While this makes fish one of the most sought after ingredients in the seafood industry, it has also become one of the protein sources many health organizations are monitoring meticulously because of the risks of contaminants.

Many of their concerns involve food poisoning, which often comes as a result of pathogenic organisms, including Salmonella.

Salmonella is a rod-shaped, gram-negative bacilli that can lead to foodborne illnesses and serious infections. It is a member of the Enterobacteriaceae family of bacteria and is facultatively anaerobic, which means it can grow either with or without oxygen.

Some may think that diarrhea — a primary symptom of many foodborne illnesses such as salmonellosis is a minor health issue — but the World Health Organization describes it as the second leading cause of death among children who are younger than five years old.

Salmonella in fish: It comes with the territory
Aquatic environments and their shorelines are considered to be major reservoirs for Salmonella. Hence, fishery products have been regarded as major sources of pathogens that originate from fish. There are three categories of pathogenic contamination that are often associated with fishery products and fish.

The first is indigenous bacteria, which refers to the type of bacteria that exists as part of the natural microflora of fish. The second, enteric bacteria or non-indigenous bacteria, occurs as a result of fecal contamination. The third is bacteria that is introduced during processing, storage, transportation or preparation for consumption. Salmonella falls under the second group.

The increased run off of organic matter into freshwater bodies such as ponds during rainfall events can also contaminate an aquaculture system with various bacteria and other pathogens. Animal waste, fertilizers, contaminated feed, unsanitary water and other elements of farming are also contributing factors to the prevalence of Salmonella.

Some research, however, shows that fish — except river fish — are not considered a natural habitat of Salmonella. In fact, Benjamin Chapman, a specialist on food safety and associate professor at North Carolina State University, argues that Salmonella in fish can occur as a result of improper handling during preparation or processing.

People who handle the food, in processing facilities or restaurants, probably don’t wash their hands properly every time they should. It is also possible that other meats, which are in the same processing facilities — such as beef or poultry — can cross contaminate fish and fishery products.

How to prevent Salmonella poisoning
As with any other types of meat, the risk of foodborne illnesses is much higher in fish that are raw or undercooked as compared to those that are cooked to the proper temperature to kill pathogens.

The Centers for Disease Control and Prevention recommends using a food thermometer to make sure food is cooked to a safe internal temperature. For fin fish, the CDC’s recommended internal temperature is 145 degrees. Make sure to let the meat rest for about 3 minutes before eating or carving.

Refrigeration is another treatment approach. Freezing fish for 15 hours at minus 35 degrees C, or for a week at minus 20 degrees C is considered an effective way to kill some parasites. But freezing does not kill all pathogens, including listeria monocytogenes, hepatitis A or Vibrio vulnificus.

It is also important that people who catch their own fish carefully select fishing spots that are less prone to pollutants, such as bodies of water that are not contaminated with animal manure.

Food safety measures for people who eat raw fish
Although many studies describe the potential hazards of eating raw meat and fish, including the risk of Salmonella infection, many people still believe in the health benefits of eating raw proteins. Other research suggesting it is beneficial is not uncommon.

Frying fish, for instance, can decrease the level of omega-3 fatty acids such as docosahexaenoic acid (DHA) as well as eicosapentaenoic acid (EPA) which are both healthy and essential for the development of the brain. The same fatty acids also reduce the risk of heart-related illnesses, and some studies found they can even lower the risks of depression.

For these reasons, it is undeniable that raw fish dishes have gained popularity across the globe. Examples include Sushi and Sashimi from Japanese cuisine. Soused herring, a marinated raw herring, is common in the Netherlands. In Latin America, the marinated seafood dish ceviche, which usually consists of raw fish cured in lime juice or lemon, is popular.

For reducing the risks of contaminants and poisoning from raw fish, experts suggest eating only fish which have been frozen. Buy from reputable shops or suppliers, and buy refrigerated fish.

Always inspect your fish by making a visual check, and make sure that it smells fresh. Never keep fresh fish for too long and never leave it out for too long. Always work in a clean kitchen, and wash your hands frequently.

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The American Heart Association suggests fish consumption at least two times each week, and each serving must be 3.5 ounces cooked which is equivalent to three-fourths of a cup of flaked fish.

Meanwhile, the North Carolina Division of Public Health states that consumers must avoid eating fishes that contain high levels of mercury. This health organization also listed some fishes that have low amounts of the said contaminant. Here are five of the fishes that pose less health risk.

No. 1 Salmon
An evaluation of contaminant consumption risk regarding various POPs or persistent organic pollutants, including polychlorinated biphenyls, dioxins, and dioxin-like compounds referred to as DLCs, has found that Southeast Alaskan sockeye, coho, chinook, pink, and chum salmon, as well as Kodiak pink, coho, and chum salmon, are wild-caught salmon types that belong to the lowest risk category.

