There are many benefits to including fish (including shellfish) in a balanced diet for people of all ages. Fish are high in protein, low in fat, and contain healthy oils called omega-3 fatty acids which are important during fetal development and which help prevent heart disease in adults. For more information on eating fish, visit the U.S. Food and Drug Administration’s page on fish recommendations: www.FDA.gov/fishadvice.
Additionally, fishing can be a rewarding hobby that brings people closer to nature, provides a source of natural food, and can even help with wildlife conservation. For more information on fishing in Ohio, visit the Ohio Department of Natural Resource’s Fishing Basics page: http://wildlife.ohiodnr.gov/fishing/fishing-basics.
The levels of contaminants found in Ohio fish are not known to cause immediate sickness in humans.
Over time, contaminants can build up in a person’s body. It may take months or years of regularly eating contaminated fish to build up amounts of contaminants that are a health concern. One week of eating too much fish or shellfish is not likely to cause noticeable health problems.
If you eat too much fish or shellfish in one week, the Ohio Department of Health advises that you reduce the amount you eat during the following week. For example, the recommendation is that adults should eat no more than 4 ounces of Ohio sport fish per week. If you eat 8 ounces of Ohio sport fish in one week, then you should eat none the following week. If you eat 12 ounces of Ohio sport fish in one week, then you should eat none for the following two weeks, and so on.
All lakes that have fish with higher levels of contaminants are listed in the Ohio Sport Fish Consumption Advisory booklet. If you don't see the public lake where you fish in the booklet, then you may safely consume the fish you catch from the lake according to the general advisory.
You cannot tell if a fish advisory is needed by whether a body of water looks or smells dirty.
Because the contaminant levels that Ohio EPA looks for when it samples fish are so small, you cannot see, smell, or taste them in the water or fish. A body of water and its fish can look clean but actually be contaminated and require an advisory.
On the other hand, a body of water can look dirty for reasons other than contaminants like PCBs and mercury. Bacteria and algae (microscopic plants) can cause the water to look discolored, murky, or muddy, or cause a bad odor. Recent heavy rains can stir up sediment and cause water to look cloudy or brown. Even if this is the case, a fish advisory may not be needed.
Choose smaller fish (within the legal size limit). Smaller fish within a species tend to have fewer contaminants than older, larger fish.
Choose leaner fish. Fish that are higher in fat (channel catfish and carp, for example) will likely have more fat where PCBs and other chemicals build up. Yellow perch, sunfish, and crappies are examples of lean fish.
Trim and cook your fish properly to reduce your risk. When preparing whole fish, trim off the skin and fat to reduce contaminants. Cook and eat only the fillet. Baking, broiling, or grilling the fish can cook off PCBs, and these methods won’t add extra unhealthy fats as with frying.
Graphic courtesy of the Ohio Environmental Protection Agency
A fish consumption advisory is a recommendation to help people eating Ohio-caught fish make educated choices about: where to fish, what types of fish to eat, how to determine the amount and frequency of fish you consume, and how to prepare fish for cooking.
While most Ohio sport fish are safe to eat, low levels of harmful chemicals like polychlorinated biphenyls (PCBs) and mercury have been found in some fish from certain Ohio waters. To protect the health of anyone who eats Ohio-caught fish, the Ohio Department of Health offers an advisory for how often these fish can be safely eaten. A consumption advisory is a recommendation meant to protect people eating Ohio-caught fish and should not be viewed as law or regulation.
Fish consumption advisories are designed to protect the most at-risk (vulnerable) members of the population, especially infants, children, and women who are pregnant, breastfeeding, or planning to become pregnant. This will also ensure that people who are less at-risk will be protected.
Not all fish are contaminated. Contaminants that are found in some Ohio fish include polychlorinated biphenyls (PCBs), pesticides, and metals like lead and methyl mercury. The contaminants responsible for most advisories are PCBs and methyl mercury.
PCBs are man-made oils that were once used to make copying paper and electrical equipment. PCBs break down very slowly in the environment and build up in fish through the food chain.
Mercury is a metal that occurs in nature. Natural sources of mercury include volcanoes and forest fires, but it can also enter the environment through human activities like coal-burning power plants. Methyl mercury is a mercury compound that builds up in fish through the food chain.
The levels of methyl mercury and PCBs found in Ohio fish are not known to cause immediate sickness in humans.
Over time, methyl mercury and PCBs can build up in a person’s body. It may take months or years of regularly eating contaminated fish to build up amounts of contaminants that are a health concern. It takes up to six years for the body to get rid of PCBs, and up to one year to get rid of mercury after a person stops eating contaminated fish.
Health problems that may result from the contaminants in fish include birth defects (including developmental and physical deficits) in newborns of mothers who eat highly contaminated fish for many years before becoming pregnant. Mercury has been known to cause heart problems in older adults and can cause problems with the brain and nerves.
Contaminants in fish can be harmful to people of all ages, but fetuses, infants, and children through age 15 are most at-risk because their bodies and organs are still developing. They are less able to deal with toxic substances than an adult.
Women who plan to become pregnant, women who are pregnant and nursing mothers should be aware of fish contaminants as it may affect their babies. Women of childbearing age and pregnant or nursing mothers should consult with their doctors on how to make fish a part of their diet.
Fish taken from rivers, streams, lakes, and reservoirs throughout Ohio often have small amounts of chemical contaminants. Limiting the number of sport fish meals eaten ensures that the contaminants do not build up in your body to levels that may be harmful. Data collected from lakes and rivers in Ohio show a statewide advisory of one meal per week of most Ohio sport fish is protective.
For an adult, Ohio recommends that an adult should eat 4 to 6 ounces of cooked fish per meal. Serving sizes for children should be smaller and adjusted for their age and size. Ohio recommends that a child should eat 2 to 3 ounces of cooked fish per meal.
Based on mercury contamination, the U.S. Food and Drug Administration (FDA) recommends that one meal (also called a serving) should be 4 ounces for adults. For children 7 years old and younger, the FDA advises that serving sizes for children should be smaller and adjusted for their age and size, about 2 ounces. For more information, visit the FDA Advice About Eating Fish webpage.
The Ohio Department of Health is not recommending that you stop eating sport fish EXCEPT where there is a Do Not Eat advisory. Fish with low levels of contaminants are safe to eat, provided the trimming, cooking and meal frequency advice is followed.
Although the Ohio Sport Fish Advisory is mainly focused on sport fish caught in Ohio waters, the Ohio Department of Health encourages adding a wide variety of fish to your diet and understands that even people who fish will often add store- or restaurant-bought fish to their diet. Most kinds of fish on the market, including fish from restaurants and grocery stores, are safe to eat and low in contaminants. For more information on which fish to eat, visit the U.S. Food and Drug Administration’s page on fish recommendations: Advice about Eating Fish.