2013-14 Perchlorate in selected foods

Targeted surveys are used by the Canadian Food Inspection Agency (CFIA) to focus its surveillance activities on areas of highest risk. The information gained from these surveys provides both support for the prioritization of the Agency's activities to areas of greater concern and scientific evidence to address areas of lesser concern. Originally started under the Food Safety Action Plan (FSAP), targeted surveys have been incorporated into the CFIA's regular surveillance activities as a valuable tool for generating essential information on certain hazards in foods, identifying/characterizing new and emerging hazards, informing trend analysis, prompting/refining human health risk assessments, assessing compliance with Canadian regulations, highlighting potential contamination issues, and promoting compliance.

The main objectives of this survey were to:

• generate baseline surveillance data on the levels of perchlorate in fresh vegetables, processed fruit and vegetable products, dairy products, infant formula, grain products, and assorted foods available on the Canadian retail market; and
• compare the perchlorate levels in these results to other Canadian and international data on perchlorate, where possible.

Perchlorate is a chemical that occurs naturally in the environment (e.g., in some nitrate and potash deposits or formed in the atmosphere). It is also an environmental contaminant resulting from industrial processing of rocket propellants, explosives, road flares, fireworks, and automotive airbags. Since perchlorate readily dissolves in water, it can be taken up and accumulated by plants and may also be transferred to animals through the consumption of perchlorate-contaminated feed or water.

Human exposure to perchlorate occurs primarily through ingestion of food and water. At sufficiently high doses, perchlorate can interfere with the uptake of iodide by the thyroid gland which is required to produce hormones essential for metabolism and growth.

In the current survey, a total of 477 samples of fresh vegetables, processed fruit and vegetable products, dairy products, infant formula, grain products, and assorted foods were collected from Canadian retail stores between April 2013 and March 2014 and analyzed for perchlorate. Two hundred and five of the 477 samples (43%) did not contain a detectable level of perchlorate. Overall, 71% of fresh vegetables, 40% of processed fruit/vegetable products, 80% of dairy products, 54% of infant formula, 30% of grain products, and 61% of assorted foods contained detectable levels of perchlorate ranging from 2 parts per billion (ppb) to 3300 ppb (detected in an arugula sample). The highest average perchlorate levels were found in fresh vegetables (130 ppb) and processed fruit/vegetable products (23 ppb), while the lowest average levels were found in grain products (5 ppb) and dairy products (6 ppb).

The occurrence and levels of perchlorate found in this survey were generally comparable with those reported in previous CFIA surveys as well data from the U.S. Food and Drug Administration (U.S. FDA), the European Food safety Authority (EFSA), and the scientific literature.

All data were shared with Health Canada's Bureau of Chemical Safety (BCS), including the arugula samples with the highest perchlorate levels (3300 ppb). The BCS determined that none of the perchlorate levels observed in this survey posed a human health concern, so no product recalls were warranted.

The CFIA will continue its surveillance activities and inform the Canadian public and stakeholders of its findings.