California’s San Joaquin Valley is an agricultural powerhouse in the U.S., producing more than $17 billion a year in crops on some 7 million acres of fields.1 The region is also home to CAFO (concentrated animal feeding operation) animals, including cattle. At the valley’s largest feedlot, Harris Ranch, 100,000 cattle are packed in over a stretch of 800 acres.

While it’s no secret that California is saddled with a sizable problem of air pollution, many people picture urban traffic as the source of the area’s ever-present smog. Lesser known is the fact that, as news outlet Undark reported, trucks working for Harris Ranch drive a collective 6,000 miles a day just hauling food to CAFOs, releasing nitrogen oxides (NOx) along the way.

Once in the air, NOx reacts to form nitric acid, which combines with ammonia emissions from the CAFOs, to form ammonium nitrate. Ammonium nitrate, in turn, may account for up to half of the particulate pollution 2.5 (PM2.5) in the agricultural mecca’s air.2 PM2.5, or fine-particle pollution, is less than 2.5 micrometers in diameter and is responsible for reduced visibility as well as some of the worst health problems associated with air pollution.

These particulates can enter your lungs and bloodstream, leading to heart attacks, worsened heart and lung diseases, respiratory problems and aggravated asthma.3 It’s no coincidence that 1 in 6 children living in California’s Central Valley suffers from asthma, according to the California Air Resources Board, which notes:4

“California's unique climate makes us a leading agricultural producer, but some of the areas with the most productive farmland of the state also suffer from the worst air quality in the nation. This not only impacts crops, but also impacts public health.”

‘Cows Plus Cars’ Ruining California’s Air

Speaking to Undark, Steve Brown of the National Oceanic and Atmospheric Administration’s Earth System Research Laboratory broke down California’s air pollution problem by stating, “[It’s] cows plus cars.”5 Those at the root of the problem, like Harris Ranch, have little incentive to change.

Even In-N-Out, California’s popular fast food chain that advertises fresh, locally-sourced food, gets its meat from Harris Farms CAFO.6 Further, CAFOs even receive government backing that allows their polluting practices to continue.

Case in point: U.S. Environmental Protection Agency (EPA) administrator Andrew Wheeler signed a rule in November 2018 that would make CAFOs exempt from reporting animal waste emissions.

What’s more, Harris Ranch hasn’t taken even basic steps to curb air pollution, such as swapping out its diesel trucks for those powered by low-emission natural gas, even though the government would give them about $2 million to do so.7

California has put policies in place to reduce NOx pollution from fossil fuel sources, which has led to NOx declining by 9 percent a year in urban areas like Los Angeles, San Francisco and Sacramento.8

However, a study published in Science Advances revealed agriculture, and particularly agricultural soils treated with nitrogen fertilizer, to be a major source of NOx pollution in California, contributing 20 to 51 percent of the total NOx emissions in the state.9

“These soil NOx emissions are sourced to N [nitrogen] fertilizer applications in Central Valley croplands,” the researchers explained. “Where agriculture is an important source of NOx, strategies to reduce nonpoint emissions will need to incorporate soil management approaches and policies that are fundamentally different from fossil fuel sources.”10

Just how bad is the air pollution in California’s Central Valley, where 4 million people reside? According to the EPA, “the San Joaquin Valley has some of the nation’s worst air quality, failing to meet federal health standards for both ozone (smog) and particulate pollution.”11

It blames the pollution on “heavy truck traffic on I-5 and Highway 99; diesel-burning locomotives, tractors and irrigation pumps; and wood-burning stoves and fireplaces” — failing to mention agriculture, which appears to be the greatest polluter of all. NOx pollution, in particular, may be responsible for 1 in 8 premature deaths worldwide, along with being linked to cancer, birth defects, heart disease and asthma.12

California Dairy CAFOs Also Problematic

The San Joaquin Valley is also home to a large number of dairy CAFOs, which together produce 20 percent of U.S. milk, making California the No. 1 milk producer in the country.13 There are nearly 2 million milk cows in California, which produce over 3 billion gallons of milk — and 35 million tons of manure — annually.14 The nonprofit environmental research and advocacy organization Californians Against Waste noted:15

“Most of California's dairy farms are in the Central Valley, which suffers from both air and water pollution … researchers have also estimated that one cow can emit between 100 to 200 liters of methane per day.

This doesn't include the methane that continues to be generated through bacterial decomposition in waste storage lagoons. Methane gas is 25 times more powerful greenhouse gas than carbon dioxide.”

… The release of methane gas and the waste piles can cause major pollution problems … The decomposition of animal wastes in the dairy can cause methane and ammonia gases to be released into the atmosphere.

Methane contributes to greenhouse gases, which can lead to global warming, while ammonia can cause respiratory problems, as fine particulate matter formulates in the air. Dust generated from animal activity also causes respiratory diseases, such as asthma.”

