COHP replies

The recommendations in the HealthLink BC files have been developed based on BC and Canadian evidence and data indicating safe and at-risk human body mercury levels and consumption levels. The BC Centre for Disease Control (BCCDC) and the Ministry of Health Services (MOHS) agree with Health Canada’s review of mercury toxicity levels and the guidelines limiting mercury to below 1.0 ppm and 0.5 ppm for most fish and shellfish species sold in Canada. But because BC fish consumption patterns are unique in Canada and there is regional variation in mercury levels in the fish available to consumers across Canada, Health Canada’s fish consumption guidelines regarding mercury risk do not apply well in the BC context. For British Columbians, information on local patterns of fish consumption, local levels of mercury in different fish species, and local risk factors for elevated blood mercury were carefully considered.

In addition, the BCCDC and the MOHS categorized the mercury level in different fish species into low (<0.1 ppm), moderate (between 0.1 ppm and 0.5 ppm), and high (>0.5 ppm) making them easier to understand. Health Canada has one regulatory cut point of 0.5 ppm of mercury and has recom­mended consumption limits for fresh and frozen tuna and canned albacore. Health Canada states that canned albacore tuna has higher mercury levels than other types of canned tuna and therefore does not recommend limits for consuming other types of tuna. The BCCDC and MOHS support grouping all canned tuna, including albacore, into the moderate category.

The types of recommendations can be confusing, especially between the different canned tuna, and fresh and frozen. Since the BCCDC and the MOHS have focused on local fish and local risk factors, their recommendations may be more appropriate.

—Shefali Raja, BSc, RD
Nutrition Committee, Council on Health Promotion