Industrial meat processing is a messy, smelly, unsavory business, which is why it’s highly regulated. Once animals are slaughtered for processing, a team of sanitation workers come into facilities after hours to clean up. But where 30% of America’s meat production workers are foreign-born, the majority of sanitation workers are immigrants. The reason is economic: to keep costs low, profits high, and legal responsibility minimal for producers like Tyson, contractors do the dirty work — some of most dangerous industrial work in America — without workers’ comp insurance.

At Bloomberg Businessweek, Kartikay Mehrotra and Peter Waldman expose the dangerous conditions sanitation workers labor under. In addition to low pay and frequent amputations, many sanitation companies do their best to deny compensation to injured workers and dodge Federal safety inspectors. American meat is cheap for a reason, Workers’ lives are treated cheaply because employers know that the undocumented want to stay as low profile as possible.

Gilberto Gonzalez, a 47-year-old Guatemalan immigrant who has been cleaning poultry plants in Alabama for 11 years, says smaller plants and sanitation contractors ask few questions of undocumented hires and accept virtually any supposed proof of employment eligibility. “They have a way of working it out to get people on,” he says. (“Gonzalez” is a pseudonym he provided for this article in order to speak openly about his experiences as an undocumented sanitation worker.)

He lives with three of his sons in a decaying mobile home just outside Albertville on northeastern Alabama’s Sand Mountain, famous for its snake-handling preachers. He sent for each son separately in recent years. Just teenagers when they came, the boys paid smugglers $10,000 apiece to spirit them along the 2,300-mile trek from Guatemala through Mexico, across the Rio Grande, and on to Alabama, the last leg in the back of 18-wheel trucks. They’re still mostly invisible. They work at night, stay inside during the day, use back roads to avoid police, and never open the door for anyone they don’t know. Once, the family huddled inside as Immigration and Customs Enforcement agents snooped around the trailer park and knocked on their door for several minutes. “We just prayed to God, and they finally left,” Gonzalez says.

He works now at a Tyson plant, an employee of a large cleaning contractor called QSI, owned by the Vincit Group of Chattanooga, Tenn. (QSI and Packers say they use the federal E-Verify system to confirm employment authorization.) The work is good, as these things go. He’s still haunted, though, by his previous job. For about 15 months, he and his oldest son, who is 22 and identifies himself as Miguel, worked sanitation at a small processing plant called Farm Fresh Foods LLC in Guntersville, Ala. The facility is typical of the makeshift warehouses that dot the back roads of chicken country, picking up deboning work and other butchering jobs from the big poultry producers. Most operate on thin margins—bad news for workers, particularly the undocumented, who are always the most vulnerable to abuse.

Farm Fresh’s sanitation supervisor rode the cleaning crew without mercy, according to the Gonzalezes and other former colleagues, who filed a complaint with OSHA in 2016. They were forced to work at punishing speeds in ankle-deep water with floating fat and chicken guts. They were enclosed in poorly ventilated rooms with chlorinated cleaning products wafting in the air, severely limited in bathroom and water breaks. The chemical vapor caused heart-pounding insomnia, Miguel says. Several workers had to seek medical help. Workers who didn’t keep up the pace were moved to an extremely cold area of the plant as punishment.