When farmers stop giving pigs a drug called ractopamine, the leftover traces in the meat disappear quickly—so fast that by the time the pig is slaughtered, there’s hardly any left, and it’s under the safety limits set by regulators.

Pigs were fed a growth-promoting drug called ractopamine for 28 days, and even when they were slaughtered the same day the drug stopped, tests showed no dangerous levels of the drug left in the meat — so regulators say it’s safe to eat right away.

Farmers give pigs a drug called ractopamine to make them leaner, but sometimes they don’t wait long enough before sending them to slaughter—so traces of the drug can end up in the pork we eat.

When pigs eat feed with a drug called ractopamine for a month, the drug builds up way more in their kidneys and liver—organs that clean and process toxins—than in their meat, fat, or blood. This means their body is working hard to get rid of it, so it doesn’t stay in the meat you eat.

When pigs are given a specific drug called ractopamine for a week, the drug shows up way more in their pee than in their meat or blood—so much so that testing their urine is the best way to tell if they’ve recently been given this drug.

When guinea pigs were given a specific drug called ractopamine every day for a week, the drug stayed in their lungs much longer than in other organs—even 30 days later—like it got stuck there and took its time leaving.