Officials call for limits on use of super-toxic rat poison


D-CON kills rats and mice, the label reads. And, according to state and federal officials, it can kill hawks, owls, eagles, foxes, bobcats, mountain lions and other non-targeted wildlife too.

So can competing brands. Pesticide manufacturers have been selling a new generation of more potent anticoagulants because mice and rats have built up some resistance to the old standby warfarin.

These super-toxic rat poisons have a longer half-life before they break down, meaning they are more effective at working their way up the food chain -- not only killing rodents but their natural predators.


The California Department of Fish and Game has confirmed 240 cases of non-targeted wildlife being exposed to the anticoagulants that work by causing animals to bleed to death.

The list is long. It includes the San Joaquin kit fox, as well as the coyote, red fox, gray fox, black bear, badger, fox squirrel, mountain lion, bobcat, golden eagle, great horned owl, barn owl and turkey vulture, according to a letter issued last year by the Fish and Game director.

It noted that 79% of San Joaquin kit foxes, protected as endangered of extinction, have been exposed to these powerful anticoagulants, as have 92% of raptors in San Diego County.

It cited the statistics to urge the California Department of Pesticide Regulation to restrict the sale of the rodenticides mostly to professional pest-control operators, rather than making them available to urban and suburban homeowners.

The U.S. Environmental Protection Agency has also been pushing to ban the sale of 20 such rodenticides to average consumers and to require loose bait and pellets to be secured in bait stations that are inaccessible to children and pets.

The EPA’s concern: The American Assn. of Poison Control Centers receives 12,000 to 15,000 reports a year of children under the age of 6 being exposed to these poisons.


Manufacturers are pushing back, with lawyers and lobbyists.

Reckitt Benckiser, the maker of d-CON, argues that the EPA has overstated the potential risk of the second-generation pesticides. It states that the EPA standards, which first approved this new generation of rodenticides, shows “its existing products provide far greater benefits than risks to users, to children and wildlife.”

That doesn’t sit well with wildlife rehabilitation workers at Wildcare, which runs a wild-animal hospital in San Rafael. It has found that 74% of the predators that come through its doors test positive for rat poison.

“These are animals that we rely on to do our natural rodent control, and we are poisoning them,” said Kelle Kacmarcik, a Wildcare manager. “That’s shocking in a place like liberal, well-educated Marin County.”

Meanwhile, other public health and conservation groups have joined the fight this week.

The Center for Biological Diversity, the American Bird Conservancy, California for Pesticide Reform and Earthjustice are now pushing for a ban on the super-toxic poisons.

“You don’t have to use the worst of the worst, that not only endanger wildlife but human health,” said Jonathan Evans, an attorney with the Center for Biological Diversity.

Evans said he was sympathetic to those who wanted to rid their homes of rats and mice. Old-fashioned snap-traps work well in rodent control, he said, as does sealing up buildings to make them rodent-proof, removing sources of food and nesting material. And then, there’s relying on natural predators, such as owls, coyotes, bobcats and foxes.