Every day crowded cells holding people at an immigration detention facility in Florida have been doused with caustic disinfectants that have caused breathing problems and bleeding, according to reports from the detainees. The disinfectants contain two chemical compounds that scientific research has implicated in long-term damage to human cells and—in animals—to reproductive health.

On August 26 a complaint filed on behalf of detainees at the Glades County Detention Center in Florida, which holds people for U.S. Immigration and Customs Enforcement (ICE), cited ongoing use of a “highly toxic chemical disinfectant,” sometimes multiple times per day, alongside “living conditions which are unsanitary, hostile, and unsafe.” The complaint was filed by several civil rights groups with ICE, the Department of Homeland Security (ICE’s parent agency) and the Glades County Sheriff’s Office. It is the second such complaint charging unsafe use of this type of disinfectant at the facility this year. Last year these same issues at Glades were also part of civil rights complaints and sworn testimony submitted for a lawsuit filed with the U.S. District Court for the Southern District of Florida.

Two disinfectants known to be sprayed at Glades are called Mint and Maxim Neutral, and their ingredients that have raised concern are known as quaternary ammonium compounds, or QACs. The disinfectants have been used because of fears of the spread of COVID at the Glades facility. Detainees have said that crews wearing backpack sprayers have showered these products into the air, contrary to both U.S. Environmental Protection Agency and manufacturer instructions, which state they should only be sprayed directly onto surfaces. And a Scientific American investigation has revealed internal e-mails that indicate Glades staff were not diluting at least one of these products to the highly reduced levels specified by its manufacturer’s EPA-regulated guidelines, adding to the danger. Both actions carry civil and criminal penalties under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). ICE declined to comment on any aspect of this story, citing “pending litigation on this subject.” The Glades County Sheriff’s Office also did not respond to a request for comment.

“The chemical is sprayed every day,” one person reported anonymously to a hotline run by the nonprofit Americans for Immigrant Justice (AI Justice). “Eyes burn. People cough.” Lily Hartmann, a human rights advocate at AI Justice, says that names of detainees in these complaints are often withheld to protect them from retaliation, including harassment and physical abuse. But one recent Glades detainee, Lunise Clerveaux, did go on the record in the August 26 complaint to say the spraying produced a “cloud” that “turns the air gray” as it lingers in the facility’s holding cells.

The Glades complaints echo those made by dozens of people held in other ICE detention centers, notably facilities in Adelanto, Calif., and Tacoma, Wash. Their statements are available in federal court filings, advocates’ direct complaints to the DHS and their partners and two EPA warning letters.

QAC Concerns

Research on the effects of QACs on humans published this year shows that cellular damage is worse among people with higher blood concentrations of QACs than among those with lower levels of exposure. And studies with human cells isolated in laboratories have indicated that QACs can disrupt a cellular process crucial to fetal development. Earlier research in mice linked exposures to the chemicals with long-term damage to reproductive and developmental health.

Mint and Maxim Neutral each contain two QACs: didecyl dimethyl ammonium chloride and alkyl-dimethyl benzyl ammonium chloride. They are among the most widely employed and cost-effective antimicrobials in use today. These two compounds are also in the disinfectant brand HDQ Neutral, which was used at the Adelanto ICE facility.

A warning letter released by the EPA in March stated that cleaning crews at Adelanto were spraying overconcentrated HDQ Neutral in the summer of 2020. The letter also said that detainees inhaled the spray, felt it hit their skin, and saw it fall onto their food and bedding. These practices and others repeatedly violated FIFRA across six misuse criteria, according to the EPA.

Manufacturers’ safety data sheets for QAC-based disinfectants clearly warn against inhaling them or allowing them to come into contact with the skin or eyes—and note that such exposure to the compounds can cause breathing problems, skin irritation or blindness, respectively. Further, “high vapor concentrations may cause central nervous system effects,” the Mint data sheet states, inducing symptoms such as headaches and dizziness.

The inhalation dangers are why spraying such a disinfectant around people is so bad even if the liquid solution is appropriately concentrated, says Kenneth Rosenman, a physician and chief of Michigan State University's division of occupational and environmental medicine. “Just think about it. If you spray something in the air, people are going to get it in their eyes, nasal membranes, breathe it in,” he says. “You shouldn't be doing that.”

Yet airborne spraying is exactly what detention facilities have been doing. This past July the EPA issued another warning letter to an ICE center in Tacoma, stating that the facility misused two more QAC-based disinfectant products, GS Neutral and Sani-T-10 Plus, again according to rules outlined in FIFRA. Less thoroughly documented cases in Colorado, Louisiana, and other states include detainees’ testimonies alleging symptoms that are consistent with acute QAC exposure, such as nosebleeds, vomiting and respiratory distress.

At Glades, the disinfectants were sprayed routinely, according to Jean Cleophat, a Haitian man who suffers from asthma and spoke with Scientific American via telephone in late February. At that time, he was 20 years old and had been detained at the facility since November 2020. “Sometimes, when I’m asleep at night, they’ve sprayed,” Cleophat said. “I’ll be waking up sweating. I can't breathe. I feel dizzy.”

In general, people have been using more QAC-based products during the pandemic amid the scramble to protect themselves from COVID. Homes in Indiana, for instance, showed a buildup of the chemicals, compared with prepandemic levels, according to a study last year by Amina Salamova, an environmental chemist at Indiana University Bloomington, and her colleagues. There have been reports of greater QAC contact among essential workers and commercial air travelers.

