The Ohio senator Sherrod Brown had harsh criticism on Sunday for corporate lobbyists and Norfolk Southern, the Atlanta-based operator of the train that derailed in East Palestine, Ohio, two weeks ago while carrying toxic chemicals.

Speaking on Sunday to CNN’s State of the Union, the Democrat said the derailment, which released toxic chemicals including the carcinogenic vinyl chloride, was an episode of “the same old story”, and that Norfolk Southern “caused it”.

“Corporations do stock buybacks, they do big dividend checks, they lay off workers,” Brown said. “Thousands of workers have been laid off from Norfolk Southern. Then they don’t invest in safety rules and safety regulation, and this kind of thing happens. That’s why people in East Palestine are so upset.

“They know that corporate lobbyists have had far too much influence in our government and they see this as the result … These things are happening because these railroads are simply not investing the way they should in car safety and in the rail lines themselves.”

Brown said Norfolk Southern and corporate lobbyists were wholly responsible for the accident, which has caused breathing difficulties, rashes, nausea, headaches and swollen eyes, as well as killing pets and wildlife.

“There’s no question they caused it with this derailment because … they underinvested in their employees. They never look out for their workers. They never look out for their communities. They look out for stock buybacks and dividends. Something’s wrong with corporate America and something’s wrong with Congress and administrations listening too much to corporate lobbyists. And that’s got to change.”

On Tuesday, Norfolk Southern pledged to distribute more than $1.2m to nearly 900 families and a number of businesses affected by the crash, spill and burn. A company spokesman said the financial assistance included direct payments of $1,000.

Earlier this year, the company announced $10bn in stock buybacks. Last year, it reported $3.2bn in profits.

Brown warned residents along the Ohio and Pennsylvania border to be cautious.

According to Brown, the company “made promises” to him and the community. But he said: “If they write a check to an East Palestine or Unity Township resident or people even a little farther away, never sign away your legal rights. You can accept the check, but don’t sign anything that would sign away your legal rights. That’s what companies like this do.”

He added that he was going to make sure Norfolk Southern “lives up to everything it needs to do”.

Brown said he had urged Joe Biden and the US transportation secretary, Pete Buttigieg, to strengthen regulations surrounding worker safety, consumer protection and the environment.

“That’s my job, to push the administration and to move in Congress on … more pro-consumer, pro-worker, pro-environment … and pro-community safety laws to make sure these things don’t happen,” he said.

Republicans have criticized Buttigieg’s handling of the accident, arguing that the federal government has been too slow to respond.

In a tweet on Wednesday, Buttigieg said that the administration was restricted by certain laws on rail regulation.

“We’re constrained by law on some areas of rail regulation (like the braking rule withdrawn by the Trump administration in 2018 because of a law passed by Congress in 2015), but we are using the powers we do have to keep people safe,” he said.

That was a reference to to an Obama-era rule the Trump administration repealed, which required trains carrying highly flammable crude oil be equipped with special brakes to halt all cars at the same time.

Speaking to reporters, the Texas senator Ted Cruz, the ranking member on the Senate commerce, science and transportation committee, said: “I understand that the secretary is politically ambitious, and he’d like to move to government housing in Washington right up the street” – a reference to the White House, for which Buttigieg ran in 2020 – “but he does have a job to do.

Buttigieg, Cruz said, “should focus on addressing the enormous challenges we have on our railways, with multiple derailments where the secretary has been awol”.

The Ohio senator JD Vance and Marco Rubio of Florida wrote to Buttigieg, demanding “information from the US Department of Transportation regarding its oversight of the United States’ freight train system and, more generally, how it balances building a safe, resilient rail industry across our country in relation to building a hyper-efficient one with minimal direct human input”.