Plastic Recycling Via Pyrolysis: Significant Environmental, Health, and Safety Concerns and Limited Economic and Environmental Benefits

   Plastic is notoriously difficult to recycle. There are many different grades of plastic with many different components. Plastic is generally a complex mixture of polymers and chemicals. In the U.S., less than 5% of plastic is recycled. Plastic can only be recycled a few times, unlike aluminum and glass, which can be recycled many times. Recycled plastic often is mixed with virgin plastic, so at best it is really only partially recycled. Mechanical plastic recycling involves washing, shredding, grinding, pelletizing, and other steps. These processes also release VOCs, particulate matter, and microplastic particles into the environment. They are also quite flammable and present very real fire risks at these facilities. Even plant-based “biodegradable," or "compostable” plastics are only partially recyclable. These only make up about 1% of plastics, and only about 1% of that 1% are considered environmentally benign. These bioplastics may also release more microplastics than regular plastic.

     Chemical recycling of plastic is occurring at some facilities, but there are very significant air quality and other environmental concerns with these facilities. One method used is incineration under low oxygen conditions to melt the plastic in a process known as pyrolysis. Other methods of chemical recycling include gasification, solvolysis, and solvent-based purification. According to the Natural Resources Defense Council (NRDC), pyrolysis makes up the bulk of operating and planned plastic chemical recycling facilities, about 80% of them. The NRDC notes that pyrolysis, as well as gasification, are forms of incineration with major toxic impacts. They cite an NREL analysis of pyrolysis that suggests only 0.1 to 6 percent of the plastic waste undergoing pyrolysis can become new plastic. The NREL report also notes that:

“…the economic and environmental metrics of pyrolysis and gasification are currently 10 to 100 times higher than virgin polymers.”

     That certainly suggests that recycling plastic through pyrolysis and gasification is not worth the trouble and will likely cause more harm than good, both environmentally and economically. Pyrolysis is mostly used to turn plastic waste into fuels, highly toxic ones. In 2023, the EPA approved 18 new chemical mixtures derived from plastic waste for use as fuels while also acknowledging that some of these fuels present high risks of cancer. Later, they rescinded some of these approvals, noting the need for further research.

     Pyrolysis facilities also produce large volumes of hazardous waste. The table below from the NRDC report shows the hazardous waste generated from just three facilities. They note:

“If all 26 of the pyrolysis facilities that are currently proposed or under construction are actually built and put into operation, this could mean between 624,000 and 10.8 million additional pounds of hazardous waste generated in, transported through, and disposed of in communities across the country.”

     This hazardous waste is transported to storage and landfills, and transporting hazardous waste has its own risk factors. The map below from NRDC shows where the operating and proposed facilities are, and below the first map is a map showing routes of travel for the hazardous waste from just three facilities. Many of the locations of operating and proposed facilities are near vulnerable communities and are likely to become environmental justice concerns.

     Other methods of chemical recycling of plastic, such as solvent-based and solvolysis methods, do not burn it but dissolve it with toxic chemicals, which also creates significant environmental and health concerns. These also generate significant amounts of hazardous waste. Perhaps it is better to just landfill all plastic. NRDC calls chemical plastic recycling a “false solution,” and it is hard to disagree. Promoting other solutions to the problem, such as making the plastic less toxic to begin with and switching to more benign materials where possible, are better things on which to focus

     Pyrolysis facilities produce toxic air pollution in their local vicinity, but that may vary with the sophistication of the pollution abatement equipment. They have also been associated with noise pollution and unpleasant odors. Conditions such as these tend to reduce local property values.

     Operating plastic pyrolysis facilities have also struggled economically, with some filing for bankruptcy. The difficulty in making a profit also means that they will likely not provide much local tax revenue.

     The bottom line is that chemical plastic recycling is not really viable. ExxonMobil used to promote these methods, but they have proven thus far to be woefully inadequate in solving the problem at best, and toxic to local people and the environment with very little or no benefits at all at worst. Of course, research into chemical plastic recycling should continue. I do not believe that many of these proposed facilities should be built unless they can prove that they can overcome some of these difficult challenges to the flailing industry. Of course, landfills have their own substantial environmental concerns. I also think that of the so-called three R’s: reduce, reuse, recycle, perhaps reduce may have the most utility here. If we can somehow reduce the use of plastic, that would help, but plastic still has many advantages over other materials, including its low weight. The continued proliferation of plastic, microplastic, nanoplastics, and plastic manufacturing and recycling pollution is a problem that is not easy to solve and which threatens to get worse.

 

  

 

References:

 

Planned WV plastics recycling facility could hurt economy, public health. Nadia Ramlagan. Public News Service. October 8, 2025. Planned WV plastics recycling facility could hurt economy, public health

It's time we confront the ugly truth about plastic recycling. Opinion by Holly Kaufman. San Francisco Chronicle. October 8, 2025. It's time we confront the ugly truth about plastic recycling

“Chemical Recycling” Is a Toxic Trap:Chemical recycling is mostly plastic incineration and generates significant hazardous waste and pollution. Renee Sharp. Natural Resources Defense Council. March 11, 2025. “Chemical Recycling” Is a Toxic Trap