Analysis of lead, arsenic, and cadmium concentrations in instant noodles within the Canadian market

Abstract

Background: High levels of lead (Pb), arsenic (As), and cadmium (Cd) in instant noodles have been reported in many countries, leading to temporary bans of several popular brands across the globe. There have been no studies analyzing the heavy metal contamination of instant noodles available in Canada to assess the risk for Canadians. As these contaminants are ubiquitous, their presence in food products is inevitable. A diet high in Pb, As, and Cd can cause permanent health conditions and death, as these metals are highly toxic even in small amounts and cannot be metabolized by the body. Methods: 30 packets of instant noodles were purchased from 6 different brands available in Walmart and T&T. Individual packs of noodles, and the accompanying dry seasoning packs, were ground using a blender and stored in sterile Ziplock bags. The samples were processed using an acid digest and then analyzed using ICP-MS/MS. Concentrations of lead, arsenic, and cadmium were measured for a comparison with FDA recommended levels, a cross comparison between wheat and rice noodles, and across all 6 brands. Results: The results show that the levels of Pb, As, and Cd found in instant noodles do not exceed the maximum allowable limits set forth by the FDA and EFSA. A significant difference between rice and wheat noodles is noted for As and Pb concentrations, where rice > wheat (p<0.05). A significant difference between brands is also noted for all three metals (p<0.05). Conclusion: Although the results did not find Pb, As, and Cd concentrations to exceed the recommended levels, the results of this study are inconclusive due to the low power of the analyses. It has been established that rice noodles contain overall higher levels of Pb and As than their wheat counterparts, and the levels vary significantly between different brands. The results indicate a wide window of variability of exposure for Canadians and the low power of the study indicates a larger need for further studies to confirm the findings.