Residents in the area complain of health problems, including migraines, from the contaminated air and say they’re unable to go outside during the summer due to the stench.16 When manure is stored in lagoons or applied to fields, ammonia can volatize into the air at the time of application, whereas additional emissions can be released later as the soil breaks down.

It’s a similar situation occurring elsewhere in the U.S. When a chicken CAFO in Kentucky was monitored for one year, more than 10 tons of ammonia were emitted into the air.17 Ammonia, which is formed when microbes digest nitrogen in manure, has a pungent odor and can lead to chemical burns, cough and chronic lung disease. Other toxic air pollutants commonly released by CAFOs include:18

• Hydrogen sulfide, which has a rotten egg odor and can cause inflammation of eye and respiratory tract membranes, loss of olfactory neurons and even death
• Methane, an odorless but highly flammable greenhouse gas
• Particulate matter, including particles from feed, bedding, dry manure, soil, animal dander and feathers, which can cause chronic bronchitis and respiratory symptoms, declines in lung function and organic dust toxic syndrome, a severe flu-like illness

How the Almond Industry Contributes to Polluted Air

California alone supports more than 12 percent of the U.S. food economy,19 which includes nearly 1 million acres of almond crops, supplying 80 percent of global demand.20

It’s not unusual for almond fields to measure PM2.5 levels upward of 142 micrograms per cubic meter of air, which is quadruple the standard set by the EPA. Most of the problem stems from dust created by the almond harvesting process, which makes up 15 percent of the PM2.5 in some areas.21

“Machines crawl through the plots of almond trees, shaking each one to force the almonds to drop. The nuts are then blown and swept into piles,” Undark reported. “The process kicks up massive clouds of dust and debris … Less dusty harvesting methods exist, but they require expensive investments in new machinery.”22

For two to three months a year, the almond harvest leaves trees, cars and homes coated in dust.23 Sometimes the plumes of dust are so thick that visibility is reduced on nearby roadways, necessitating warnings when harvests are taking place.

The EPA estimated that almond harvesting kicks up nearly 41 pounds of dust per acre,24 and each orchard may be harvested three times in a season, leading to copious amounts of pollution. For comparison, wheat harvesting raises closer to 6 pounds of dust per acre.

Oil Industry and Forest Fires Add to California’s Air Woes

Dense oil fields — up to 9,000 wells running on 10,000 acres at one location in Kern County, the worst county in the U.S. in terms of air quality25 — add to the pollution problems facing the state. According to Undark: 26

“Most of the light oil has already been tapped over the last century, so San Joaquin Valley oil wells tend to produce some of the thickest, dirtiest petroleum in the nation. To bring up the more viscous remaining oil, drillers burn natural gas to create steam, which they inject into the wells. This process, according to the state emissions inventory, accounts for roughly 4 percent of the valley’s particulate pollution.”

Forest fires, in particular those that have ravaged Northern California in 2018, only make California’s air that much deadlier. In November 2018, parts of California earned the dubious distinction of having the worst air quality worldwide due to wildfire smoke in the area.27

Taken together, the problem of CAFOs, almonds, oil and wildfires raise serious issues for air quality in the state year-round. The American Lung Association’s State of the Air 2018 report confirmed this, finding that over 35 million Californians — or 90 percent — reside in counties that received a failing grade for at least one pollutant.28

Californians Also Exposed to Pesticide Pollution

Aside from air quality, those living in agricultural regions must also deal with pesticide pollution, and this is true of those living in Salinas Valley, California, dubbed the world’s “salad bowl” because of its high production of greens, peppers, broccoli and a host of other vegetable crops.

The area is known for heavy spraying of organophosphate pesticides, leading to the CHAMACOS Study, which followed hundreds of pregnant women living in the region. The children were followed through age 12 to assess what impact the pesticides had on their development.29 It turns out the impact was quite dramatic, and mothers' exposure to organophosphates during pregnancy was associated with:30

• Shorter duration of pregnancy
• Poorer neonatal reflexes
• Lower IQ and poorer cognitive functioning in children
• Increased risk of attention problems in children

Regenerative Agriculture Is the Solution

While CAFOs degrade the ecosystems around them, causing air, water and soil pollution along the way, regenerative agriculture rebuilds them, in large part by increasing soil organic matter and soil biodiversity. According to the nonprofit Regeneration International:31

“Regenerative agriculture leads to healthy soil, capable of producing high quality, nutrient dense food while simultaneously improving, rather than degrading land, and ultimately leading to productive farms and healthy communities and economies.

It is a dynamic and holistic, incorporating permaculture and organic farming practices, including conservation tillage, cover crops, crop rotation, composting, mobile animal shelters and pasture cropping, to increase food production, farmers’ income and especially, topsoil.”

You can help shape the future of our food system and help reduce pollution by being mindful of your own choices. Be sure to look and ask for biodynamic certified produce, for example, and AGA (American Grassfed Association) certified grass fed animal products.

Also seek out organic produce and animal products whenever possible, and boycott the CAFO meat, dairy and poultry that is a major source of air and water pollution and soil degradation in California and worldwide.