LONDON, UK (CBS NEWS) – Decades after the Chernobyl nuclear explosion in Ukraine, the fallout is still evident.

Abandoned dogs roam the disaster zone around the power plant.

CBS News’ Ian Lee was in London with a look at what’s happened to the offspring of pets left behind.

It’s a rescue mission to save the abandoned dogs of Chernobyl.

“A lot of them come up close, they don’t trust you, it’s like they understand what’s going on,” said Manny Maciel, Head of Animal Control.

In 1986, the Chernobyl Nuclear Reactor in Ukraine exploded, sending radioactive material spewing into the sky. Authorities evacuated everyone within 19 miles, but people were forced to leave their pets behind. The Soviet Government sent in the military to kill the dogs, but some survived.

“There were nearly 1,000 stray dogs in the zone when we started this program, and they’re all descendants of these abandoned pets,” said Lucas Hixon, with Clean Futures Fund.

The the past three years, the U.S. non-profit group, Clean Futures Fund, has traveled to Ukraine to track down the dogs and give them medical help.

“I’m not worried about radioactivity. You turn off the lights they’re not going to glow in the dark. These dogs have literally have a piece of grass with high radiation on them,” said Angela Elia, lead veterinary technician.

Vets vaccinate, spay or neuter the animals, and give them a good wash before releasing them back into the wild, while young pups get a new leash on life.

“She loves everyone and doesn’t understand why people don’t wanna stop and pet her all the time,” said Sean Grossarth, an Ohio native, who adopted dog Natalka from Chernobyl last year through the “Dogs of Chernobyl” program.

“It’s by far one of the most rewarding experiences I’ve ever had,” Grossarth.

The transition from Chernobyl to Columbus has been rough at times, but Natalka has setting into her new life with her American family.

Since the adoption program began last year, 40 puppies have been adopted by American and Canadian families. For more information about the “Dogs of Chernobyl Programs, click here.