Mercury Under the Waves: a look at Mercury in Fish Ashley McElroy Walden University PUBH 6165-6 Hello, my name is Ashley McElroy and today I am focusing on the toxic effects of mercury and why fish advisories are so important. I will begin with a brief overview of what mercury is, where it’s found, and how we come into contact with it. Then I am going to move on to the importance of continuing, maintaining, and protecting the public from fish with high levels of mercury and current fish advisories.

What is Mercury? Is a heavy metal. Naturally occurring in the environment. Combines with carbon to make organic mercury compounds. Information obtained on March 17, 2009 from http://www.greenfacts.org/en/mercury/l-2/mercury-1.htm Information obtained on March 15, 2009 from http://www atsdr.cdc.gov/tfacts46.html#bookmark02 First, I want to take a quick moment to review what mercury is and where it comes from. Mercury is a naturally occurring element, that combines with carbon to form different organic compounds.

Mercury Continued Most common type of organic mercury is Methylmercury. Considered most toxic form of mercury. Methylmercury is found in many everyday foods. It is especially predominant in fish. Information obtained on March 15, 2009 from http://www.atsdr.cdc.gov/tfacts46.html#bookmark02 Although there are many forms that mercury can take, the most common type of mercury is organic mercury, which is known as methylmercury. Methylmercury can be found in many foods, however is most predominant in fish.

What is Methylmercury & Where is it Found? Methylmercury is formed in water and soil by small organisms.  Here it is eaten by plankton and krill. The plankton is eaten by fish.  Nearly all fish have trace levels of mercury. Fish that are larger in size or are older tend to have the highest levels of mercury. Some types of fish have higher levels of mercury than other types. Information obtained on March 23, 2009 from http://www.epa.gov/fishadvisories/advice/ Information obtained on March 15, 2009 from http://www.atsdr.cdc.gov/tfacts46.html#bookmark02 Methylmurcury is formed in the soil and water by small bacterial organisms, which is then eaten by fish that are living in the streams and waters contaminated by methylmercury plankton. Almost all fish have certain trace levels of mercury in them, however the older the fish or the larger a fish is, the higher levels of mercury can be found. It should also be known that all fish have different levels of mercury in them, some fish have higher mercury levels than others, we touch more on that shortly. So now that we know what methylmercury is………

Why Does this Matter? Methylmercury follows the food chain. Starting in fish and plankton. Which is consumed by humans. Leads to many health concerns. Information obtained on March 20, 2009 from http://www.ag.unr.edu/naes/Impact_Details.aspx?ImpactID=40 Why does any of this matter? Well, methylmercury follows the food chain, starting with fish or plankton and then working all the way up to humans. Humans ingest methylmercury by ingesting fish contaminated with methylmercury. Which leads to a series of health concerns. So the question is, what fish should we be aware of

Fish with High Levels of Mercury Shark Swordfish King Mackerel Tilefish Information obtained on March 19, 2009 from http://www.cfsan.fda.gov/~frf/sea-mehg.html It’s important to know what fish are safer than others. Some fish have higher mercury levels, like shark, swordfish, king mackerel, and tilefish.

Fish with Lower Levels of Mercury Salmon Sardines Tilapia Hake Haddock Complete Information Available at: http://www.cfsan.fda.gov/~frf/sea-mehg.html Information obtained on March 19, 2009 from http://www.cfsan.fda.gov/~frf/sea-mehg.html Examples of fish that have lower levels of mercury are: salmon, sardines, tilapia, hake, and haddock. For the complete list of fish and shellfish and the mercury levels that they contain, log onto the U.S. Department of Health and Human Services and the Environmental Protection Agency at http://www.cfsan.fda.gov/~frf/sea-mehg.html

What about Omega-3 Fatty Acids? Are Okay , if…….. Molecular Distillation Steam Deodorization Technologies U.S. Standards for Contaminants Information obtained on April 7, 2009 from http://www.edf.org/page.cfm?tagID=19376 A new question then arises, are fish oil pills okay to take? There has been a lot of controversy regarding fish oil pills. However, according to the environmental defense fund after a series of studies on different types of fish oil, they concluded that they are for the most part safe, but need to meet certain standards. Look for fish oil supplements that have been through the most stringent processing such as molecular distillation or steam deodorization, and show that they have met the U.S Standards for contaminants.

Who is at Risk? Everyone A fetus is most susceptible Factors that influence level of health risk Dose Age Duration Health Information obtained on April 9, 2009 from http://www.epa.gov/hg/effects.htm So now that we know what mercury is, how we come to ingesting mercury, and why this matters, moving ahead lets look at the risks and health problems due to mercury. Mercury affects everyone, however fetuses are the most susceptible to the poisoning effects of mercury. Factors such as how much mercury is ingested, how old a person is, over what period of time a person is exposed to mercury, and the overall health of the person exposed all play a vital role in how mercury will effect them.

Health Hazards of Ingesting Methylmercury Negative effects on brain Negative effects on nervous system Cognitive thinking impairment Information obtained on April 9, 2009 from http://www.epa.gov/hg/effects.htm There are many health hazards that can result from ingesting mercury, especially to a fetus, infants, and children. Serious negative side affects on the brain and nervous system can occur, effecting both growth and development. But also affecting cognitive things such as memory, thinking, fine motor skills, and visual development.

