Independent Sen. Bernie Sanders of Vermont announced Tuesday that he has launched a Senate investigation into Amazon pertaining to the corporate giant's labor practices, calling conditions at the company's warehouses "dangerous and illegal" in a letter to Amazon CEO Andy Jassy. 

The investigation is being spearheaded by the Senate Health, Education, Labor and Pensions Committee, or HELP, of which Sanders is chair — a position he has held since January.

"Today, I launched an investigation into Amazon's disastrous safety record," wrote Sanders on Twitter.

"Amazon is one of the most valuable companies in the world owned by Jeff Bezos, one of the richest men in the world. Amazon should be the safest place in America to work, not one of the most dangerous," he added.

The committee has also launched a website where current and former Amazon employees are encouraged to share stories of their workplace experiences while at the company. The submissions are confidential, assures the committee, and aim to help the Senate investigate "how the company fails to protect workers and evades responsibility for their necessary medical care."

"The company's quest for profits at all costs has led to unsafe physical environments, intense pressure to work at unsustainable rates, and inadequate medical attention for tens of thousands of Amazon workers every year," wrote Sanders in his letter.

"We've reviewed the letter and strongly disagree with Senator Sanders' assertions," said Amazon spokesperson Steve Kelly in a statement to CBS News — with an open invitation for Sanders to tour an Amazon facility.

Amazon has long been criticized for its alleged labor practices, with reports of workers urinating in bottles to avoid taking breaks dating back to 2021.

The company has also been plagued by strikes, Occupational Safety and Health Administration violations and rising workplace injury rates.

In 2022, Amazon employees "suffered more serious injuries than all other warehouse workers in the country combined" — despite the company only employing approximately a third of the country's warehouse workers, according to a press release from the HELP Committee. Amazon's "serious injury rate" is double the overall average of the warehousing industry, the release continues.

"We take the safety and health of our employees very seriously," Kelly said in the statement.

"There will always be ways to improve, but we're proud of the progress we've made which includes a 23% reduction in recordable injuries across our U.S. operations since 2019," Kelly added. "We've invested more than $1 billion into safety initiatives, projects, and programs in the last four years, and we'll continue investing and inventing in this area because nothing is more important than our employees' safety." 

Earlier this year, Sanders launched a similar investigation into Starbucks' labor practices amid ongoing store unionization.

In:
• Amazon
• United States Senate
• Jeff Bezos
• Bernie Sanders
• OSHA
• Strike
• Union

C Mandler is a social media producer and trending topics writer for CBS News, focusing on American politics and LGBTQ+ issues.