PCBs in your fish dinner?
Polychlorinated biphenyls (PCB) were used for decades in industry and to make electrical equipment like transformers and capacitors.[i] They are slow to break down and hard to destroy. PCB are known carcinogens and have been linked to adverse reproductive, immune, nervous and endocrine effects, among others.[ii] Trace levels are found in air and water throughout the world. Each of us has PCB in our bodies, mainly from our diet. So do the fish.
The maximum permitted concentration of PCB in fish in Canada is 2 ppm; this is currently being re-evaluated by Health Canada. [iii] [iv] The US standard is slightly tougher – they apply the same number, but only to the edible parts of fish and shellfish.[v] The estimated average Canadian eats less than 0.5 mcg/day of PCBs, but those who eat a lot of fish may get more. [vi]
Health Canada thinks we shouldn’t worry. It monitors contaminants in food, including PCBs[vii] and has sometimes checked retail fish for contaminants, such as PCBs.[viii] They conclude that most commercial fish contain very low levels of PCBs (parts per billion), and they do not restrict consumption of fish purchased in supermarkets. [ix] [x] But Slow Death by Rubber Duck showed that even low levels of contaminants in food (mercury in tuna) can rapidly drive up human body burdens. Sports fish can be much more contaminated. And what about fish oil capsules?
Jackie Campbell and Dianne Saxe
[i] Health Canada. PCBs. 2001 November; updated 2005 October. At http://www.hc-sc.gc.ca/hl-vs/alt_formats/pacrb-dgapcr/pdf/iyh-vsv/environ/pcb-bpc-eng.pdf
[ii] US Environmental Protection Agency. Health effects of PCBs. Last updated August 8, 2008. At http://www.epa.gov/epawaste/hazard/tsd/pcbs/pubs/effects.htm
[iii] Canadian Food Inspection Agency. Appendix 3
Canadian Guidelines for Chemical Contaminants and Toxins in Fish and Fish Products (last modified September 9 2009). At http://www.inspection.gc.ca/english/fssa/fispoi/man/samnem/app3e.shtml
[iv] Personal e-communication with Health Canada – April 12, 2010
[v] US Food and Drug Administration – Food – Guidance, compliance and regulatory information – Guidance documents – Appendix 5 FDA & EPA Safety Levels in Regulations and Guidance. 2001 June. At http://www.fda.gov/Food/GuidanceComplianceRegulatoryInformation/GuidanceDocuments/Seafood/FishandFisheriesProductsHazardsandControlsGuide/ucm120108.htm
[vi] Health Canada. PCBs. 2001 November; updated 2005 October. At http://www.hc-sc.gc.ca/hl-vs/alt_formats/pacrb-dgapcr/pdf/iyh-vsv/environ/pcb-bpc-eng.pdf
[viii] Health Canada – Fish and Seafood Survey – 2002. At http://www.hc-sc.gc.ca/fn-an/securit/chem-chim/environ/mercur/servey_sondage-eng.php
[ix] Health Canada. Canadian standards”maximum limits” for various chemical contaminants in foods. Last modified July 9 2007. At http://www.hc-sc.gc.ca/fn-an/securit/chem-chim/contaminants-guidelines-directives-eng.php#guidelines
[x] Health Canada. PCBs. 2001 November; updated 2005 October. At http://www.hc-sc.gc.ca/hl-vs/alt_formats/pacrb-dgapcr/pdf/iyh-vsv/environ/pcb-bpc-eng.pdf