The laws regarding rodenticides have changed, and people should be aware that new poison product lines could pose an increased risk to children and pets.
The Environmental Protection Agency and Reckitt Benckiser, the maker of d-CON rat and mouse poisons, agreed in May to start cancelling 12 d-CON products that no longer meet EPA safety standards. Reckitt began to phase out production of the products in June, and production will completely stop by Dec. 31.
By March 31 of next year, distribution to retailers will end, and once those last supplies are sold, the cancelled products will no longer be available to consumers.
According to the EPA, the cancelled products are dangerous because they are sold without bait stations, which help protect children and pets from accidental contact with the poisons. Also, eight of the 12 products contain anticoagulants that pose a significant risk to predatory wildlife that feeds on rodents.
In addition, “mouse and rat poison products meeting our safety criteria are now widely available, effective and affordable, and pose significantly less risk to people, pets and wildlife such as mountain lions, eagles and foxes,” the EPA states on its website.
However, Dr. William Rose, a long-time veterinarian in Perham, believes some products that are replacing the cancelled poisons could actually pose a bigger threat to pets, children and any wildlife that happen to come in contact with them.
For, while there’ll be a much shorter time window in which predatory wildlife could accidentally eat a poisoned rodent, the poisons that are now preferred have much more drastic and fast-acting effects.
With the older products, Rose explained, it typically takes 5-7 days for a rodent to die from the poison. This increases the likelihood of accidentally sickening other wildlife, as that leaves 5-7 days for the rodents to continue to roam around outdoors, where predators like eagles or foxes will nab them for food, thus ingesting the poison themselves and often dying as a result.
Rose has witnessed the problem himself: last fall, an eagle that had eaten a poisoned rat was brought to his vet clinic. The eagle didn’t survive the 15-minute trip from New York Mills to Perham. Rose said rodenticides destroy an animal’s liver, kidneys or nervous system, depending on the product.
Still, he said, the situation could be worse for household pets and children who are accidentally poisoned in the future.
When the EPA banned the use of certain anticoagulant rodenticides for household use, manufacturers were left with the choice of using more toxic anticoagulants such as bromethalin or cholecalciferol. According to information in the September/October 2014 edition of “Today’s Veterinary Practice,” the makers of d-CON feared the new rules would lead to increased bromethalin use, “increasing the risk of poisoning in pets and children due to its potency as a neurotoxin and the lack of an antidote.”
In May, d-CON announced that it would try to avoid bromethalin use by using diphacinone instead, which has a longer duration of action and thus would leave more time for treatment in case of accidental ingestion. There is also an antidote for diphacinone, while there is not one for bromethalin.
All the new poison products approved for sale will require the use of bait stations, which contain the poisons and help keep pets and children away from them, but Rose said they’re not fool-proof. Rodents will sometimes dig pellets out of the traps, he said, and leave them laying around for kids and pets to get into.
If this happens with newer products containing more toxic poisons like bromethalin, it’s very bad news for the animal or child who’s exposed. Rose said the higher toxicity and fast-acting nature of the newer products leave very little time for treatment, and treatment is complex and expensive. He said these poisons kill, almost exclusively, in less than 12 hours.
“I save almost 100 percent of the d-CON poisonings that come in now,” Rose said. “With that, you have maybe 3-4 days before you notice an illness, and...with the right treatment, he (the pet) can still be saved. And it’s so simple to treat.”
But if a pet consumes the more toxic poisons, Rose explained, it’s usually too late for treatment by the time symptoms start to show. In one case he’s seen, a dog started having seizures just one hour after ingesting a highly toxic poison. At that point, he said, treatment would have cost an estimated $15,000 and the chance of survival was only about 10 percent. With older products, the dog would have had more time to show symptoms, and treatment would have been simpler, much less expensive and much more effective.
Rose, who is not a medical doctor, also speculated that the situation would be just as dire for small children.
“A two-year-old who eats a teaspoon-full of this stuff could be killed or will end up in the hospital for two weeks to a month,” he said.
Signs of poisoning vary depending on the product, but can include muscle tremors, abdominal cramps, impaired movement, loss of appetite and seizures.
Rose said he doesn’t want to scare people with this information, he just wants them to be aware of the product changes and know what they’re buying.
“People are used to the old d-CON types of rat poison, which aren’t as urgent,” he said. “But this is different.”
“Make sure you know what you’re putting out, keep the packaging (in case you do suspect a poisoning, you should bring the packaging with you to the veterinarian or hospital so the appropriate care can be given), and be especially cautious in the spring, because that’s when poisons get dragged out most,” Rose said. “I just hate to see pets come in, sick with this stuff.”
Rose recommends using old-fashioned snap traps to kill mice or rats. He admits these are “less pleasant” to work with than poisons because you have to physically deal with the dead rodent in the trap, “but it’s still the safest thing out there.”
Those who do choose to use rodenticides should read the labels carefully and follow all instructions for use. Look for diphacinone, which has an antidote and is a bit slower-acting, and avoid bromethalin, which is faster-acting and has no antidote.