Malachite Green - Questions and Answers

Consumer Questions

Q. What is Malachite Green?

Malachite green (MG) is an antifungal agent approved for use in aquarium fish. It is not approved for use in fish intended for human consumption. MG has been used in certain countries for the treatment of external fungal and parasitic infections on fish eggs, fish and shellfish and is an effective fungicide, especially as a general fish hatchery disinfectant. MG is also used as an industrial dye in some manufacturing applications, including pulp and paper and textiles.

Q. Is the use of malachite green permitted in Canada?

MG is not approved for use in food-producing animals in Canada.

The Government of Canada advised against the use of MG in food fish in 1992. This includes use during the entire lifecycle of the fish, from the hatchery to the farm. MG is approved in Canada for use in the treatment of aquarium fish. It is used in a number of manufacturing applications, including pulp and paper and textiles.

Q. Is eating fish that contains trace levels of malachite green harmful?

Scientific evidence indicates that leucomalachite green, a metabolite of malachite green, may be a genotoxic carcinogen which persists in fish tissues long after malachite green can no longer be detected.

Health Canada has, however, conducted a thorough scientific health risk assessment and has determined that the potential risk to human from eating fish with levels of MG and or LMG residues at 1 ppb or lower is remote, even if fish with these levels are consumed every day, over a lifetime.

Q. What is Health Canada's advice to consumers regarding the consumption of fish containing trace amounts of malachite green?

All fish are an excellent source of high-quality protein and are low in saturated fat, which make them a healthy food choice. The probability of serious adverse health consequences from the daily consumption of fish containing trace amounts of MG/LMG is remote.

Consumers should continue to follow a balanced diet in accordance with Health Canada's Food Guide to Healthy Eating and follow any consumer advisories that may be issued relating to food by Health Canada, the Canadian Food Inspection Agency and Provincial or Territorial Agencies.

Q. If malachite green is a potential genotoxic carcinogen, why is it being permitted in food at any level?

Protecting the health of Canadians is Health Canada's primary concern. Deliberate use of malachite green in food producing animals is not permitted. This is not changing.

In regards to unavoidable exposure to contaminants, Health Canada takes the position that levels of contaminants should be minimized as much as possible, according to the "ALARA" approach (as low as reasonably achievable). Health Canada, the CFIA, and Fisheries and Oceans Canada will continue work on generating more scientific evidence through monitoring and testing, and to evaluate gathered data, with the goal of minimizing exposure even further.

Q. Why not maintain zero tolerance for the presence of malachite green while the government determines its prevalence in the environment?

Health Canada's zero-tolerance policy does remain in place for deliberative use. While it is unclear to what extent malachite green is present in the environment, data collected by the Canadian Food Inspection Agency (CFIA) since 2003 indicates that, in certain cases, the trace detection of MG/LMG residues in fish products are unlikely to be the result of intentional use. Given the sensitivity of some laboratories' testing procedures, a zero-tolerance policy is not achievable or realistic if a substance is present at background levels in the environment.

Canada's interim approach is a reasonable and achievable way of minimizing public exposure to risks associated with the presence of MG/LMG at trace levels. It maintains Health Canada's policy for zero-tolerance for deliberate use of malachite green in food-fish. This also acknowledges the remoteness of health risks associated with the consumption of trace amounts of this substance, and the importance of fish as a dietary source for Canadians. The approach allows for safe, nutritious fish products to be allowed on the Canadian market.

Q. Why is this an interim measure?

The Government of Canada and its provincial/territorial regulatory partners are putting in place an interim approach to deal with the presence of MG/LMG in fish as further investigation into the possible sources of the contamination is required. Over the next year, an interdepartmental working group comprised of Health Canada, the CFIA, and Fisheries and Oceans Canada will continue work on generating more scientific evidence through monitoring and testing, and to evaluate gathered data, with the ultimate goal of minimizing exposure even further.

Q. Do other countries have stricter action levels for the presence of malachite green?

Canada's interim action level is more conservative than action levels set in other countries, for example, the EU uses 2 ppb as an action level and Japan uses 5 ppb.

Q. What is the significance of Health Canada's interim limit of quantification (ILOQ) of .5 ppb?

Not all laboratories currently testing for MG and LMG in Canada can detect MG/LMG in fish at equally low levels. Therefore, Health Canada is setting an interim Limit of Quantification (ILOQ) requiring all laboratories to test to a performance level of .5 ppb. This is a scientifically valid, achievable level that allows test results to be confirmed in all Canadian laboratories testing for MG and LMG residues.

CFIA's Regulatory Approach

Q. What will be done with fish products found to contain MG or LMG at levels above 1 ppb?

Domestic and imported fish found to contain MG/LMG above 1 ppb will not be allowed for sale in Canada.

Q. What action will the CFIA take on products when detections are below .5 ppb?

When MG or LMG is detected in fish products below .5 ppb, the CFIA will not take regulatory action. The Agency will, however, gather all laboratory test results as part of the government's collection of data on environmental levels of MG/LMG.

Q. What will happen to products in which MG/LMG is detected between .5 ppb and 1 ppb?

For detections of MG/LMG between .5 ppb and 1 ppb, if an investigation determines MG was used intentionally, this fish will not be allowed to be sold in Canad

Q. Who will conduct investigations to determine intentional use?

Depending on the nature and origin of the product found to contain MG/LMG at a level between .5 ppb and 1 ppb, the responsible authority (provincial/territorial or CFIA) will conduct the investigation.

Q. Can the CFIA investigate intentional use in imported products?

Not directly. For imported product results with levels between .5 and 1 ppb, the importer will have the option of conducting an investigation and providing evidence that MG has not been deliberately used during the fish production life-cycle. The CFIA will take action on the product depending on the results of the investigation.

Q. Will product be detained during the investigation?

In all cases (domestic and imported), products found to contain MG/LMG at a range of detection between .5 ppb and 1 ppb will be detained or will remain under detection until an investigation determines whether MG was intentionally used during fish production.

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