There is no question that industrial agriculture is polluting the nation’s waterways, but huge factory farms are not the only culprits: Food processing plants also dump millions of pounds of toxic waste into rivers, lakes, and streams, according to an analysis released by Environment America, a national coalition of advocacy groups.

The report listed the top 15 water polluters in terms of volume but focused mostly on Tyson Foods, which processes 73 million pounds of beef, pork, and poultry every week.

“Tyson Foods Inc. and its subsidiaries dumped 104 million pounds of pollutants into waterways from 2010 to 2014,” the report said, citing the United States Environmental Protection Agency’s Toxic Release Inventory.

Of the 15 entities on the list, six are involved in food processing, including fourth-ranking Cargill (50.4 million pounds) and Perdue Farms (30 million pounds). Collectively, the six companies discharged 243 million pounds of waste, or 36 percent of the total.

“Over the years, we noticed that corporate agriculture is at or near the top of the list,” said John Rumpler, senior attorney at Environment America. Processing plants, he added, are the tip of the toxic iceberg when it comes to industrial agriculture.

“This doesn’t even begin to count the millions of tons of manure at factory farms,” Rumpler said. “The total pollution discharge, which is much larger than these self-reported direct discharge figures, do not get reported to EPA.”

Tyson’s direct discharges were second only to those of AK Steel Holding Corp., at 107.2 million pounds, and well ahead of the third-largest polluter, the U.S. Department of Defense, at 63.3 million pounds.

The sixth-largest polluter was oil-and-gas giant Koch Industries, with 34.2 million pounds. The company has spent millions to oppose environmental regulations and question global climate change.

At the bottom of the list was ExxonMobil, which discharged 15.3 million pounds, seven times less than Tyson.

The discharges, for the most part, are legal. Under the federal Clean Water Act, facilities can discharge toxic waste into waterways if they obtain a permit from the EPA.



“Most releases reported to and tracked by the TRI Program are permitted under other EPA programs,” an agency spokesperson wrote in an email.

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Tyson spokesperson Gary Mickelson said in an email that Environment America “is misinterpreting the information we regularly provide the EPA.”

“We vigorously refute these misleading claims by Environment America,” Mickelson said. “The water we use is returned to streams and rivers only after it’s been properly treated by wastewater treatment systems that are government regulated and permitted,” he said.

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But the EPA spokesperson confirmed that “Tyson-owned facilities reported releasing 104 million pounds of toxic chemicals in waste to surface water over the last five years.”

Almost all of Tyson’s releases were nitrate compounds, the EPA spokesperson said. Excess nitrates can lead to massive algal blooms that can choke waterways and kill huge numbers of fish. Blue-green algae releases gases that are harmful to humans.

High nitrate levels in drinking water can also cause “blue baby syndrome” in infants, which reduces the ability of blood to carry oxygen. Nitrates may also increase the risk of diabetes.

The EPA insists it is enforcing the law.

“EPA has taken a number of enforcement actions [against illegal discharges] in the last several years,” the agency spokesperson said.

Environmentalists contend the Clean Water Act is not being properly enforced.

Kelly Hunter Foster, senior attorney at Waterkeeper Alliance, said in an email that state and federal governments are mandated to control discharges, “but they are failing in nearly every way possible.”

The EPA has directed states to adopt limits on phosphorus and nitrogen discharges, but no state has applied them to all of its waters, while 27 states have not adopted any limits, Hunter Foster said.

“Because most states do not have these water-quality standards, Clean Water Act discharge permits end up being based on ‘technology based’ standards that are developed largely on cost without regard to the actual impact on water quality,” she said.

That means the toxic discharges will continue.

“It’s an awful lot of pollution,” Rumpler said. “If any of it is illegal, then someone needs to enforce the law. And if it’s legal, then those permits are obviously too weak.”