The label on the grocery package contains the reassuring words, “sustainably sourced.” But what does that actually mean for the environment?

Researchers at the University of Minnesota are trying to answer that question with a careful study of one of the world’s largest commodities — sugar. They examined a project called Bonsucro, which promotes a set of voluntary water-use and farming standards for sugar cane and has been adopted by some of the world’s biggest sugar buyers, including General Mills and Coca-Cola.

The findings, published last month, show that if sugar cane growers and major buyers across the globe meet Bonsucro standards, the environmental benefits would be great: Greenhouse gas emissions from sugar production would be halved and water use would be cut by two-thirds.

It’s a groundbreaking and rigorous vindication of the ever-expanding “sustainability” certifications that companies are vowing to meet.

But it comes with a big catch.

The problem is that attaining the full benefits of Bonsucro would require what may be practical and political impossibilities, such as closing off a third of India — the world’s second-largest sugar producer — to sugar farming because it doesn’t get enough rainfall.

As a result, companies might not be able to achieve 100 percent compliance by a certain date unless the standards are relaxed, exceptions are created for regions like India, or a third of that nation’s sugar farmers receive enough incentives to replace sugar with a new crop, said Derric Pennington, one of the study’s authors and adjunct professor at the University of Minnesota.

“These are wicked problems,” Pennington said. “It’s not an individual company issue, it’s an industry issue.”

For General Mills, the study shows both the potential and the hard realities of Bonsucro certification, said Kevin O’Donnell, the company’s director of sustainability sourcing and operations.

The Twin Cities food and cereal giant has committed to having 100 percent of its sugar cane come from Bonsucro-certified producers within the next few years.

While the potential benefits are heartening, he said, it is very difficult to shift the production of sugar cane to different areas of the world. You can’t tell India, “Sorry, you can’t grow sugar cane anymore,” O’Donnell said.

“That doesn’t mean you can’t make progress,” he said. “It’s just harder to do.”

The company met its 2018 goal to have 70 percent of its sugar cane certified and is still on track to get to 100 percent, O’Donnell said.

Minnesota logging

Bonsucro was created by a large coalition of environmental advocates and major growers and buyers such as PepsiCo and Coca-Cola. It’s promoted by the World Wildlife Fund and based in London.

It sets dozens of criteria for sugar production, including labor standards as well as pesticide use, carbon reduction and bans on using land classified with “high conservation value.”

Certifications like Bonsucro exist for just about everything that grows, from palm oil and cotton to salmon. The state of Minnesota boasts that more than 90 percent of the forests under its management have been certified as “sustainable” for logging, allowing for the lumber to be sold with that label, often at a premium.

Yet there’s been little research into the actual global environmental benefit that results from the approved practices, or what would happen if more major players adopt them, Pennington said.

Pennington and the U hope the study can serve as a framework allowing governments, corporations and shoppers to judge the merits of such certifications. The Bonsucro study is designed to be replicated for other commodities and certification standards, he said.

‘Locations matter’

Too often, companies and governments using sustainability standards measure success by the percentage of farmers or produce that gets certified under a standard, Pennington said, rather than by the actual reduction in, for example, greenhouse gas emissions.

That’s a problem because, as the case of sugar shows, the location of the growers matters much more to the environment than the number who achieve certification.

The study found that greenhouse gas emissions would be cut by 51 percent if every sugar grower in the world became Bonsucro-certified, even if they produced twice the amount of sugar as they do today. Water usage, a huge problem at Pepsi and Coca-Cola plants in India, would be cut by 65 percent, while the amount of pollution caused by fertilizer runoff would be reduced by 34 percent.

But half of those benefits come from just 10 percent of the land where sugar is currently grown, the study found. Put another way: If 90 percent of the world’s growers adopted the sustainable practices, it would have the same effect as if 10 percent did in the most sensitive areas of the globe.

“Locations matter,” Pennington said. “The regions that produce the biggest impact are the furthest from compliance.”

The study does not detail the added costs of meeting certification goals, which would be much different for farms in rain-heavy Brazil than in drought-prone parts of India and Pakistan. Those costs have to be borne by someone, and who bears the cost could play a major role in how effective these certifications become, said Stephen Polasky, an economist at the U.

“It almost has to be viewed as a cost of doing business — where enough of the big players buy in to establish a new norm,” Polasky said.

Bonsucro’s leaders are using the study to revise some of their standards. Pennington would like to see more research to show how some of the regions furthest from compliance can get there and whether that’s best accomplished by government incentives, stricter regulations or consumer demand.

“We have to start asking these questions,” Pennington said. “Should we have floating standards for different parts of the world? Should we water down some of the standards to try to at least get farmers to be better? Or is that just kicking the can down the road because it still wouldn’t be sustainable?”