In September, Texas Tech University’s Whitacre College of Engineering was awarded a grant from the U.S. Environmental Protection Agency to investigate a group of chemicals known as per- and polyfluoroalkyl substances, or PFAS.
Decades past have seen the restriction of insecticides, such as the banning of DDT –a chemical commonly found in various types of pest control – following the publication of Rachel Caron’s book Silent Spring. Now, we face a different issue: biosolids recovered from sewage and used as fertilizer.
Following a lawsuit filed against the EPA by the Public Employees for Environmental Responsibility (PEER) on behalf of farmers in Johnson County, all eyes are on PFAS: a group of synthetic substances known as “forever chemicals” due to their long-lasting nature.
Matthew Siebecker is a professor of environmental soil chemistry at Texas Tech University. He said our soil is filled with microorganisms like fungi and bacteria that are too small to be seen by the human eye.
Over time, organic contaminants can be broken down by these microorganisms.
“But then there's some contaminants that are just extremely recalcitrant and the microbes are not able to use them as a food source,” he said. “Which is, you know, what we see with the PFAS. They just persist for extremely long amounts of time, because they're highly resistant to degradation.”
Without organisms that are able to break down contaminants, the chemicals can sit in the soil making them readily available to plant life, and eventually, us.
Laura Dumais is staff counselor at PEER, which is currently working with two separate farmers outside of Dallas Fort-Worth. Following the spread of illness and loss of cattle, the families brought their concerns to the county.
“There was a huge dump of sewage sludge biosolids on a neighboring property and shortly thereafter all havoc broke loose like their the fish in their ponds all died, their cows started getting sick, birds were dying, everything was going wrong,” she said.
Soil samples taken by an environmental crimes investigator found unsettling levels of PFAS on the farms. The group of synthetic chemicals are commonly found in fire fighting foams used at airports or industry plants. Without being in close proximity to either and surrounded by farmland, investigators were able to narrow their search.
The alleged culprit: a fertilizer from Synagro Technologies comprised of biosolids.
According to the EPA website, dumping sewage sludge in the ocean was banned in 1988, leaving the question: how do we dispose of biosolids now?
“They said, ‘We could either burn it, we could landfill it, but let's make it an option to spread it on the land as fertilizer.’ And then they put this provision in the Clean Water Act that said, ‘Okay, EPA has to make sure it's safe,’” she said.
The loss of crop, cattle, and land is happening to farmers across the country, which Dumais said has led to questions of , “why was I told this is safe for my soil and why is this allowed?”
Dumais explained: “These folks are very brave. A lot of farmers in this situation just don't want anyone to know they want to continue selling their products because, you know, obviously it affects their whole livelihood, but they didn't want to sell the products they knew would be dangerous to their, you know, their neighbors.”
EPA has set a limit of 4 parts per trillion as a limitation for drinking water, the equivalent of one drop in 5 Olympic-size swimming pools.
According to PEER staff, one bite of a cow’s liver from the Johnson country farms contains 37,000 parts per trillion of PFAS.
With such a small amount permitted for water, soil chemists like Siebecker question what a safe amount of PFAS is for the soil, if there is one.
Dumais said that despite the Clean Water Act passing in 1972, the required biannual review was not started until the late 2000’s, meaning more than three decades passed potentially without recognizing and regulating new contaminants. She says that while the EPA continues to award grants for further information about each substance, this ignores the data that it already has.
“This is like the whole gist of our lawsuit. Like EPA has put up these huge hurdles for itself because it is afraid of being sued by industry,” Dumais said. “But this is not with the statute requires, I mean, the statute requires action, not perfection.”
Although further research needs to be done, there are ways to improve the quality of the soil and minimize contaminants.
“Everyone can make a difference in the soil that's around them, whether it's in your backyard, or whether you manage a large plot of land,” Siebecker said.
Siebecker said one way to improve soil health is by boosting organic matter.
With temperatures on the decline, one way you can incorporate organic matter into your own yard is by leaving the leaves.
According to the USDA, the leaves provide food for microorganisms, further increasing organic matter and reintroducing nutrients that help plants to grow stronger. Not only does it make for a great fertilizer, the leaves reduce soil erosion, giving a boost of help to the environment.
The EPA requested that the lawsuit be dismissed in early September, but litigation continues from PEER and the farmers in Johnson County.