Decades of unfettered pollution from dry cleaners have caused a quiet disaster in California

Published on
February 6, 2024

Dry cleaners are just about everywhere. 

You’ll spot them on the corner of your block, in the neighborhood strip mall, in malls and across the street from schools and hospitals. They’re unassuming, usually housed in small buildings with minimal signage. They’re easily overlooked by a typical passerby. 

It’s what’s underneath that’s cause for concern. 

Dry cleaners in California used, up until this year, a toxic chemical called perchloroethylene, or PCE for short, to launder clothes. The chemical is particularly effective at ridding clothes of tough stains. 

But misuse, accidental spills, and leaks from pipes and underground storage tanks meant the chemical found its way into the soil beneath dry cleaners. From there, it flowed deeper until it hit groundwater, eventually settling to the bottom.

PCE likely began polluting the soil and groundwater beneath dry cleaners in the 1940s and went undetected until the late 1980s. California banned the substance from use in dry cleaners as of Jan. 1, 2023. People exposed to PCE are more likely to get kidney cancer, bladder cancer and kidney disease, according to the U.S. Agency for Toxic Substances and Disease Registry. 

I first learned about PCE and its impacts while reporting about a grant the city of San Luis Obispo had earned so it could clean up its groundwater. The city on California’s Central Coast had discovered that just a few dry cleaners in town, most closed down by now, had created a large plume of toxic PCE polluting the groundwater. 

A fellow reporter, Adam Echelman, who was at The Modesto Bee at the time, said there was a lot more to the story than just San Luis Obispo’s polluted water. He had recently finished a series of stories about how the city of Modesto won a lawsuit against chemical companies for knowingly selling PCE to dry cleaners in the area. 

He encouraged me to look into how widespread this issue was of PCE pollution from dry cleaners. 

What I found was surprising. 

Studies estimate that at least 75% of dry cleaners have caused plumes of PCE contamination under their businesses. These plumes can stretch for miles, flowing under homes, businesses and hospitals. 

PCE can volatilize, or transform from a liquid into a gas, and then seep upwards through cracks in foundations and sidewalks, where it can then be breathed in. The chemical also doesn’t break down easily, so many former dry cleaners turned into restaurants, cafes or salons could have fumes from a forgotten plume leaching into their air. 


As I dove into the story as a 2023 California Health Equity Fellow, it quickly became clear that the problem of PCE pollution touched nearly every city and every town in California. 

I began interviewing experts familiar with the science of PCE contamination and how it could leach from a concrete floor down into the soil, then the groundwater and perhaps back up in the form of toxic fumes. I asked them how widespread this contamination was and got back a lot of shrugs and exasperated sighs at the sheer complexity of the problem. 

I spoke to environmental consultants who had worked on dozens or even hundreds of PCE cleanup projects. Each one explained how expensive it was to rid the soil and groundwater of the chemical — often drumming up bills for the dry cleaners in the tens of millions of dollars. 

The state officials I spoke to said they knew about the problem — it was just too big of a problem. They weren’t equipped to handle it, they said, there wasn’t enough money or time. 

I found out that if the state agency largely in charge of dealing with the pollution maintains its current annual funding for the dry cleaner cleanups, it could take from 220 to 2,941 years to fund the necessary remediation. 

Meanwhile, countless communities across California sit atop dry cleaner pollution plumes, many unknowing of the invisible threat. 

As I interviewed dry cleaner business owners, another story began to develop. They told me about how they’d felt betrayed by the state, which had, for so many years, allowed them to use PCE with few guidelines except to control fumes once emitted from dry cleaner machines, and now they were being punished. 

They said generations of dry cleaners before them didn’t know that it was wrong to pour used PCE down the drain. Or an accidental spill on concrete floors didn’t seem like that big of a deal. 

Now, many face cleanup bills of $1 million to more than $10 million if the state finds a plume of PCE pollution originated from their dry cleaning business. The bills are far too much for many to cough up for the dying industry, as state grants can be tough to find and don’t cover the brunt of the costs. 

During my reporting, I looked to other states for solutions. Many had created PCE plume remediation funds by taxing the sale of the chemical and requiring dry cleaning businesses pay annual fees to avoid financial liability should a plume of contamination be found beneath their business. 

But the states where PCE pollution had been mostly handled were often much smaller than California. The states had needed to deal with pollution from just a few hundred dry cleaners. 

In California, there are at least 7,500 dry cleaner sites where pollution could be present. 

A big challenge through reporting on my series of stories about PCE pollution was that I also had to maintain my daily beat reporting. I have two beats at The San Luis Obispo Tribune: education and environment issues. 

I found myself taking time outside of my normal work hours to report on the PCE project. At times, it became unmanageable and I quickly found myself beginning to burn out. It was hard, however, to justify taking time off from either: my beat reporting was necessary for The Tribune to fill papers and meet pageview goals, while the USC Center for Health Journalism had granted me money to dutifully pursue the PCE project. 

Eventually, I found a balance between foregoing some of my beat stories, which in some cases could be passed along to other reporters in the newsroom, and dedicating more time to the PCE project. I was then able to travel to Lake Tahoe, Sacramento and Los Angeles to pursue deep dives into the dry cleaner pollution issues there and interview dozens of sources. 

Although I ended up reporting enough to fill a three-part series, there is certainly a lot left to uncover. 

The state has changed the goalposts on PCE pollution, making it more difficult to meet strict health standards that many environmental consultants say are unnecessary. Plus, PCE pollution may not be limited to the soil and groundwater: It could be leaching into rivers, streams and the ocean. 

I received incredible feedback from my series, mostly from folks in the dry cleaning or environmental consulting industries who were thankful I’d shed light on this issue. 

I hope my series can inspire journalists in communities across California and the rest of the nation to look into the groundwater issues near them and ask whether PCE is present.