It’s 40 degrees on a Wednesday morning in Eufaula and White Oak Creek is quiet except for the puttering of a diesel generator and a faint wee-oh, wee-oh sound reminiscent of a European ambulance siren.
That high-pitched sound means the two squid-like collections of wires dangling into the water are pulsing out electricity out into the water, around the dock posts and sunken trees where the fish like to hide.
The jolt will stun the fish for a few minutes, long enough for Alabama environmental authorities to collect them, analyze the results and let us know whether they’re safe to eat.
The fish are sent to an ADEM lab for processing. Lab techs will fillet the fish, using one fillet from each fish for analysis and freezing the other, in case it’s needed for additional testing. ADEM will test each fish for several contaminants including mercury, polychlorinated biphenyls (PCBs), and PFOS.
The results from that sampling will go to the Department of Public Health, where toxicologist Dr. John Guarisco will analyze the results and publish the advisories.
Mercury is the driver of most advisories statewide. If the fish show even moderately elevated levels of mercury, Guarisco can recommend people limit their consumption to one or two meals per month. If the concentrations are higher, the state may recommend that no one eat any fish from that waterway.
In 2019, Alabama recommends not eating any species of fish caught in the following 12 locations: Baker’s Creek at Wheeler Reservoir (PFOS); Chickasaw Creek in Mobile County (mercury); Cold Creek swamp in Mobile County (mercury); Cowpen Creek in Baldwin County (mercury); the Mobile River at Cold Creek (mercury); Polecat Creek in Baldwin County (mercury); three different sites on Choccolocco Creek (PCBs, mercury); the Perdido River near U.S. 90 bridge (mercury); Persimmon Creek west of Georgiana (mercury); and the Sepulga River in Escambia County (mercury).
From fish to advisories
The catfish are harder to catch. Ambush predators like bass can reliably be found around structures under the water, often where people have sunk old Christmas trees or other debris to boost their own fishing fortunes.
Catfish could be anywhere, and the electricity only penetrates about 15 feet down into the water column.
On the water in Eufaula, Matt Thomas, a senior environmental scientist for ADEM, is manning the apparatus from the front of the department’s water quality monitoring boat. Net in hand, and foot on the kill-switch that keeps the current flowing into the water, Thomas scans the water’s surface, waiting for incapacitated fish to float to the top.
He’ll have only a few minutes to survey the floaters and pick out the ones he needs before they recover and swim off.
Len has earplugs in, sitting next to the generator, so they communicate with hand signals. Back it up a little. There’s a bass floating under this dock that might work.
ADEM needs six bottom-feeders (in this case, catfish) and six predators (largemouth bass) from each location for the survey.
The ADEM fish collectors try to find average-sized fish, the kind recreational anglers are most likely to catch. They try to get six of the same species to make an equal comparison. ADEM catches fish in the fall because contaminants that build up in the fatty tissue are more likely to be elevated after a summer of heavy feeding.
Why it matters
Eating fish can be a healthy, low-fat option, but many fresh and saltwater fish absorb toxins from the water. Some of those toxins accumulate up the food chain and can cause health problems for people who eat too many contaminated fish.
Since 1970, the state of Alabama has set out to monitor the water quality and keep tabs on what contaminants are getting into our fish. Over the decades, those efforts have morphed into a collaborative effort among the Alabama Department of Environmental Management, the Alabama Department of Public Health, the Alabama Department of Conservation and Natural Resources and the Tennessee Valley Authority.
Each year, these agencies collaborate on a document – released in June or July – naming all the water bodies where fish have been documented showing high levels of contamination.
The three contaminants that drive fish advisories in Alabama are mercury, PCBs and PFAS compounds. PCBs and PFAS compounds are man-made chemicals that are primarily found near industrial facilities where those chemicals were manufactured or used heavily.
The last catfish
Len and Thomas navigate their boat around the shallow mud flats where White Oak Creek flows into the larger reservoir, Lake Eufaula. The boat gets stuck a couple of times and both men use their six-foot nets to push off from the bottom.
The catfish are slower to surface after being stunned, and Len circles back where a catfish had surfaced briefly but swum off before Thomas could net it. Finally, after about two and a half hours on the water, the survey is complete.
The fish are put on ice back at the boat launch – specially treated ice to avoid contamination – and the ADEM team loads up to move on to the next site. They’ll visit one more today and two more tomorrow on this mid-week sampling trip of Lake Eufaula.
What’s in the fish?
Of the main contaminants of concern, mercury is found nearly everywhere, while PCBs are found mostly in the Coosa River near Anniston and PFAS in the Tennessee River near Decatur.
Manufacture of PCBs was banned in 1976, but the chemicals do not break down in the environment and can still be found in concerning concentrations in places like Snow Creek, Choccolocco Creek, Lake Logan Martin and Lay Lake. PCBs have been shown to cause cancer in laboratory animals and are associated with effects on the immune system, reproductive system, nervous system, endocrine system and other health effects.
PFAS compounds are also extremely slow to biodegrade and can accumulate over time. Those substances have been associated with negative health impacts when present in drinking water over a long period of time.
