In an attempt to curb the killing of thousands of wild bird and animal species that fall victim to rodenticides every year, scientists and wildlife advocates are trying to raise awareness of the dangers of using second-generation anticoagulant rodenticides for pest control. Popular rat poisons such as Hot Shot, Generation and d-Con are used extensively by farmers and exterminators to kill rats and mice, but often end up in our food, poison our water and sicken our children. Rat poison is, after all indications, not a suitable pest control method anymore.

And recent reports offer plenty of reasons why we should stop using it completely. First of all, the second generation of pesticides has been developed in response to the tolerance rats appeared to have developed to warfarin, the poison contained in the first generation of rodenticides. Unlike the previous versions, second- generation poisons do not kill the rat as fast as the first type, and in many cases rodents “continue to eat long after they have ingested a lethal dose. By the time they expire, or are about to, they contain many times the lethal dose and are therefore deadly to predators, scavengers, and pets.”

A Real Danger to Pets and Wildlife

Before they die, poisoned rats may tempt foxes, coyotes, wolves, skunks, raccoons, dogs and even housecats to consume them, causing lethal and sublethal poisoning from ingesting such large quantities of rodenticide. According to the National Pesticide Information Center, direct exposure to second-generation anticoagulant rodenticides may lead to internal bleeding in any part of the body, also causing difficulty in breathing, weakness and fatigue. Less typical symptoms in animals that have ingested toxic substances include vomiting, seizures, shaking, bloody stools and abdominal pain.

Indirect exposure (relay toxicosis) can cause just as much damage as direct ingestion of rodenticides. Chemicals build up in the skin, lungs and intestine of animals and birds (especially in the organs of younger animals or those under stress from migration),and if a sufficient quantity is ingested in a given period of time, the predator can suffer from even greater harm than the prey. A known example is what happened to bald eagles and peregrine falcons, which ended up on the brink of extinction after consuming fish contaminated with insecticides.

Humans Are Affected, Too

According to an extensive survey conducted by the Environmental Protection Agency over a period of four years, poisoning symptoms have been identified in more than 25,000 children under age six between 1999 and 2003. Annually, parents make over 16,000 calls to the Centers for Disease Control and Prevention to report that their children have ingested rodenticides, either directly off the ground or from around the house and property.

The proven serious threats posed by rat poison to human health and the environment will hopefully lead to the banning of such dangerous substances and to the changing of ineffective policies. With the help of professional pest control companies, who are putting a lot of effort into the development of safer and innovative rat control methods, we can attempt to mitigate the significant impact pesticides and rodenticides have on the environment and the harm caused to wildlife. Perhaps we may never be able to abandon these methods completely and stop producing environmental and natural disasters of such high proportions, but we can at least try to use them wiser and with greater care.

About the Author

Daniel Mackie, co-owner of Greenleaf Pest Control, is a Toronto pest control expert well-known as an industry go-to guy, an innovator of safe, effective pest control solutions, and is a regular guest on HGTV. Mackie, along with business partner Sandy Costa, were the first pest control professionals in Canada to use detection dogs and thermal remediation for the successful eradication of bed bugs. In his free time, he is an avid gardener.