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Research May Show True Culprit Of Central Valley Smog

SACRAMENTO (CBS13) — California's Central Valley has some of the worst air quality in the nation, but it turns out we might have been wrong about the source of most smog.

Nitrous oxides, also known as NOx, have been found to be a major source of our pollution in Northern California as a result of fertilizer from agriculture. The molecule is the key component in creating smog which is very harmful to humans. It has been linked to respiratory disease, asthma, cardiovascular disease, and certain types of cancers.

The research says that fertilizer is responsible for up to 41 percent of NOx emissions. Much higher than previous studies showed.

"In California, it was an unrecognized source. So the farmers were not aware of it, people were not aware of it, and the state agencies were not really aware of this source of NOx," according to UC Davis Professor Benjamin Houlton.

Scientists took samples by air across California and found high levels from fertilized farmland. Even more so than other agricultural regions in the US because of our unique climate.

Dr. Maya Almaraz says, "We have a long growing season in California which means we can do several crop rotations in one year which means a lot of fertilizer added onto these hot, dry soils which can increase the production of NOx gas."

Scientists say their research can be used by lawmakers to help reduce smog and improve future air quality.

"The only way to tackle these environmental issues that involve agriculture is to work with farmers. It is really our hope to between the state, researchers, and farmers to come together and work proactively on the issues," says Dr. Almaraz.

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