Something's Fishy: Many locally caught fish are not safe to eat

Summer fish fries are awaited throughout the year and are among Missourians’ favorite summer meals. Not only delicious, fish boasts many health benefits. It’s high in protein and low in saturated fat. It also contains omega-3 fatty acids, which are good for the heart and brain.

The American Heart Association recommends eating fish two or three times a week to help reduce heart disease. Scientific evidence suggests that fish’s fatty acids help keep brain-cell membranes healthy and may allay depression and Alzheimer’s disease.

This is great news, but it’s also important to know about the health risks of eating fish, whether it’s bought at the store or caught from your local fishing hole. For Missourians who cook their catch, every year the Missouri Department of Health and Senior Services issues a fish advisory providing guidelines for eating locally caught fish. (For the 2005 advisory, visit

According to Todd Blanc, an environmental specialist, the advisory is designed to provide Missourians with information to protect their health. It explains contaminants in Missouri’s fish and describes fish to avoid eating and where they can be found. But he said it also contains information to help people enjoy fish, such as how to prepare them to get rid of chemical contaminants that build up in fish fat. Trimming away excess fat in the dorsal, lateral and belly while cleaning the fish has been proven to reduce the levels of some types of chemicals in fish, but will not reduce the level of metals such as lead or mercury.

“This information is not meant to scare everybody,” Blanc said. “Fish are an important food source, but we want to inform certain populations who are sensitive to the contaminants in fish.” Blanc identified those contaminants as PCBs, chlordane, lead and mercury. They sound frightening, but informing yourself about the facts of each will help you avoid exposure. So catch up on this latest health information and enjoy your next catch.

PCBs and chlordane

Polychlorinated biphenyls and chlordane are contaminants present in the Missouri and Mississippi rivers that build up in the flesh and eggs of the shovelnose sturgeon. The MDHSS advises Missourians not to eat this fish.

PCBs, once used for commercial and industrial materials, and chlordane, which was used as a pesticide, are chemicals that have been banned from use for more than a decade. The production of PCBs was banned in 1977, and chlordane was banned in 1988. PCBs were found to cause cancer and a variety of adverse health effects on the immune, reproductive, endocrine and nervous systems, while chlordane causes damage to the nervous system and liver. Despite the bans, PCBs and chlordane still exist in the environment, such as in rivers and streams as a result of past wastewater discharges.

The good news is that levels of PCBs and chlordane in Missouri waterways are declining, and the same trend is being seen in fish that live in those waters. In 2001, the MDHSS removed its limited-consumption advisory for catfish, carp, buffalo, drum, suckers and paddlefish.


The MDHSS also has issued an advisory against eating sunfish, carp, redhorse and other suckers found in the Big River in Jefferson and St. Francois counties and along six miles of the Flat River in St. Francois County from Highway B to its conjunction with the Big River. It also advises against eating sunfish from Big Creek near Glover in Iron County. These fish contain levels of lead that may cause a variety of health problems in almost every system of the body. Low-level lead poisoning can impair neurobehavioral development and can damage the kidneys, the central nervous system and reproductive system.

Lead pollution in Missouri waterways is the result of lead-mine waste piles. State officials speculate that the Big Creek near Glover was contaminated by nearby lead smelters. Catfish was once on the do-not-eat list, but sampling since 1992 has shown that this species no longer contains dangerous levels of lead. However, the advisory against eating fish from the Big River and Flat River will remain indefinitely. According to Blanc, samplings have shown that the lead levels in those waterways have stayed consistent from year to year.


Although a naturally occurring element in the environment, mercury is a developmental toxicant in humans and can cause a variety of adverse health effects, including neurological damage, especially in the developing nervous system. Its presence is increased in the environment through emissions from industrial sources such as trash incinerators and coal-fired power plants.

“In Missouri, mercury is the cause for the biggest concern,” Blanc said. “It bioaccumulates in the environment and magnifies up the food chain. We advise pregnant women, women who plan to become pregnant and children under the age of 12 to avoid eating largemouth bass larger than 12 inches.”

Bioaccumulation occurs when micro-scopic plants and animals absorb mercury in its organic and highly toxic form, methylmercury, and then these organisms are consumed by small fish, which are then consumed by larger fish. Largemouth bass are likely to have the highest levels of mercury since they are, in most parts of Missouri, the largest predatory fish. The MDHSS advises against eating largemouth bass larger than 12 inches because mercury stores up in the animals’ bodies over time, whereas smaller fish will have lower levels of mercury. This advisory is in effect for the entire state of Missouri.

Due to national advisories by the U.S. Environmental Protection Agency, the Missouri Departments of Conservation and Natural Resources are conducting their own analysis of predatory fish in Missouri. Based on the information the state collects, it will determine whether additional advisories should be issued for other predatory fish in Missouri besides largemouth bass.

Blanc recommended that Missourians also review the EPA guidelines for eating purchased fish, which provide information about mercury levels in saltwater fish and how often it is safe for sensitive populations to eat fish (up to 8 ounces a week for locally caught fish). For more information, visit

A Missouri fisherman’s take on eating locally caught fish

Lewis Morgan, president of St. Louis Bassbusters, said he would have no reservations about eating fish from one of Missouri’s lake reservoirs, though all of his fishing is catch-and-release. But he said there is cause for concern about eating fish from rivers, including the Missouri and the Mississippi.

Despite this, he believes that most fishermen of both Missouri lakes and rivers are unconcerned about the potential health risk of eating locally caught fish. “Ask someone about a fish consumption advisory, and he wouldn’t know what you were talking about,” he said.

Morgan is optimistic and even proud of the quality of Missouri water and said the state is doing an excellent job to improve it and keep it clean. He also believes Missouri is a one of the best states in the nation for fishing for food as well as fishing for sport and recreation.

“Sport fishing is a high-dollar revenue source in Missouri,” he said. “This state protects its waters ferociously.”