Caffeine Jungle: Child labor, struggling farmers found on 'ethically' certified coffee farms in southern Mexico

It's been a distinction that coffee makers, cafes and other retailers have boldly made over the last couple of years: that the java customers sip every morning was produced under humane conditions and those who cultivate coffee ingredients are fairly compensated.

But a more than year-long investigation by "Impact x Nightline" found evidence of child labor and farmers living in poverty on multiple ethically certified coffee farms in southern Mexico - the heart of coffee production in North America.

While the organizations acknowledged that the scope of the problem makes it difficult for them to fully address, activists say they need to make a stronger effort before more people are hurt.

Impact producers discovered a group of children working on a Rainforest Alliance-certified farm in Chiapas, Mexico in 2021, with some as young as 6-years-old.

One boy told the team he was 12-years-old and had been working the harvest for two months without access to a school.

Mexico's minimum age for working is 15 and Rainforest Alliance policies mandate that children who live on their member farms, must be in school or childcare while their parents work.

At the time of the team's visit in late 2021, the farm's most recent publicly available audit said it was in compliance with most Rainforest Alliance policies, including the prohibition of hiring child labor.

Some adult farmers from other small-scale Rainforest Alliance farms told Impact that they were struggling to provide enough food for their families and it was not unusual for children to work on the farms and help their families, with some estimating that they've seen as many as 20 kids in one community the team visited.

"My 5-year-old nephew, he picks from the small plants," a farmer told Impact.

Watch the full report on free trade coffee on an episode of Impact by Nightline streaming on Hulu.

Fernando Bautista, the Rainforest Alliance's regional lead for Chiapas, initially told Impact that his organization keeps an eye on its farms to ensure that children aren't working, but when presented by Impact reporters with videos and photos of the kids on their farm, he acknowledged that not all of the farms they certify are inspected.

"As an organization, I can tell you that we're working to eradicate all of that [child labor]," he told Impact, adding that the organization would investigate the farms in question.

The Rainforest Alliance would ultimately pull its certification from the three of the farms where Impact saw evidence of child labor during its 2021 trip.

"Child labor is a grave human rights abuse and has no place in a responsible business," the organization said in a statement to Impact.

The organization added that it has adopted an "assess and address” approach to child labor which “goes beyond simple prohibition and helps farmers identify and address the root cause of child labor," because they say "a zero tolerance approach has only driven child labor underground, where it is harder to detect."

“Our system does not promise to be infallible," the Rainforest Alliance said in its statement. “We are trying hard to help prevent, monitor, and remediate situations as we are made aware of them. We are fully aware this often can be an uphill battle."

Amelia Evans, who leads an independent research team that is studying the ethical certification industry and its impact on human rights across the world, told Impact that the ethical certifiers are systematically failing to prevent human rights abuses and it's not possible for them to do full audits of all the farms they certify.

"There is a risk that these initiatives, while they may not mean it, could risk doing more harm than good," Evans told Impact. "They can create a perception that these critical issues are being taken care of, when in fact those issues are being perpetuated."

Evans said the Rainforest Alliance is one of the better actors but said it fails "to systematically address human rights abuses, even though they tend to exhibit good practices."

"The fact is that what we're seeing is certification schemes which are voluntary efforts are simply not enough to address the problem," she said.

Evans added that coffee customers also need to be more cognizant of the issues behind the industry and the efforts to fix them.

"We as consumers need to much more grapple with the complexity of what it means that goods are expensive to produce if we pay people fair wages," she said.

ABC News' Ivan Pereira and Candace Smith contributed to this report.