Is the Susquehanna River So Dirty It’s Giving Fish Cancer?

Cancer in fish is rare. When officials find it happening, alarm bells go off. If you’re anywhere near Pennsylvania’s Susquehanna River, perhaps you can hear those bells beginning to ring? Some experts do.

In the fall of 2014, an angler fishing on the Susquehanna River caught a smallmouth bass with a big problem. It had a huge, rather grotesque growth on its mouth.

The angler turned in the fish to the Pennsylvania Fish and Boat Commission (PFBC). After testing, the PFBC confirmed this month that the growth was a malignant tumor. That fish had cancer. The U.S. Fish and Wildlife Service and the Aquatic Animal Health Laboratory at Michigan State University concurred the finding.

This is that unlucky fish:

Photo credit: John Arway, Pennsylvania Fish and Boat Commission

Photo credit: John Arway, Pennsylvania Fish and Boat Commission

According to the PFBC, this is the only documented case of a cancerous tumor being found on a smallmouth bass in the entire state. However, some experts have worried about the health of the Susquehanna River for at least a decade.

“As we continue to study the river, we find young-of-year and now adult bass with sores, lesions and more recently a cancerous tumor, all of which continue to negatively impact population levels and recreational fishing,” said PFBC Executive Director John Arway in a press release. “The weight of evidence continues to build a case that we need to take some action on behalf of the fish.”

Oddly, the Pennsylvania Department of Environmental Protection (DEP) and Department of Health are not reacting to the PFBC’s concerns as expeditiously as hoped.

“There is no evidence that carcinomas in fish present any health hazard to humans,” said Dr. Karen Murphy, acting Secretary of the Pennsylvania Department of Health. “However, people should avoid consuming fish that have visible signs of sores and lesions.”

Well, yes. Eating anything sporting lesions and sores is generally inadvisable, right? One continues to wonder about the environment that caused those abnormalities, though.

PFBC wants the DEP to add the Susquehanna River to Pennsylvania’s bi-annual list of impaired waterways. That would be the first step to getting it on the Environmental Protection Agency’s (EPA) official list of impaired waters. PFBC has been asking the state for this designation since 2012.

Causes of impairment, according to the EPA, include include chemical contaminants, physical conditions, and biological contaminants. The PFBC believes the problems with the fish ought to enable the state to determine the river is “ecologically impaired.”


The Susquehanna River

“The impairment designation is critical because it starts a timeline for developing a restoration plan,” Arway said. “We’ve known the river has been sick since 2005, when we first started seeing lesions on the smallmouth. Now we have more evidence to further the case for impairment.”

In 2012, the EPA did recognize that the Susquehanna can no longer be considered “unimpaired.” It noted:

The final report includes a change in the designation for a nearly 100-mile section of the main stem of the Susquehanna River from “unimpaired” for aquatic life and recreational uses, to having insufficient water quality data to make an impairment determination. That change from the draft to the final report reflects comments submitted to PADEP from EPA and others, as well as ongoing efforts to identify the cause of health impacts to the Susquehanna’s smallmouth bass population.

EPA acknowledged there’s an issue to be addressed, but still believes it does “not have sufficient data at this time to scientifically support listed the main stem of the Susquehanna as impaired,” according to NPR.

Smallmouth bass with cancerous lesions, taken from the Susquehanna River.  Photo credit: R. Bane/Pennsylvania Fish and Boat Commission

Smallmouth bass with cancerous lesions, taken from the Susquehanna River. Photo credit: R. Bane/Pennsylvania Fish and Boat Commission

“If we do not act to address the water quality issues in the Susquehanna River, Pennsylvania risks losing what is left of what was once considered a world-class smallmouth bass fishery,” Arway noted. “DEP is expected to release its 2016 list of impaired waters in late fall. We are urging them once again to follow the science and add the Susquehanna River to the list.”

People catch and eat these fish. Animals do too. What’s in the Susequehanna River that’s been causing sores and lesions for the last decade, and now perhaps cancerous tumors too? It’s worth noting that EPA’s listing of Impaired Waters by State shows that Pennsylvania has far more such troubled waterways than any other state.

The problem — and the negative impact on fish — seem undeniable. Something is wrong in that river. The Susquehanna’s problem needs attention now.

Do you want to help PFBC convince the Pennsylvania DEP to designate the Susquehanna River as impaired in 2016? If so, please sign this petition. Tell John Quigley, Acting Secretary of the DEP, how you feel about this important matter.

Photo credit: Thinkstock


Mark Donner
Mark Donner2 years ago

Leave it to the mentally impaired paid off "officials" to declare a polluted river unimpaired.

Siyus Copetallus
Siyus Copetallus3 years ago

Thank you for sharing

Oceane Ingram
Oceane Ingram3 years ago

Thanks for sharing!

Julia Cabrera-Woscek

I concur with Barbara S. Time will come that we will have nothing safer to eat from the wild because we have the environment so contaminated.

Vicky P.
Vicky P3 years ago

wow :/

Nikki Davey
Nikki Davey3 years ago


Paulinha Russell
Paulinha Russell3 years ago


David Anderson
David Anderson3 years ago

And to think that 40 years ago we thought it was a big deal for a river to catch on fire--and we never imagined fish with cancer. Unfortunately, any effort to prevent and correct this will likely end up like previous efforts including the establishment of the EPA itself. We will find those who are not really part of the problem micromanaged to death while the usual suspects continue with their malfeasance unabated. For example, I can receive tons of grief and micromanagement if a puddle on my farm holds water for more than a few days a year (regulated wetland and all) but we still have what we have in the rivers and nothing ever seems to get done about it.

The J.
Vikram S3 years ago

thanks for sharing

Hussein Khalil
Hussein Khalil3 years ago