Study reveals alarming lead and mercury levels in popular dog foods

A new study found that popular dog foods on the market contain "alarming" levels of lead, mercury and other contaminants.

The findings come from Colorado-based nonprofit Clean Label Project, which tests and certifies consumer products.

The study into the multi-billion dollar dog food industry found what the group says is high levels of contaminants like arsenic, cadmium, mercury and lead in your pet's dry food.

According to the study, dry food has the highest level of contaminants. A close second is air and freeze-dried dog food.

The best option for your pet? Fresh or frozen, human-grade food that you could eat yourself.

The report looked at 79 of the top-selling dog foods but didn't call out specific brands.

"I don't think anyone, any group, any company, sets out to contaminate food," said Molly Hamilton, the CEO of Clean Label Project. "I think they love their dogs as much as I love my dog ... I think it just needs to have more attention brought to it."

The study found ingredients like meat byproducts, added vitamin and mineral premix and seafood and plant-based carbs were likely contributors.

Traces of these contaminants have been found in our food supply for decades. The 1950s saw a major rise in the industrialization of our food with a boom in factory farming and the invention of quick, cheap meals, like television dinners.

It has led to the consumption of more ultra-processed food -- for humans and for our dogs.

"We try and be prescriptive and not cause total panic, but say, hey, here are the options," Hamilton said.

The best fresh and frozen dog food can run you hundreds of dollars a month, so is it worth it? The answer is complicated.

"As much as we wish we could deliver it all on a silver platter that it's got the most nutritious ingredients with the lowest contaminants at the best price point, we just look at the data and we say, here's what we tested," Hamilton said. "This is what we found to bring attention to it. Ideally it would all align. That's not necessarily the case."

There is concern that eating these contaminants could do real harm.

"These dogs are having the same food almost every day for their entire lives," Hamilton said. "We need more studies to say, okay, the dogs that are getting sick, is diet playing a role?"

NBC News reached out to the FDA for comment and has yet to hear back.

Hamilton said an educated and empowered consumer is a pet's best friend until federal regulations catch up.

"You know, that's the beauty of independent consumer testing, is that you can say, I don't need the government to tell me how to get something better," Hamilton said.