Police K9s overcome training smoke toxicity

With September marking National Service Dog Month, Pet Poison Helpline recently highlighted a case of 2 police K9s who fell ill during a training exercise after being exposed to high concentrations of hexachloroethane smoke.¹ In the US, the military uses the hexachloroethane for military or law enforcement tools designed to create heavy smoke clouds.^2,3

Django. (Image courtesy of Pet Poison Helpline)

The K9 dogs, Xander and Django, developed lethargy, vomiting, and respiratory sign shortly after they were exposed to the hexachloroethane smoke.¹ Jordan Cross, K-9 deputy at the Missoula County Sheriff's Office in Montana—the same department where Xander and Django serve as police canines—said Django became immediately lethargic and vomited shortly after. Django and Xander then rested for 15 minutes, but Django vomited again and coughed up mucus. According to Pet Poison Helpline, the dogs were monitored overnight, but when they continued to exhibit respiratory symptoms, they were brought to Ancare Veterinary Clinic in Missoula. The team at Ancare then contacted Pet Poison Helpline.

"It was a very good lesson," Deputy Cross said in a Pet Poison Helpline news release.¹ "We were doing a joint training session with the SWAT team when 2 of our department's canines, Xander and Django, had a chemical exposure. We use two types of material. One is...2-chlorobenzylidene malonitrile tear gas, and the other is...hexachloroethane smoke. The dogs did well with the gas, but we made an error with the smoke. It is supposed to be used in an open environment, but we used a higher concentration in an area that had a shed, and smoke accumulated in the building. When the canines went into the environment, there was too much smoke concentrated in a confined area. Basically, our poor planning negatively affected their airways."

Previous studies have found that hexachloroethane is “moderately irritating” in humans’ skin, mucous membranes, and liver. Animals exposed to hexachloroethane have exhibited neurological, liver, and kidney effects.^2,3 Older Environmental Protection Agency documents classify hexachloroethane as a Group C, possible human carcinogen.²

Once the dogs were at the Ancare, the veterinary team there and Pet Poison Helpline devised a treatment plan that consisted of oxygen therapy, pain medication, chest x-rays, and several gastrointestinal protectants. According to Pet Poison Helpline, the team was also worried about the patients’ liver function. However, both dogs have experienced a successful, complete recovery and are back at work.

"Law enforcement officers are used to dealing with emergency situations, and fortunately so are we," Renee Schmid, DVM, DABT, DABVT, a senior veterinary toxicologist and director of veterinary medicine at Pet Poison Helpline, said in a news release.¹ "The dogs had a strong reaction to the [hexachloroethane] smoke, which creates zinc chloride when it is discharged. Since September is National Service Dog Month, and police officers are also lifesavers, we thought it was a perfect time to share their story."

"This was the first time Xander and Django experienced live gas and smoke," said Deputy Cross.¹ "The point was to get them used to it, so they'd be ready when the real thing happens. We'll know what to correct in the future, and that's the point of training. We all learned from this mistake."

References

1. Police dogs leap into toxic training situation. News release. Pet Poison Helpline. September 10, 2025. Accessed September 10, 2025. https://prnmedia.prnewswire.com/news-releases/police-dogs-leap-into-toxic-training-situation-302550259.html
2. Hexachloroethane. Environmental Protection Agency. January 2000. Accessed September 10, 2025. https://www.epa.gov/sites/default/files/2016-09/documents/hexachloroethane.pdf
3. National Center for Biotechnology Information. PubChem Compound Summary for CID 6214, Hexachloroethane. https://pubchem.ncbi.nlm.nih.gov/compound/Hexachloroethane. Accessed September 10, 2025.