Anglers who enjoy catching their dinner should do so just once a week, or perhaps less frequently depending on the species of the fish and the location where it's caught.
The Ohio Environmental Protection Agency's updated fish consumption advisory for 2013 relaxed regulations for some areas but added restrictions for others.
Bodies of water that saw lower mercury levels resulted in more relaxed advisories. They include the Ashtabula River, Deer Creek, Deer Creek Lake, Lake Erie, Pike Lake, Ross Lake and Stonelick Lake.
Only the Great Miami River, Lake Erie and the Scioto River had more restrictive advisories after this year's study, according to a news release by the Ohio EPA.
The regulations regarding fish advisories from local rivers, streams and lakes remained constant because no research was done on the local area this year.
"The EPA generally looks at different rivers and lakes on a rotation of about once every five years or so," said Linda Fee Oros, spokesperson for the EPA. "It really just depends on what they have time for as to how many can get done every year."
At a glance
Advisory restrictions for Local Rivers:
Restrictions for the Little Muskingum River (located from Hill's Covered Bridge to the mouth of the Ohio River in Washington County).
Freshwater Drum, once a month, due to mercury and PCBs.
Spotted Bass, once a month, due to mercury.
Restrictions for the Muskingum River (located from the Zanesville Dam to the mouth of the Ohio River including Morgan,Muskingum, Washington counties).
Smallmouth buffalo 24 inches and over, once every two months, due to Polychlorinated Biphenyls (PCBs).
Channel catfish, common carp, smallmouth buffalo under 24 inches, and all white bass, once a month, due to PCBs.
Flathead catfish 24 inches and over, saugeye once a month due to mercury and PCBs.
Freshwater drum, once a month due to mercury.
Restrictions for the Ohio River (located from the Pennsylvania Border to the Belleville Lock, including Athens, Belmont, Columbiana, Jefferson, Meigs, Monroe, Washington Counties)
Channel catfish 18 inches and over, DO NOT EAT due to PCBs.
Channel catfish under 18 inches, common carp and white bass once every two months due to PCBs.
Black Crappie, Flathead Catfish, Freshwater Drum 14 inches and over, largemouth bass, sauger, saugeye, smallmouth bass, smallmouth buffalo, spotted bass, striped bass, all suckers, walleye and white crappie; once a month due to PCBs.
Source: Environmental Protection Agency's website (epa.ohio.gov
Oros said that generally, advisories remain pretty constant from year to year.
"Some bodies of water get slightly better and some get slightly worse in the time between advisories," said Oros. "Nothing we found this year was a drastic change from what we have seen in the past from those areas."
It has been several years since the Ohio EPA has had a chance to test the local bodies of water.
The last time that the Ohio River was sampled was in 2003, the Muskingum River was in 2006, and the Little Muskingum River was tested in 2009, this according to the EPA website.
All three bodies of water still have the previous restrictions regarding the consumption of certain species currently in place.
These restrictions are due to potentially harmful chemicals that can build up in fish.
Polychlorinated biphenyls (PCBs) are highly toxic industrial compounds that accumulate in the bottom of rivers, lakes and streams that can build up in the fatty tissues of fish. There are over 200 different PCB compounds and high concentrations of the compound pose serious health risks to anyone if ingested, this according to the Environmental Defense Fund website.
Mercury can be released into the environment through natural occurrences such as volcanic activity, but most are due to coal burning, gold mining and manufacturing plants. Mercury can be consumed by plankton and then works its way up the food chain to fish, according to the Stony Brook University website. High amounts of some mercury can cause gastrointestinal problems, according to the U.S. EPA.
All of the species of fish restricted in the area are because of potentially high mercury or PCB levels.
In the Little Muskingum, located from Hill's Covered Bridge to the mouth of the Ohio River in Washington County, a one meal a month advisory is in place for spotted bass due to mercury. Residents may also enjoy a meal per month of freshwater drum in the Little Muskingum, because of both mercury and polychlorinated biphenyls (PCBs).
In the Muskingum River, from the Zanesville Dam to the mouth of the Ohio River, there is a meal every 2 months advisory on smallmouth buffalo over 24 inches due to PCBs.
Channel catfish, common carp, all white bass and smallmouth buffalo under 24 inches, are under a meal a month advisory due to PCBs in the Muskingum River. A one meal per month advisory is also in affect for flathead catfish over 24 inches and saugeye due to mercury and PCBs.
Freshwater drum may be eaten only once a month from the Muskingum River due to elevated mercury levels in the species.
In the Ohio River, located from the Pennsylvania border to the Belleville Lock south of Parkersburg, no channel catfish over 18 inches should ever be ingested because of PCBs. All channel catfish under 18 inches, white bass and common carp, can be eaten by residents only one meal every two months due to PCBs.
Due to the presence of PCBs, any freshwater drum 14 inches and over, black crappie, white crappie, smallmouth buffalo, flathead catfish, sauger, saugeye, smallmouth bass, largemouth bass, walleye, spotted bass, stripped bass, and suckers in the Ohio River may only be consumed once per month.
"It's very important that everyone is aware of any consumption advisories that exist for water sources located near them," said Mike Greenlee, fish management supervisor with the Ohio Department of Natural Resources Division of Wildlife.
Most fish that are caught in the wild are generally very safe, and are a healthy choice to include in a diet, according to Greenlee.
Some fish in Ohio waters, especially smaller species, actually have a lower chance of contaminants compared to larger sport fish.
"Crappie, yellow perch, bluegill and other species of sunfish tend to have lower amounts of contaminants," said Greenlee. "The Ohio Department of Health and the EPA state that in most cases, two meals of these species may be consumed per week, rather than only one."
Greenlee stated that preparation was another great way to limit the amount of contaminants found in wild fish.
"When filleting the fish it's important to remove the skin and trim as much of the fat as possible," he said. "An area to pay extra close attention to is the belly area where there is a large portion of fat next to the muscle."
Anglers aren't going to be able to tell what bodies of water are contaminated based on their appearance so these advisories are the only way they will know what's safe, according to Greenlee.
"This isn't something you can visually look for, these are compounds that can only be found by testing in a lab," he said. "That's why it's extremely important people rely on the results of these advisories so they can eat what they catch safely."