Aquabounty Technologies has also introduced Atlantic salmon which are genetically-engineered to increase its production. The U.S. Food & Drug Administration, after rigorous scientific review, has identified that genetically-modified salmon is as safe-to-eat as the conventional ones. This is based on comprehensive analysis of the scientific evidence, and 20 years of research, testing, development, evaluations, and regulations.

Meanwhile, the wild vs. farmed salmon controversy has become a complicated issue that draws attention on media, online and various scientific publications which all tend to provide contradictory reports. However, the Washington State Department of Health verified that both contain low amounts of mercury, PCBs, and other contaminants.

No. 2 Tilapia
Along with various aquatic animals including shrimp and salmon, tilapia is one of the fishes that the American Pregnancy Association recommends for pregnant women because of its low mercury content. Eating 8 to 12 ounces of these fish is also advisable according to the FDA.

Oceana, the largest international organization for ocean advocacy and conservation, has supported this argument in their analysis where tilapia had an average mercury level amounting to 0.08ppm which is below the FDA’s 1.0ppm “action level,” qualifying tilapia as a low-mercury fish. “Low mercury” tilapia, therefore, is still considered a good option.

FDA’s previous findings even suggest a lower mercury level of 0.01ppm from the eight samples that they analyzed. In 2009, a study about halogenated contaminants of certain fish types and species including trout, salmon, shrimp, pangasius, and tilapia were conducted. Results suggest that contaminant concentrations in farmed tilapia were lower compared to those in wild fish.

No. 3 Canned Light Tuna
Early this year, U.S. Environmental Protection Agency (EPA) and FDA had issued advice regarding fish consumption to serve as a guide for women who are pregnant or may become pregnant including parents of young children and breastfeeding mothers as well as young children themselves.

The said advice suggests that canned light tuna belongs to “Best Choices” which means that eating 2 to 3 servings based on four ounces serving size per week is advisable and may pose less to no risk. Meanwhile, yellow tuna and Albacore, sometimes called white tuna, belong to the “good choices” category. The ideal serving is once a week while bigeye tuna is in the “choices to avoid” category and should not be consumed.

Albacore is a large type of tuna that lives long and usually has higher mercury content compared to canned light tuna which is a small tuna species and is mostly skipjack.

No. 4 Cod
Coldwater fish like cod can be very beneficial for people who are suffering from diabetic heart disease and atherosclerosis. Many previous studies have also revealed that cod is a great source of blood-thinning omega-3 and is also an excellent source of vitamin B6 and B12 which are both essential in keeping the homocysteine levels low.

Homocysteine is known to be a dangerous molecule that can directly damage blood vessels. High homocysteine also contributes to an increased risk of stroke and heart attack.

According to a Harvard study, baked or broiled, but not fried, cod may also lessen the potential for the development of atrial fibrillation which is considered the most common form of heart arrhythmia, a condition that mostly affects elders.

The 12-year study reviewed 4,815 people who were 65 years and older. Findings revealed that increased blood levels of omega-3 fatty acids correlated with eating broiled or baked fish one to four times a week.

No. 5 Flounder
This fish is a low-calorie, low-fat fish which is also a source of selenium, vitamin B12, vitamin D, and omega-3 fatty acids. It contains small amounts of mercury. Windowpane flounder is a pollution-sensitive fish.

In general, the presence of healthy flatfishes is an indication of clean water and sediment. Furthermore, flounder is considered an excellent source of protein. The U.S. Department of Agriculture National Nutrient Database claims that each 3-ounce portion of grilled flounder which is cooked using dry heat has about 2 grams of fat, 13 grams of protein, and no carbohydrates.

The protein of Flounders is a high-quality, complete protein because it has all the essential amino acids. The human body can make some amino acids but can not synthesize essential amino acids. Hence, it needs to take these organic compounds from dietary sources.

Takeaways from the list
The more pressing problem lies on the consumer’s lack of awareness about the chemicals that certain aquatic animals may contain. Depending on what type of consumer you are, it is always important to limit certain fish species from certain bodies of water.

EPA also suggests that you take extra care especially if you are a frequent consumer of fish, elderly, pregnant or nursing, or a young child as these groups are at a greater risk from fish contamination.

If you know how to fish and consume the ones you catch, it is best to read advisories regarding the mercury content, POPs, dioxins and other possible contaminants that your target fish may have.

About the author: Rebecca Lily is a country girl who grew up to have a “way too boring desk job” in New York City. She launched a blog, thatfishing.com, to feed her passions, fishing, writing and cooking. Lily got her first fishing rod when she was 9 and caught her first trout the same year.

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