Rats give us plenty of grief. They can cause outbreaks of diseases ranging from scrub typhus to leptospirosis and their urine and feces are thought to render a fifth of the world's food supply unusable. As Chris Sweeney writes in a lengthy piece for Audubon Magazine, second-generation anticoagulants are effective rat killers, and we're using them more and more: sales of those products hit $3.8 billion last year, and are set to reach $5.8 billion by 2027. The US is behind a third of those sales—but US consumers shouldn't be, which brings us to the crux of Sweeney's piece. Under EPA rules from 2008, rat poisons containing these second-generation rodenticides (brodifacoum, bromadiolone, difenacoum, and difethialone) may not be sold in "channels of trade" that could end with retail sales in places ranging from hardware stores to big-box stores. Ecommerce isn't listed there.
And so Sweeney had zero problem scooping up buckets containing the stuff via online shopping: from Amazon, eBay, Walmart.com, diypestcontrol.com, and more, and that online shopping soon triggered the appearance of ads for the stuff. What's the danger? To the environment, a potential big one, due to the chemicals' long half-life. Should a hawk or owl eat a rat that has ingested second-generation anticoagulants, "the chemicals can stay lodged in animal tissue for months—posing an ecological menace." Sweeney tried mightily to talk to the online retailers, third-party vendors, and manufacturers tied to the consumer sales, and got almost nothing out of them. The head of Massachusetts-based Yankee Pest Control was more forthcoming, saying that best pest-control experts use the chemicals as a last resort (it turns out pumping rat dens with carbon monoxide works, too). He agrees they shouldn't end up in consumer hands. "There’s a reason we don’t sell hand grenades to people," he quips. (Read the full story, which looks at the measures the EPA has taken over the years related to their use.)