Mercury Levels in Canned Tuna: Understanding and Managing Exposure

The consumption of canned tuna is a common practice worldwide due to its convenience, affordability, and nutritional benefits. However, the mercury content in different types of canned tuna can vary significantly. Understanding and managing this exposure is crucial for both health and safety.

Types of Tuna and Mercury Levels

Mercury levels in tuna can vary depending on the type and size of the fish. Generally, larger and older fish accumulate more mercury. Typical mercury levels for different types of tuna are as follows:

Albacore Tuna (White Tuna): This type of tuna often has higher mercury levels, averaging around 0.3 to 0.6 parts per million (ppm). Some samples can reach up to 1.0 ppm or more. Skipjack Tuna (Light Tuna): This type of tuna typically has lower mercury levels, averaging around 0.1 to 0.3 ppm. Chunk Light Tuna: Often made from skipjack, this variety usually contains lower mercury levels compared to albacore.

The FDA recommends limiting the consumption of albacore tuna for pregnant women, nursing mothers, and young children due to its higher mercury content. Most adults can consume canned tuna in moderation but should check local guidelines if they are concerned about mercury exposure.

Specific Mercury Levels in Canned Tuna

For an average 5-ounce serving:

1 can of light tuna: Contains 18.11 micrograms of mercury. 1 can of albacore tuna: Contains 49.53 micrograms of mercury. Tuna steak or tuna sushi: Can contain up to 97.49 micrograms of mercury.

A distinction should be made between the two main types of canned tuna: chunk light and solid or chunk white albacore. Canned white tuna, which is albacore, has mercury levels almost three times higher than the smaller skipjack tuna used in most canned light tuna products.

Guidelines for Consumption

Consumption guidelines for different age groups are provided by health experts:

Children under six: Can eat up to one 3-ounce portion of albacore tuna per month. Older children and adults can safely eat it once a week. Adults including pregnant women: Can safely eat up to three 6-ounce portions of albacore tuna per month.

Light tuna, considered a safer choice, contains 0.12 parts per million (ppm) of mercury. Guidelines are:

Children under six: Can eat up to three 3-ounce portions per month. Older children and adults: Can safely eat it up to once a week.

Alternative Options: Canned Salmon

A better alternative to canned tuna is canned salmon, which is lower in contaminants and high in heart-healthy omega-3 fatty acids. Sockeye or pink salmon from Alaska are recommended due to their low mercury levels and sustainable practices. This type of canned salmon, similar in price to canned tuna, makes for a healthier and more environmentally friendly choice.

In conclusion, while mercury levels in canned tuna can vary, understanding these levels and following recommended guidelines is key to safe consumption. Choosing alternative options such as canned salmon provides a nutritious and safer dietary choice for consumers.