Mercury occurs naturally in the environment, but most contamination observed in the environment now comes from human emissions such as burning coal.
The U.S. Environmental Protection Agency first began regulating mercury emissions from coal-fired power plants in 2011, through measures which the Trump administration has proposed rolling back.
The mercury in the air is disbursed widely through the atmosphere and ends up in waters, where bacteria convert the substance into methylmercury, which is a form that can be absorbed by fish.
Guarisco said the places where fish contamination is the highest tend to be areas where these bacteria thrive rather than the places near large mercury emitters such as coal-fired power plants. The contamination accumulates up the food chain from small fish to larger fish to humans. Larger, older fish tend to accumulate the most, as the mercury builds up over time. Large predator fish such as freshwater bass or tuna, shark and swordfish in the Gulf tend to be high in mercury.
Mercury is a neurotoxin and can have negative effects on unborn children, impacting development and cognition. In adults, exposure to mercury can cause kidney damage, nervous system damage or heart disease, though Guarisco said such acute side effects are rare.
Logistical limits
The consumption advisories can provide more information for people who regularly eat fish, but there are limitations to how effective they are.
ADEM environmental scientists sample about 45 sites every year, but 132 sites have some type of consumption advisory. There are 87 locations where state health officials recommend people not eat any of certain types of fish.
Ramsey Archibald | rarchibald@al.com
State health officials recommend not eating certain species of fish caught in these 87 locations in Alabama.
ADEM has divided the freshwater rivers of Alabama into five zones for sampling, focusing its monitoring efforts on a different zone every year, along with a handful of coastal sites. Additional sites outside of that year’s focus area are chosen based on past advisories and other criteria, but many sites will only be checked once every five years. Those with active advisories will be sampled at least every three years.
This year, ADEM crews sampled only one spot outside of the focus area, on the Black Warrior River northwest of Birmingham.
Scott Hughes, chief of ADEM’s field operations branch, said the Department coordinates with the ADPH, ADCNR to decide which sites to sample outside of that year’s area of concentration.
Although ADEM (or its predecessor agencies) has sampled fish tissue for contaminants since 1970, Hughes said there is no dedicated source of funding for the program.
“We've got these valuable water resources and we know that people like to get out enjoy those resources,” Hughes said. “We’ve got a lot of people that love to fish, and a lot of people that consume fish as part of their diet, so it's something that we've just always taken upon ourselves as a service that we wanted to provide for the people of Alabama.
“We found ways to support the efforts within ADEM and other agencies.”
Fisherman's Right to Know
Justinn Overton, executive director of Coosa Riverkeeper, said the state doesn’t do enough to publicize the advisories.
In 2014, Coosa Riverkeeper surveyed fishermen at the Neely-Henry and Logan-Martin Dams on the Coosa River about the advisories and found that only 40 percent of those surveyed were aware of the advisories.
“Sending out a press release once a year is not effectively communicating with the public,” Overton said.
Overton, who said she grew up eating fish out of the Coosa River reservoirs, has worked for years with the Riverkeeper group to publicize the advisories and talk with the fishermen who regularly pull their dinners from the waters. The group, along with the Alabama Rivers Alliance, created a hotline and web site where people can get more information about the advisories, including a read-aloud listing of
“Fishing is an intergenerational thing,” Overton said. “It is it is a pastime that grandfathers and granddaughters and families have shared on the Coosa River for a very long time. That's not something that we're looking to change.
"We're just looking to make the data about fish tissue and contaminants in it more readily available so people can make informed decisions.”
ADEM has made strides to improve communication efforts, by posting signs at several of the collection sites with QR codes that people can scan to direct them to the full list of advisories.
Overton said that clearer messaging that doesn’t require a someone to scan a QR code with a smartphone would be more effective.
Coosa Riverkeeper has also been critical of the way the advisory thresholds are calculated. Some advisories recommend eating only “one meal” per month, in which a “meal” portion is defined as six ounces of cooked fish. Many typical portion sizes are larger than 6 oz, Overton said.
Overton said Coosa Riverkeeper is working with local legislators on a potential piece of legislation called a fisherman’s right to know act to codify improvements to the program and potentially include a dedicated source of funding for the effort.
“This could be a win for everybody, and why not have it be about fishing, which is a common denominator for so many people,” Overton said.
What you can do
Guarisco said his number one recommendation is to read the advisories before fishing if you plan to eat your catch and contact ADPH at 1-800-338-8374 if you have questions.
If you do plan to eat fish from the rivers where an advisory is in effect, cooking and cleaning it properly is helpful. Some toxins like PCBs are stored in the fatty tissue, so allowing the drippings to fall away while cooking can reduce the concentrations. Deep-frying, however, traps these tissues in the fish, and re-using cooking oil can increase contamination levels.
Since mercury accumulates in the muscle tissue, there is no effective way to cook a fish to minimize its mercury content.
The U.S. Food and Drug Administration recommends that pregnant women and young children consume fish as part of a healthy diet, but avoid high-mercury species like shark, swordfish, tilefish or marlin.
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Are Alabama fish safe to eat? Here’s how the state decides - AL.com
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