Low-paid workers producing clothes for Lululemon in Bangladesh say they endured physical abuse and regular humiliation from their managers, according to an investigation by the Guardian. One worker said she was violently slapped for leaving work early on a day when she was sick. Others described managers calling female workers “sluts” or “prostitutes,” as well as instances of physical abuse. A male worker said men at the factory were beaten and mistreated too. The workers also faced intense pressure to hit production targets that resulted in them working long hours without rest or breaks for meals.

The allegations, which Lululemon says it takes seriously and is examining, are sadly too common in the garment industry. Every so often, investigations by journalists or other watchdogs have turned up similar accounts from factories in low-wage countries making clothes for large international clothing companies. Frequently they’re the sort that sell large volumes of ultra-cheap clothes, resulting in a picture of worker abuse occurring in the supply chains of fast-fashion labels and other peddlers of incredibly inexpensive clothing.

But the allegations against Lululemon—a premium label built on sales of leggings that can cost well upwards of $100

—make clear labor abuses in clothing supply chains aren’t just a problem of fast fashion.

Earlier this year, the Ethical Trading Initiative, an alliance of companies, trade unions, and other organizations advocating for workers’s rights, released an in-depth report arguing the business model driving much of mass-market fashion contributes directly to the chronic abuses seen in the industry. This model relies on a dispersed—and consequently opaque—global supply chain to produce clothes at the greatest speed and lowest price possible, leading companies to low-wage countries in Southeast Asia and Latin America as they seek out factories offering the best mix of price, speed, and quality. It’s the reason Bangladesh, where the Guardian detailed the abuse allegations, has grown into the world’s second-largest garment exporter, and arguably why even a premium brand such as Lululemon produces most of its clothing in these regions (pdf).

The workers at the factory in Chittagong told the Guardian they could earn as little as 9,100 taka a month (about $107.50, or roughly the cost of one pair of Lululemon’s less-expensive leggings). The amount is higher than Bangladesh’s minimum of 8,000 taka a month for garment workers, yet still far less than the 16,000 taka some have demanded and activists say would constitute a living wage. To be as efficient as possible, and therefore make the most money for the factory, workers are also under great pressure to hit production numbers. At times these goals may hardly be achievable without them working extra hours or forgoing breaks for the bathroom or meals, as allegedly occurred in the factory supplying Lululemon.

AP Photo Thousands of Bangladeshi garment workers on the outskirts of Dhaka protested for better wages in January.

Issues of low pay and excessive hours don’t just crop up in developing regions. An investigation by the New York Times last year found home-based workers in Italy making garments for high-end brands. One woman said she earned wages well below what unions the Times spoke with considered acceptable and might work days as long as 18 hours.

Lululemon said in a statement the company is committed to a full investigation of the allegations at its supplier. “Members of lululemon’s social responsibility and production team visited the factory in Bangladesh immediately to speak with workers and learn more,” the company said. “We will work with an independent non-profit third party to fully investigate the matter. While our production at this factory is extremely limited, we will ensure workers are protected from any form of abuse and are treated fairly.”

A source close to the situation says the company has hired Impactt, an ethical trade consultancy, for the investigation. The person said Lululemon also intends to enlist other companies contracting with the factory to help remediate it.

It’s not clear at the moment which other brands have their clothes made at the factory. The Guardian identified it as being owned by Youngone Corporation, a large Korean firm that produces for a number of outdoor and sport brands. Adidas (xls) and Patagonia (pdf), for instance, both list Youngone factories in Chittagong as suppliers, though there’s no indication workers producing their clothes suffered any abuse. Yougone told the Guardian it’s committed to providing working environments that are safe and fair, and that it has launched an internal investigation.

The alleged abuse of mostly female workers looks bad for Lululemon, a company that markets wellbeing to a mostly female audience, even if allegations of this sort tend not to have long-term financial impact on companies, to judge from recent examples like H&M and Gap. Lululemon, meanwhile, says it assesses all its partners and has a Vendor Code of Ethics laying out how it expects them to operate. The company says it conducts annual audits of its largest suppliers and audits factories that do a small share of production for it at least every 18 months. The source close to the matter said the Lululemon is looking to understand the root causes that led to the worker abuses.