An undercover author told The Sun that workers at an Amazon warehouse in the UK "peed in bottles" because they were scared walking to a bathroom would cause them to miss targets.

The author, James Bloodworth, found that staff members feared being disciplined for "idle time."

A separate survey of Amazon workers released Monday found that some workers who reported feeling sick — even through pregnancy — said they were penalized for not turning up or taking breaks.

Amazon said it didn't recognize the allegations as an accurate portrayal of its warehouse working conditions.

The company disputed the survey findings and said it didn't time toilet breaks.

Amazon founder Jeff Bezos may be the world's richest person, with a net worth of about $112 billion (£78 billion), but at least some of those working on his warehouse floors are apparently so desperate to keep their jobs that they don't even take time to use a restroom.

The author James Bloodworth went undercover at an Amazon warehouse in Staffordshire, UK, for a book on low wages in Britain. He found that the warehouse's fulfillment workers, who run around Amazon's massive warehouses gathering products for delivery, had a "toilet bottle" system in place because the bathrooms were too sparse to get to quickly.

"For those of us who worked on the top floor, the closest toilets were down four flights of stairs," Bloodworth told The Sun. "People just peed in bottles because they lived in fear of being ­disciplined over 'idle time' and ­losing their jobs just because they needed the loo."

Amazon is known to track how fast its warehouse workers can pick and package items from its shelves, imposing strictly timed breaks and targets. It issues warning points for those who don't meet its goals or who take extended breaks.

A separate survey found almost three-quarters of UK fulfillment-center staff members were afraid of using the toilet because of time concerns. A report released Monday with the survey's findings said 241 Amazon warehouse employees in England were interviewed.

The survey anonymously quoted one person as saying targets had "increased dramatically" and "I do not drink water because I do not have time to go to the toilet."

Another said: "The target grows every year. I do not have two more legs yet to make the 100% to pick, where you actually need to run and go to the toilet just during the break. Packing 120 products per hour is terribly heavy.

"You have to pack two products per minute. You do not have time to drink water because you go to the toilet after every evening sends messages to the scanner with the target and tells you to hurry."

The survey, compiled by the worker campaign platform Organise, also found that respondents said they felt considerably more anxious after joining Amazon.

Workers say they have been punished for being sick

Another employee said she was ill while pregnant and was still given a warning.

And yet another said: "I turned up for my shift even though I felt like s---, managed 2 hours then I just could not do anymore. Told my supervisor and was signed off sick, I had a gastric bug (sickness and diarrhoea, very bad) saw my doc. Got a sick note with an explanation, but still got a strike."

Amazon disputed the allegations. The company said in a statement to Business Insider:

"Amazon provides a safe and positive workplace for thousands of people across the UK with competitive pay and benefits from day one. We have not been provided with confirmation that the people who completed the survey worked at Amazon and we don't recognize these allegations as an accurate portrayal of activities in our buildings.

"We have a focus on ensuring we provide a great environment for all our employees and last month Amazon was named by LinkedIn as the 7th most sought after place to work in the UK and ranked first place in the US. Amazon also offers public tours of its fulfillment centres so customers can see first-hand what happens after they click 'buy' on Amazon."

Amazon said it didn't time workers' toilet breaks and set its performance targets based on previous worker performance. The company said it provided coaching to help people improve and used "proper discretion" when it came to sick leave and absences from work.

The company also said it provided on-site occupational health and physiotherapy support as well as legal, financial, and workplace guidance.

If you worked in an Amazon warehouse and would like to share your horror stories, email in confidence to sghosh@businessinsider.com.