "black carbon" emissions—created by burning diesel, wood, and other fuels that produce particulates harmful to human health and cause immediate warming impacts.