Mercury in Fish

HealthLinkBC File Number: 
Last Updated: 
December 2018

Mercury in Fish

Fish provides many nutrients including protein, vitamin D, iodine and iron. Many fish are also good sources of omega-3 fats, which are good for your brain and heart. These fats also support brain and eye development and benefit pregnant and breastfeeding women, babies and children.

Eating Well with Canada's Food Guide (CFG) recommends eating at least 2 servings of fish each week. While there are health benefits of eating fish regularly, it is important to know that mercury is present in varying amounts in different types of fish. In large amounts, mercury can be harmful to your health.

In general, the more popular fish are relatively low in mercury, so most Canadians don’t need to be concerned if their intake is too high. The following fish can be eaten several times a week as part of a varied and balanced diet:

  • Fresh, canned or frozen salmon, sardines, herring, trout, char, smelt or eulachon and mackerel (good sources of omega-3 fats)
  • Fresh or frozen sole, cod, pollock, halibut
  • Canned light tuna including skipjack, yellowfin, tongol
  • Fresh, canned or frozen B.C. or Canadian albacore tuna*

Why limit high mercury fish?

Mercury can have harmful effects on the nervous system, including the brain. Babies and children are at most risk from exposure to high levels of mercury. Health Canada provides specific guidelines on choosing and eating fish for babies, children and pregnant and breastfeeding women.

Which fishes have high levels of mercury?

Fish with higher levels of mercury include:

  • Tuna** (fresh or frozen)
  • Shark
  • Marlin
  • Swordfish
  • Escolar
  • Orange roughy

Cleaning, preparing or cooking will not remove or reduce mercury in fish.

What is the serving limit Health Canada recommends for me and my family?

Fresh or frozen tuna**, shark, marlin, swordfish, escolar and orange roughy:

Age Serving Limit
Children 6 to 12 months 40 grams (1 ¼ ounces) per month
Children 1 to 4 years 75 grams (2 ½ ounces) per month
Children 5 to 11 years 125 grams (4 ounces) per month
Women of childbearing age, including pregnant and breastfeeding women 150 grams (5 ounces) per month
Men 12 years and older, and women after childbearing years 150 grams (5 ounces) per week

*Canadian North Pacific albacore tuna (fresh, frozen and canned) has been tested for mercury by the Canadian Food Inspection Agency and is considered safe to eat. The mercury level in these fish is lower than other albacore tunas. To find Canadian albacore tuna, look for the statement “Product of Canada” on the label.

**Note: Fresh or frozen BC or Canadian albacore tuna has no serving limits.

Canned albacore tuna from countries other than Canada*:

Age Serving Limit
Children 6 to 12 months 40 grams (1 ¼ ounces) per week
Children 1 to 4 years 75 grams (2 ½ ounces) per week
Children 5 to 11 years 150 grams (5 ounces) per week
Women of childbearing age, including pregnant and breastfeeding women 300 grams (10 ounces) per week
Men 12 years and older, and women after childbearing years No limit

*Note: Canned albacore tuna labelled with “Product of Canada” has no serving limits.

Why is there mercury in fish?

There are natural sources of mercury found in the environment, but human activity such as mining, burning waste and hydroelectric dams have increased the amount of mercury in soil and water. Fish absorb this mercury, and your body absorbs mercury when you eat the fish.

Can I eat fish caught by family and friends?

Yes. The risk of mercury in lakes and streams in British Columbia is considered to be low in most areas. Testing is done when there is known contamination, a risk of contamination and where there are natural mercury deposits.

As of 2015, 3 lakes in B.C. have mercury advisories. These advisories are for lake trout and bull trout in Jack of Clubs, Pinchi and Williston Lakes.

For More Information

For more information, visit the following:

For information on freshwater fishing regulations in B.C., visit or call toll free 1 877 952-7277.

For more nutrition information, call 8-1-1 to speak with a registered dietitian.

Is it an emergency?

If you or someone in your care has chest pains, difficulty breathing, or severe bleeding, it could be a life-threatening emergency. Call 9-1-1 or the local emergency number immediately.
If you are concerned about a possible poisoning or exposure to a toxic substance, call Poison Control now at 1-800-567-8911.

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