Furan, 2-methylfuran and 3-methylfuran in selected foods – April 1, 2021, to March 31, 2023

Targeted surveys are used by the CFIA to focus its surveillance activities on areas of highest health risk. The information gained from these surveys provides support for the allocation and prioritization of the agency's activities to areas of greater concern. Originally started as a project under the Food Safety Action Plan (FSAP), targeted surveys have been embedded in our regular surveillance activities since 2013. Targeted surveys are a valuable tool for generating information on certain hazards in foods, identifying and characterizing new and emerging hazards, informing trend analysis, prompting and refining health risk assessments, highlighting potential contamination issues, as well as assessing and promoting compliance with Canadian regulations.

Food safety is a shared responsibility. We work with federal, provincial, territorial and municipal governments and provide regulatory oversight of the food industry to promote safe handling of foods throughout the food production chain. The food industry and retail sectors in Canada are responsible for the food they produce and sell, while individual consumers are responsible for the safe handling of the food they have in their possession.

The main objectives of this targeted survey were to generate further baseline surveillance data on the level of furan, 2-methylfuran and 3-methylfuran in domestic and imported products on the Canadian retail market, and to compare the prevalence of furans in foods targeted in this survey with that of similar products in international surveys and to the scientific literature.

Furan may pose a health risk to consumers since the IARC has classified it as 'possibly carcinogenic to humans'^{Footnote 4}. Furan can sometimes form in foods that undergo heat treatments, particularly in foods that contain ascorbic acid, polyunsaturated fatty acids, amino acids and sugars^{Footnote 1, Footnote 2, Footnote 3}. In some foods, 2-methylfuran and 3-methylfuran can also form, which have a similar toxicity to furan^{Footnote 5}. Because thermal treatments are widely used for manufacturing shelf-stable food, it is important to establish data on the prevalence of furan, 2-methylfuran and 3-methylfuran in food available on the Canadian retail market.

MLs for furans have not yet been established, as the toxicity of furans in humans is not well known. The U.S. Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA) have studied furan levels in a variety of commodities^{Footnote 6, Footnote 7}, but limited data is available concerning 2- and 3-methylfuran levels. The objective of this survey was to establish further baseline surveillance data and to expand upon the data collected by other agencies.

A variety of domestic and imported baked goods (crispbread, crackers and croutons), infant and toddler food (purees and meals) and noodles (instant soup and instant pasta) were sampled from April 1 to March 31 over the 2021 and 2022 survey years. Samples of products were collected from local/regional retail locations in 6 major cities across Canada. These cities encompassed 4 Canadian geographical areas:

• Atlantic (Halifax)
• Quebec (Montreal)
• Ontario (Toronto and Ottawa)
• West (Vancouver and Calgary)

The number of samples collected from these cities was in proportion to the relative population of the respective areas. The shelf life, storage conditions, and the cost of the food on the open market were not considered in this survey.

Samples were analyzed by an ISO 17025 accredited CFIA food testing laboratory. The furans level reported per sample is the sum of the levels of furan, 2-methylfuran and 3-methylfuran, where detected. The results presented represent finished food products as sold and not as they would be consumed, whether the product sampled is considered an ingredient or requires preparation prior to consumption.

In the absence of established tolerances or standards for furans in foods, elevated levels in specific foods may be assessed by Health Canada on a case-by-case basis using the most current scientific data available.

Of the 748 samples tested, 644 (86%) had detected levels of furans. Table 1 shows that the detection rate of furans varied between product types. Among all product types included in this survey, the average concentration was highest in baked goods and lowest in noodles.

Most (58%) of the positive samples contained all 3 furan analogues. In 200 products furan and 2-methylfuran were both detected, 4 samples contained furan and 3-methylfuran, and 11 samples contained only 1 analogue (furan or 2-methylfuran). Furan had the highest average concentrations in all product types.

Baked goods had highest detection rate and the highest levels of furans reported in this survey. The highest level of furans (459 ppb) was reported in a sample of grain-free crispbread. Although most infant/toddler food samples tested were positive for furans, the levels observed were relatively low compared to other foods tested to date^{Footnote 8}. Within the infant/toddler food samples, fruit-based purees contained the lowest average levels of furans, whereas products containing meat or fish had the highest. Noodles also contained relatively low levels of furans.

For all product types, furan levels found in this survey were comparable to the levels reported in the scientific literature and previous targeted surveys^{Footnote 6, Footnote 7, Footnote 8, Footnote 9, Footnote 10, Footnote 11, Footnote 12, Footnote 13}. Table 3 only compares levels for furan for product on the Canadian market, as limited data is available concerning 2- and 3-methylfuran levels in foods.

The literature shows that 2-methylfuran and 3-methylfuran can form alongside furan from precursors found in foods, although limited data is available concerning specific precursors or reaction pathways^{Footnote 14, Footnote 15}. The variety of 2- and 3-methylfuran levels in foods sampled in this survey is possibly due to differences in ingredients and processing, which may favour the formation of different furan analogues.

Although there was limited data available for comparison of the survey results on furan in crispbread, crackers and croutons, the levels observed in this survey were within the range reported in literature^{Footnote 7, Footnote 10}. Large variability of furan levels within each brand of products and between different lots of the same product suggested, that in some cases the processing practices have larger effect on the furan levels than the ingredients.

The furan levels found in infant/toddler foods were within the range reported in the scientific literature and previous targeted surveys^{Footnote 8, Footnote 9, Footnote 11}. The classification of infant foods into savory products containing meat or fish and fruit and/or vegetable-based purees allowed to confirm the trend reported previously; which shows lowest amounts of furan in fruit and/or vegetable only recipes^{Footnote 8, Footnote 9, Footnote 11}.

There was limited data available for comparison of the survey results on furan in noodles, specifically in instant noodle-based soup. In this survey the results represent the entire product, including soup-base. When furan levels reported were compared to those from a study that reported levels for both noodles and soup-base and both values were considered, the results were comparable^{Footnote 12}. The results for plain instant noodles were also comparable to the levels reported in the scientific literature^{Footnote 13}.

Health Canada's Bureau of Chemical Safety determined the levels of furan, 2-methylfuran and 3-methylfuran in food observed in this survey are not expected to pose a concern to human health; therefore no follow-up actions were required.