Marine Harvest Canada, along with all other MH Business Units worldwide, perform product testing for heavy metals, antioxidants, PCBs, flame retardants, chemical contaminants and triarylmethane dyes (such as Malachite Green and Crystal Violet). This testing program began in 2002 as a way to assure customers that there were no concerns with regard to the PCB levels and mercury levels found in our fish.
“What we are doing is due diligence”, said Food Safety Manager Jean Veale, adding that the company began routinely testing for PCBs before it became the more widespread concern it is currently.
PCBs, also known as polychlorinated biphenyls, are a class of organic compounds that were used industrially in transformers, coolants, sealants, and paints until their production was banned in the 1970s. Research by international health organizations has determined that PCBs are potentially cancer-causing.
Most but not all countries where Marine Harvest operates have set acceptable levels for heavy metals and PCBs with regard to human health risks. The limits are highly variable between countries and are generally set at a level that is 10 to 100 times lower than what would be considered “safe” for human consumption.
For example, Belgium has the world’s most strict regulations regarding acceptable PCB levels, at 75 ppb (parts per billion) for the seven compounds that indicate the presence of PCBs. China’s regulation is 200 ppb total, and Canada’s is 2,000 ppb.
Jean commented that all Marine Harvest companies, including Canada, are well under the Belgium’s threshold.
A recent published study found that PCBs in Canadian farmed salmon are the same or lower than the levels in wild salmon. (ref) This is because Canadian fish feed recipes specify greater replacement of fish meal with alternative proteins.
Testing for mercury levels is also done. Again, acceptable levels vary with China and Chile being the most strict in the world – with a maximum of.3 parts per million allowed. Canada has the second most stringent level, with .5 parts per million. Marine Harvest’s mercury levels are .05 parts per million – one tenth of the lowest allowable level.
“There are no issues with mercury (in our fish)”, added Veale.
All product testing is done four times annually by the same lab in Europe, using a 10 fish composite sample. “Composite” means that portions of all 10 fish are tested together. The samples are chosen at random although MHC ensures that both feed companies Marine Harvest Canada uses are always represented.
Regular testing allows us to be proactive and increase the probability of catching any potential issues early, commented Jean. For example, flame retardant levels were briefly included in the tests, however, when these proved not to be at levels of concern, they were discontinued.
“We’re always asking (the labs to test) for lower levels of detection”, Jean said.
The importance of being prepared with accurate data for customers is reinforced by Sales Director Ken Taylor.
“We want to provide useful and accurate information when customers request it,” said Ken, adding that questions regarding any heavy metal levels are “pretty rare” amongst Marine Harvest’s customers. “But we do need to be ready in case something hits the media so customers are given timely information, Ken concluded.
ref: Friesen, E. N.; Ikonomou, M. G.; Higgs, D. A.; Pee Ang, K.; Dubeta, C.; Use of Terrestrial Based Lipids in Aquaculture Feeds and the Effects on Flesh Organohalogen and Fatty Acid Concentrations in Farmed Atlantic Salmon. Environ. Sci. Technol. 2008, 42, 3519–3523
By Gina Forsyth