Washington, DC–(ENEWSPF)–December 17, 2012) Pets are frequently exposed to toxic chemicals used for lawn care, bug sprays, flea and tick products, and rodenticides. Recently, a dog ingested a zinc phosphide based pellet rodenticide, and threw up these toxic chemicals, creating a toxic gas that caused respiratory stress for four of the veterinary staff where the dog was being treated. The incident happened in Vail Valley Animal Hospital in Edwards, Colorado on December 7, and led to one emergency room veterinarian and three technicians being sent to the hospital. Sadly the dog did not survive after releasing this toxic gas. This is not the first incident of phosphine gas exposure at a veterinary clinic as a total of four have been reported from 2006 to 2011 in Michigan, Iowa, and Washington.
When zinc phosphide is ingested and comes in contact with water it forms a poisonous gas. In a statement, the local fire protection district explained, “When the dog vomited, this released the [phosphine] gas as the pesticide had mixed with the contents in the dog’s stomach.” According to the Centers for Disease Control and Prevention (CDC), inhalation of high concentrations of phosphine gas can be deadly and can cause “damage to the pulmonary, nervous, hepatic, renal and cardiovascular systems.” The Vail Valley staff suffered from respiratory distress, including tightening of the chest, burning of the throat, and difficulty breathing.
Zinc phosphide, which can be found in products such a as Mole Tox (Bondie) and Dexol Gopher Killer (Value Garden Supplies), is commonly used in rodenticide products. Zinc phosphide is an anticoagulant type poison that kills by blocking vitamin K-dependent synthesis of the blood clotting substance prothrombim, which causes rodents to bleed to death. Compared to other chemicals used in anticoagulant rodenticides, it takes a minute amount of zinc phosphide to poison pets. For example, it takes 160 ounces of chlrophaclnone, another rodenticide, to kill a 10 pound dog where as it only takes .16 ounces of zinc phosphide to kill a dog of the same size. Pets can not only be exposed to zinc phosphide through contact with poison bait stations, but also by eating rodents that have been contaminated with these poisons. Pets often eat rodents that died from eating poison from bait stations, and these rodents pass on the toxicant to pets. Some rodents have developedresistance to certain rodenticides, meaning that they are able to carry around high levels of the toxic chemical in their body, which can poison pets that hunt down these rodents.
The Environmental Protection Agency (EPA) has been working to phase out some of the most dangerous rodenticide products. In 2007, EPA proposed a requirement that all over-the counter rodenticides sold for residential use should be available only in tamper-resistant bait stations to reduce incidents of accidental exposure. In 2008, EPA issued its risk mitigation decision requiring manufacturers to adhere to four primary requirements. These requirements included a ban on the sale of pellet formulations, which was the formulation involved in the Colorado dog poisoning. Since 2008, three manufacturers still market products that are not in compliance with EPA standards: Reckkit Benckiser LLC, Spectrum Group Division of United Industries Corporation, and Liphatech Inc. Despite strong industry pressure, EPA has made it known that it intends to release a final cancellation order for these products by 2013, which would restrict household use of these products.
Rodenticides are not the only pesticide that can poison our pets. This past August in Utah a golden retriever named “Rusty” died after inhaling the toxic herbicide TruPower3 prior to the chemical being applied to a neighbor’s lawn. The dog’s owner, Ms. Pammi, provided Beyond Pesticides with this statement from Rusty’s vet:
“The herbicide Trupower, which contains a mixture of 2,4-D, mecoprop-p,and dicamba and a class of phenoxy chemicals, has the potential to cause mild to severe signs in dogs depending [on] amount and concentration of the compound ingested.”
For more information on the effects of pesticides on pets, please read Beyond Pesticide’s “Pesticides and Pets” fact sheet.
To avoid these tragic pet poisoning incidents, Beyond Pesticides advocates for using Integrated Pest Management (IPM) strategies for rodent pest control. IPM is a program of prevention, monitoring, and control that offers the opportunity to eliminate or drastically reduce the use of pesticides and minimize the toxicity of and exposure to any products that are used. For more information on least-toxic control of rodents, please read Beyond Pesticide’s “Least Toxic Control of Mice” fact sheet. By using these least toxic strategies you will not only protect your pets from possible contamination but also wildlife that often will feed on rodents that have ingested rodenticide poison.
For more information on least-toxic alternatives to pest problems, please visit Beyond Pesticides alternatives page.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.