We Call Nitrous Oxide Laughing Gas, but This Super Pollutant Is No Joke

Industrial N2O emissions come almost totally from the production of two chemical compounds, adipic acid and nitric acid. These two industries account for 100 to 200 million metric tons of carbon dioxide equivalent (CO2e) emissions per year; more than the total greenhouse gas emissions of Belgium. Emissions are also projected to increase, with the U.S. Evironmental Protection Agency (EPA) estimating that almost 400 million metric tons of CO2e will be emitted globally from nitric and adipic acid production in 2050. 

The agricultural sector is the largest contributor to global N2O emissions, accounting for some 3 percent of total global GHG emissions. Tackling agricultural emissions of N2O will be important to ensuring climate stability but will take time: The recent Global Nitrous Oxide Assessment found that reducing agricultural emissions will not reduce global temperatures until the 2090s and will likely require significant societal shifts. 

On the other hand, with industrial N2O cuts, avoided warming can happen quickly and durably. (This is why industrial N2O is often considered the “low-hanging fruit” of N2O sources.) Industrial N2O emissions can be reduced sharply today by using decades-old, commercialized destruction technologies that can be added to existing or newly built chemical manufacturing plants. Technologies include catalytic and thermal destruction processes that irreversibly destroy N2O. These abatement technologies are cost-effective, with more than 90 percent abatement available at reported marginal costs of around $5 per ton of CO2e and even below $1 per ton of CO2e. 

There have been significant prior successes addressing industrial N2O. In the early 1990s, the climate-warming and ozone-depleting effects of N2O, particularly from adipic acid production, were widely publicized. As a result, a voluntary collaboration among six leading adipic acid producers—including DuPont, BASF, and Asahi—led to the development of N2O abatement technology and the subsequent abatement of more than 90 percent of N2O emissions from these companies. The collaboration between competitors was essential to the success of this effort so that no one would gain a competitive advantage by choosing to not abate and thus avoid the associated costs.  

A decade later, the Kyoto Protocol developed a voluntary carbon market called the Clean Development Mechanism, which successfully funded N2O abatement at adipic acid plants in several countries, including two in China. Unfortunately, the credits were too lucrative compared to the actual cost of abatement, resulting in vast distortions of markets and financial waste. Further, once this credit market collapsed, abatement likely ceased at adipic acid facilities in China. Today, Chinese adipic acid dominates both global market share and global industrial N2O emissions. 

Still, there have been other success stories with industrial N2O. In the United States, which is the largest emitter of N2O from nitric acid, half of the country’s nitric acid plants abate their emissions, as do both U.S. adipic acid plants. The European Union’s mandatory Emissions Trading System has funded N2O abatement at all adipic acid and nitric acid plants in the E.U. Globally, the Nitric Acid Climate Action Group, an initiative of the German federal government, has been successful in promoting durable N2O abatement from nitric acid production in 30 countries as a form of development assistance.  

These efforts, however, have largely been voluntary (or incidental; see below). National regulatory standards in all countries with industrial N2O emissions will ultimately be the most surefire way to achieve sustained industrial N2O abatement.  

Currently, China and the United States are the two largest emitters of industrial N2O and do not have N2O-specific regulatory standards. China has indicated that it will begin considering such rules, but we don’t know how quickly that will happen. In the United States, air quality standards for the broader set of nitrogen oxides (NOx), which do not include N2O, have resulted in some incidental abatement of co-emitted industrial N2O. There may be pathways to getting the EPA or states to set specific regulatory standards for N2O in the future.  

The biggest barrier to regulatory standards is the cost that these industries must incur to install and run N2O abatement equipment. N2O abatement from adipic acid production—the world’s largest source of industrial N2O—is cheap in climate terms, at prices below $5 per ton of CO2e. However, so much N2O is produced per ton of adipic acid that even $5 per ton of CO2e would correlate to an additional cost of roughly $400 per ton of adipic acid. In the first quarter of 2026, the price of adipic acid globally was between $1,500 and $1,800 per ton, meaning abatement could increase the cost of adipic acid by more than 20 percent—not insignificant for a low-margin commodity. 

Carbon credit markets have been the main lever to address costs and increase N2O abatement. Voluntary carbon markets have driven recent installations and operation of abatement technologies, such as at an Ascend Performance Materials adipic acid plant in Florida under the 2020 U.S. Adipic Acid Production Protocol published by Climate Action Reserve, a nonprofit carbon registry for the North American carbon market.  

Additionally, in 2023, Climate Action Reserve published a China Adipic Acid Production Protocol, which is currently being applied to three adipic acid N2O abatement projects in China and has the potential to reach dozens more emitters. The protocol sets a production cap to protect against potential market distortions as well as a high floor for credits: Giving credit for 10 percent of the N2O reduction achieved provides enough incentive to make installation and operation of abatement technology attractive; the remaining 90 percent of abatement that’s not credited then goes to climate and ozone protection. High-integrity financing mechanisms such as this one could be effective market movers that help regulations become a reality while safeguarding against generating overly lucrative credits and avoiding perverse incentives. 

Companies looking to invest in fast climate mitigation can seize the N2O opportunity as part of their super pollutant strategies in a few ways. Buyers of nylon, fertilizer, and other relevant materials can play an important role by signaling a preference for N2O-abated products, otherwise known as “buying clean” within their value chains. Those without direct value chain N2O emissions can fund voluntary installation of N2O destruction technology on industrial production plants, potentially mediated by high-integrity voluntary carbon market protocols. These voluntary actions will allow national regulators to eventually step in and make these emissions cuts mandatory through regulatory standards.  

Tackling industrial N2O emissions is a core part of a comprehensive climate strategy, bridging efforts to achieve fast-acting reductions in high-GWP gases like methane and HFCs and reductions in long-lived gases like CO2. Should N2O emissions continue unabated, these emissions (across all N2O emissions sources) could constitute an additional 0.2 degrees Celsius of warming by 2100 and cause stratospheric ozone depletion more severe than during the peak depletion era of 1995–2005.  

Fortunately for us, we have a clear, open lane for fast-acting relief: destruction of industrial N2O with the well-worn technologies of yore. If only every climate problem were so straightforward.