Hazards of Ingesting Methylmercury Vision problems Abnormal Sensations Coordination problems Speech Impairments Information obtained on April 9, 2009 from http://www.epa.gov/hg/effects.htm Other health problems that can arise from mercury poisoning are vision problems, abnormal sensations like tingling, coordination problems, and speech impairments. If you think you or someone that you know shows signs and symptoms of mercury poisoning seek medical attention immediately.

What can we do? Limit intake of fish to once a week; or once a month if pregnant. Stay away from fish with high levels of mercury. Eat a variety of fish with low levels of mercury. Limit fish intake to 12 ounces a week. Information obtained on April 5, 2009 from http://www.epa.gov/fishadvisories/advice/factsheet.html Here are some things to keep in mind when eating fish. The Environmental Protection Agency recommends that a person should limit their fish intake to once a week or no more than once a month if pregnant. Look out for fish that are on the list to have higher levels of mercury and when eating fish, eat a variety of fish with low mercury levels, not the same fish all the time. Try to keep your fish intake to 12 ounces, if you eat more, limit what you eat the next time you eat fish.

Importance of Fish Consumption Advisories Potential health hazards. Help the public choose Fish Guide Information obtained on April 9, 2009 from http://dnr.wi.gov/fish/consumption/ Advisories are essential to healthy living and to healthy eating choices for the public. Fish advisories inform the public of potential health hazards and what type of fish are safest to catch. But most importantly advisories provide a guide to the public of what fish are lower in contaminants and okay to consume. It is essential for the public to be aware of the levels of mercury in fish.

Fish Consumption Advisories in Oregon Emigrant Reservoir in Jackson County Portland Harbor Cottage Grove Reservoir in Lane County Dorena Reservoir in Lane County Information obtained on April 9, 2009 from http://www.oregon.gov/DHS/ph/envtox/fishadvisories.shtml Fishing is a very popular sport in Oregon, which is why fish advisories are essential to the health and safety of Oregonians. Some of the most recent fish advisories in Oregon include Emigrant Reservoir in Jackson County, where elevated levels of mercury where detected in Bass with mercury levels at .82 per ppm. In Portland Harbor elevated levels of of PCB’s were found in bass, carp, and catfish. Another advisory in Cottage Grove in Lane County found that mercury levels in bass, were on average 1.3 ppm. Lastly and advisory in Dorena Reservoir also in Lane County showed that mercury levels in Bass have risen since 1993 by .37ppm. Without these advisories, many people would have been susceptible to the health concerns of mercury.

Key Points to Walk Away With Methylmercury is an organic form of mercury, that is considered the most toxic. Methylmercury is found in a variety of fish. Mercury is extremely dangerous to a fetus. Consume fish that have low levels of mercury. Look for fish advisories in your area. Some key points to walk away with from this informative presentation are: Methylmercury is an organic form of mercury that is considered the most toxic. It can be found at certain levels in all types of fish. Methylmercury is extremely dangerous to a fetus, but can also have serious health affects to infants and young children. When eating fish limit your weekly intake to 12 ounces once a week and look for a variety of fish with low mercury levels. Most importantly always keep and eye out for fish advisories in your area, this can help you choose what type of fish to eat and what to avoid.

References: Agency for Toxic Substances and Disease Registry (1999). ToxFaqs for Mercury. Retrieved on March 15, 2009 from http://www.atsdr.cdc.gov/tfacts46.html#bookmark02 Environmental Defense Fund (2009). How Safe are Fish Oil Supplements? Retrieved on April 7, 2009 from http://www.edf.org/page.cfm?tagID=19376 Environmental Protection Agency (2009). Mercury. Retrieved on April 9, 2009 from http://www.epa.gov/hg/effects.htm#meth Environmental Protection Agency (2004). What You Need to Know About Mercury in Fish and Shellfish. Retrieved on March 23, 2009 from http://www.epa.gov/fishadvisories/advice/ Green Facts Digest (2004) Scientific Facts on Mercury. Retrieved on March 17, 2009 from http://www.greenfacts.org/en/mercury/l-2/mercury-1.htm Office of Research Facilities (2006). Mercury Health Hazards. Retrieved on April 7, 2009 from http://orf.od.nih.gov/Environmental+Protection/Mercury+Free/MercuryHealthHazards.htm

References Oregon Department of Human Services (2009). DHS Environmental Toxicology Program. Retrieved on April 9, 2009 from http://www.oregon.gov/DHS/ph/envtox/fishadvisories.shtml University of Nevada (2009). Assessment of Potential for Mercury Methylation in One of Reno Nevada’s Local Streams. Retrieved on March 20, 2009 from http://www.ag.unr.edu/naes/Impact_Details.aspx?ImpactID=40 U.S Department of Health and Human Services & Environmental Protection Agency (2006). Mercury Levels in Commercial Fish and Shellfish. Retrieved on March 17, 2009 from http://www.cfsan.fda.gov/~frf/sea-mehg.html Wisconsin Department of Natural Resources (2008). Fish Consumption Advisories. Retrieved on April 9, 2009 from http://dnr.wi.gov/fish/consumption