Update: This story was updated with comments from the company

Oregon sued the agricultural chemical giant Monsanto on Thursday, alleging the company withheld information about the toxic effects of its products for decades, leading to widespread contamination across the state and health risks for humans, plants and animals.

The lawsuit, filed by Attorney General Ellen Rosenblum in Multnomah County Circuit Court, seeks at least $100 million in damages and cites ongoing cleanup costs at the Portland Harbor Superfund site as one example of the tens of millions in public resources being spent in response to Monsanto's toxic products.

In a statement, the company called the lawsuit "baseless."

Oregon is just the latest entity to single out Monsanto for developing and producing polychlorinated biphenyls, commonly known as PCBs. The colorless compounds were in high demand for decades because of their utility. They were fire-retardant and used in paint products, electric devices and hydraulic oils until the federal government banned them in 1979. PCBs are one of several chemical pollutants found in sediment at the Portland Harbor.

Oregon's lawsuit, along with those filed by the state of Washington, eight West Coast cities including Portland and the Port of Portland in recent years, contends the company knew as early as 1937 that PCBs were extremely harmful.

"Monsanto knew decades before PCBs were banned that they were toxic to the environment, but they failed to disclose highly pertinent information," Rosenblum said in a statement. "And, now, Oregon is paying a big price as PCBs are being dredged up in river sediments and measured in the tissues of fish and wildlife throughout the state.

"PCBs are extremely hard to get rid of — and it will take significant time and resources to fully clean them up. It only makes sense that the manufacturer of these PCBs, Monsanto, help clean up this mess with dollars," Rosenblum said.

PCBs are particularly difficult to remove because they are passed through the food chain from smaller species to predators.

In a statement, Monsanto vice president for global strategy Scott Partridge said the company "voluntarily stopped producing PCBs more than 40 years ago and didn't use or dispose of any PCBs in the state of Oregon."

"Clean-up efforts are underway in Oregon with the full group of responsible parties under supervision of the EPA, and it's most important that everyone stay focused on that work," Partridge said. "This lawsuit is baseless and undermines the ongoing EPA cleanup efforts, and Monsanto will defend itself accordingly."

In previous lawsuits, the company argued that the suits targeted a past product that was "lawful and useful" for decades.

The company had more than $15 billion in net sales in 2017, according to its most recent annual report.

Rosenblum's lawsuit alleges the company created an internal team designed to deflect criticism in the 1960s about the chemicals while allowing millions of pounds of the compounds to be used annually.

"Today, Oregon bears the burden of Monsanto's decision to place profit above all else," the lawsuit stated. "The toxic legacy that Monsanto left Oregonians lives on, as PCBs persist in Oregon's lands, rivers, and waterways, in its sediments, soils, and in the bodies of animals and humans. It has caused harm to aquatic, marine, and avian species, and poses ongoing risks to the health of the people of the State of Oregon."

The Portland Superfund's cleanup plan, estimated at more than $1.05 billion, is expected to take 13 years to complete. Scott Pruitt, the U.S. Environmental Protection Agency's administrator, recently placed the 10-mile contaminated stretch of the Willamette River on a list of top priority projects. The list of potentially responsible polluters on the harbor includes some 14 public and private companies that have worked with the federal government on a cleanup plan for years.

According to the lawsuit, PCBs can cause "systemic toxic effects" for people and animals, and are specifically known to "seriously impair the endocrine, neurologic, and reproductive systems." The lawsuit states the compounds are "probable human carcinogens."

Both the Port of Portland and city of Portland lawsuits are still ongoing, according to attorneys involved with the cases, after judges rejected calls from the company to dismiss the suits.

This story will be updated.

-- Andrew Theen

atheen@oregonian.com

503-294-4026

@andrewtheen

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