But at Glades, the chemicals have not just been used more often; they have also been sprayed at unusually high concentrations. In a March 12, 2020, e-mail obtained by Scientific American through a public records request, Chad Schipansky, commander of the detention division at Glades County, wrote to others at the Glades County Sheriff’s Office that the Mint disinfectant was so thick that it was “clogging up the backpack sprayer.” He directed personnel to “mix one gallon of the mint [sic] with a half gallon or so of water to thin it out a bit.” Yet a gallon of the chemical diluted with a half-gallon of water is still a much higher concentration than federal or industry requirements. An EPA public affairs adviser asked to review Schipansky’s memo responded that Mint “should be diluted at the rate of four ounces of product per gallon of water.” Those same dilution directions are printed on the Mint product fact sheet released to Scientific American with the Glades facility’s other public records.

Schipansky did not respond to requests for comment. An internal e-mail exchange between him and ICE officials from April 22, 2021, however, states that Glades began using Maxim Neutral disinfectant this year. It contains the same two QACs as Mint at comparable weight percentages.

From Mice to Humans

For decades, toxicologists thought that mammals (humans and rodents alike) do not absorb QACs or easily break them down, largely based on oral dosage trials with rats. But beginning in 2014, studies by geneticist Patricia Hunt of Washington State University and toxicologist Terry Hrubec of Virginia Tech started to show in animals that these compounds not only were absorbed but tended to linger inside the body. The scientists demonstrated that the severity of exposure to QACs tracks closely in the lab with neural tube defects in fetal mice and reproductive health issues in adult mice. Further mouse research suggested that QACs can accumulate inside the brain, liver and testes. These buildups concern Hunt and Hrubec, who theorize that the very feature of QACs’ molecular geometry that makes them effective at killing microbes—a long carbon chain that clings to fatty cell membranes and then disrupts them—also elevates their ability to accumulate as a toxin in any organism.

Human tissue has also shown evidence of bioaccumulation. Metabolomics researcher Oliver Fiehn of the University of California, Davis, Genome Center is a member of California’s environmental biomonitoring advisory panel, which tracks QAC usage. He analyzes 25,000 to 35,000 human blood, tissue and urine samples each year. In unpublished data, his group has found what he describes as a “highly surprising” three to five different QAC compounds in roughly 10 to 20 percent of these samples.

In March Hrubec and her team published a study that supports Fiehn’s observations. The scientists took blood samples from 43 volunteers recruited from the area around Blacksburg, Va., the home of Virginia Tech’s main campus. There were QACs in 80 percent of the participants’ blood samples. Blood cells in the samples showed inhibited function and signs of inflammation. The damage level increased with the amount of detected chemicals. More than one third of participants’ blood samples had QAC concentrations above the threshold shown, in the March study, to trigger this kind of damage. And at least two of the volunteers had QAC concentrations that appeared to be at or above limits set by the EPA, based on a 2006 federal standard for inhalation exposure to one of these chemicals.

“That’s an actionable level by the EPA,” says Gino Cortopassi, a toxicologist at U.C. Davis and a co-author of the March study. Beyond FIFRA penalties for negligent end users, EPA actions could include fining QAC manufacturers. Such penalties can be as high as $32,500 per day of inaction after a manufacturer becomes aware of the potential danger under the reporting requirements of the Toxic Substances Control Act.

Biochemist Libin Xu of the University of Washington has done test-tube studies with human cells that show QACs can disrupt the biosynthesis of cholesterol, which is essential to embryonic and fetal development. He agrees with Cortopassi that the QAC concentrations in the Blacksburg-area study would meet the EPA’s standard for intervention.

Some industry-supported scientists think QAC fears are overblown, however. Toxicologist Keith Hostetler of the company Toxicology Regulatory Services, whose clients include members of the specialty chemicals industry, says the compounds’ presence in human blood “doesn't ring any alarm bells.” He says that nearly all QACs present in the blood would quickly become “tightly bound to plasma protein before they are eventually removed from the system.” Hostetler did not cite any studies supporting this idea when asked to do so in follow-up e-mails.

Hrubec’s human blood concentration study might soon receive additional corroboration from Salamova and her colleagues at Indiana University Bloomington. In research currently undergoing peer review, her team looked at a larger group, more than 200 volunteers exposed through everyday activities. They found concentrations of QACS at roughly double the levels in Hrubec’s results. The Indiana University Bloomington researchers also tested for a wider array of QACs: 19 in all, including a class called alkyltrimethylammonium compounds, or ATMACs.

If verified, the finding would mean Hrubec’s earlier work revealed only part of the story. “ATMACs, based on our data, contribute about 50 percent to the total QAC concentration,” Salamova says. She suspects that, because ATMACs are more easily carried into the air, they are also more readily inhaled and transferred to the blood.

The chemical spraying at Glades and other facilities, as well as the hostile physical and mental treatment that the detainees say is routine, has gotten the attention of lawmakers. Eight members of the U.S. Congress signed a letter on July 22, 2021, that called on the DHS to shut Glades down. But the department has issued no formal plans to do so. Instead, in a report distributed this month to Congress, the DHS inspector general commended Glades and other installations for spraying disinfectants into the air.