Nearly every state-led effort to ban food waste analyzed by researchers appears to be failing - except one, according to a new study.
The study, published Thursday in the journal Science, singled out Massachusetts for reducing the amount of food that gets tossed in the trash. But its more troubling findings in other states reveal how one of the most seemingly straightforward ways to tackle climate change is, in practice, a tough problem to solve.
Food waste is a pressing national problem. Of the millions of tons of food in the United States, more than 30% goes unsold and uneaten, according to ReFed, a research and advocacy group that works on food waste. Spoiled food makes up the single largest volume of material sent to landfills and incinerators, where it decomposes, releasing methane - a powerful greenhouse gas that is heating the planet. A study by the Environmental Protection Agency found emissions from food waste in the United States are roughly equal to more than 50 million cars on the road.
Nine states have passed food waste bans aimed at businesses such as chain restaurants and supermarkets. Researchers studied the first five laws and found that from 2014 to 2018, Massachusetts reduced its solid waste by an average of 7.3%. But similar legislation in the other states - California, Connecticut, Rhode Island and Vermont - had no discernible effect. States with newer laws were not included in the study because they did not have sufficient data.
“What was surprising to us is, despite the political support for these bans, and their importance, they seem to not be working as policymakers would have expected - and as they would have hoped,” said Fiorentia Zoi Anglou, a PhD candidate at the McCombs School of Business at the University of Texas at Austin, who co-authored the study.
The study identified several factors that could explain Massachusetts’ success.
First, the state had built the most extensive network of food-waste-composting sites, making it relatively simple and affordable for businesses to divert food from landfills and incinerators. Massachusetts’ law had no special exemptions and was easy for business owners to understand. Massachusetts also increased the cost of not following the rules and had conducted the most compliance checks.
“By contrast, there is almost no enforcement in other states,” the study’s authors wrote. The effect of other four bans, or lack of effect, “suggests widespread noncompliance with US food waste bans - i.e., that food waste is still being landfilled despite the bans,” they wrote.
The Massachusetts example shows states’ food waste bans hold potential, Anglou said. But, she added, “in order for them to be truly effective, they need more than good intentions. They need to support the laws with sufficient composting infrastructure and enforcement.”
By changing businesses’ behavior, researchers found, Massachusetts also significantly lowered its methane emissions, which fell about 25% per ton of disposed waste in the post-ban years.
Massachusetts Gov. Maura Healey (D) praised the state’s results in a statement.
“In Massachusetts we pride ourselves on being leaders,” Healey said. “Kudos to the team at MassDEP for the hard work they’ve put in to make this initiative so successful and a special credit to our state’s businesses and institutions that have stepped up to the plate to innovate and reduce their waste,” she said, referring to the state Department of Environmental Protection.
The researchers compared the five early-adopter states to similar states that did not pass food waste bans. This allowed them to estimate of how much food each state would have sent to landfills had they not enacted bans. The study compared those results to actual outcomes, using states’ own reports of their municipal solid waste disposal.
Anglou described the findings as revealing but said more research is needed to understand which factors are responsible for the Massachusetts success. The study also did not analyze the laws’ results after 2018 because of pandemic-related data complications, which left out states’ more recent efforts. Two years ago, California began formally requiring jurisdictions to enforce the state’s food waste ban, a change that could improve its effectiveness in the long-term, she said, but which was also outside the scope of this study.
Dana Gunders, head of ReFed, said the study confirmed Massachusetts’ approach.
“There are laws on the books in Connecticut and Rhode Island, but I’m not sure how much attention is going to this overall,” Gunder said. Both states exempt businesses from having to keep food out of the trash if there’s no composting facility nearby, she said, which may have made their bans less effective.
Terry Gray, director of Rhode Island’s Department of Environmental Management, acknowledged the state’s ban has not worked as intended. The law’s passage was supposed to encourage developers to build new composting facilities, he said, but “for a number of reasons those investments have not happened yet, and the infrastructure has not been developed.” Gray said Rhode Island and other states got new funding from the Environmental Protection Agency this year to tackle the problem.
Massachusetts has dedicated staff and funding to carry out the law, Gunder said, and conducted vigorous outreach. The average restaurant owner doesn’t always pay attention to new laws, she said, adding: “Very extensive outreach needs to happen to get businesses to participate, and I think in the early days Massachusetts did a lot of that.”
Massachusetts still fell short of its 2020 goal to keep food out of landfills, advocates noted. State officials have since set an even more ambitious goal for 2030.
Gunders said she was surprised to see Vermont’s food waste ban, which covers both businesses and homeowners, listed as ineffective. Josh Kelly, the solid waste program manager for Vermont’s Department of Environmental Conservation, also took issue with the study’s conclusion.
Although food scraps still make up a large portion of the state’s waste stream, Kelly said, the tonnage has decreased by 13% since 2018. “We need to do more,” he said. Kelly noted that Vermont has collected data on how much food waste is now being composted, used for animal feed or “digested” by microorganisms, and “their tonnages have risen.”
Solid waste officials in California and Connecticut said they also believe they are getting results. California diverted 11.2 million tons of organic waste from landfills in 2022, the most recent data available, according to the state’s recycling agency. A Connecticut spokesman said the state has seen the tonnage of organics waste diverted triple in volume in recent years.