One of the most shocking claims about the conditions in Amazon warehouses is that workers are under so much pressure to perform that they feel forced to pee in plastic bottles instead of taking a bathroom break. But, in an unusually blunt response to a congressman on Twitter late Wednesday, Amazon said that the claims are all made up. In the initial tweet, Rep. Mark Pocan (D-WI) ridiculed the company for describing itself as a “progressive workplace,” with the congressman saying that cannot be true “when you union-bust & make workers urinate in water bottles.” The Amazon News account directly responded to Pocan, asking: “You don’t really believe the peeing in bottles thing, do you? If that were true, nobody would work for us.” The claim that Amazon warehouse staff pee in bottles was first made by journalist James Bloodworth, who went undercover as an Amazon worker in Britain for a book on low-wage work. The claim has also been made by union officials representing Amazon workers.